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legendboy
02-20-2012, 03:12 PM
Figured I would post up some pictures of my retrofit project. Not going to post up huge amounts of detailed commentary, happy to answer questions however.

It started a couple months ago when I found it for sale somewhat locally, couple hours away.

Been wanting a cnc mill for a long time and this thing is exactly what I wanted.

Pic at its last home

http://www.telusplanet.net/public/shackner/R2E3/mill.JPG

Brought it too my work, took enough of the head apart to get it under my garage door. Grabbed a skid from my local machine tool dealer, added eye bolts and strapped it down.

http://www.telusplanet.net/public/shackner/R2E3/skid.JPG

I wussed out and hired riggers to move it

http://www.telusplanet.net/public/shackner/R2E3/move/IMG_2698.JPG

http://www.telusplanet.net/public/shackner/R2E3/move/IMG_2691.JPG

my neighbours think i am crazy

legendboy
02-20-2012, 03:12 PM
http://www.telusplanet.net/public/shackner/R2E3/move/IMG_2693.JPG

http://www.telusplanet.net/public/shackner/R2E3/move/IMG_2695.JPG

http://www.telusplanet.net/public/shackner/R2E3/move/IMG_2699.JPG

legendboy
02-20-2012, 03:20 PM
Started doing lots of reading on different controls and drives.

Ended up deciding on Granite VSD-XE drives and USBCNC from edingcnc.com

It took me a while to get the drives bench tuned properly but I had some help and finally got it figured out.

http://www.telusplanet.net/public/shackner/R2E3/retorfit/1.JPG

http://www.telusplanet.net/public/shackner/R2E3/retorfit/2.JPG

http://www.telusplanet.net/public/shackner/R2E3/retorfit/3.JPG

legendboy
02-20-2012, 03:21 PM
http://www.telusplanet.net/public/shackner/R2E3/retorfit/4.JPG

http://www.telusplanet.net/public/shackner/R2E3/retorfit/5.JPG

http://www.telusplanet.net/public/shackner/R2E3/retorfit/6.JPG

http://www.telusplanet.net/public/shackner/R2E3/retorfit/7.JPG

legendboy
02-20-2012, 03:24 PM
http://www.telusplanet.net/public/shackner/R2E3/retorfit/8.JPG

Enough work for one night

I was not looking forward to cleaning it. Couple saturdays ago my wife had to work so I called grandma to come watch the kiddies so I could have the day to dig in.

7 hours, 10 cans of brake cleaner and 5 pounds of rags later :D

http://www.telusplanet.net/public/shackner/R2E3/retorfit/9.JPG

http://www.telusplanet.net/public/shackner/R2E3/retorfit/10.JPG

legendboy
02-20-2012, 03:29 PM
I took the old cabinet that housed the drives and had it sandblasted. Had buddy at my work spray it with baked enamel finish.

Making some modifications

http://www.telusplanet.net/public/shackner/R2E3/retorfit/11.JPG

http://www.telusplanet.net/public/shackner/R2E3/retorfit/12.JPG

http://www.telusplanet.net/public/shackner/R2E3/retorfit/13.JPG

I was really hoping to get more done this weekend. I bought a bag of pc case standoff's and screws but as it turns out the screws are too big for the mounting holes on the drives. Hopefully I can find some smaller ones locally tomorrow.

legendboy
02-20-2012, 03:31 PM
Snagged this ACS350 on ebay a couple years ago for $100 buy it now.

Finally have a use for it

http://www.telusplanet.net/public/shackner/R2E3/retorfit/14.JPG

I had another ABB drive that I used on my lathe. They seem like good units

legendboy
02-20-2012, 04:04 PM
Here is a screen shot of my first design of the control interface. I am going send the final flat patterns out and have them laser cut.

I bought a 15" panel mount ELO touch screen on ebay. Came out of a photo booth kiosk.

Also grabbed a really nice panel mount Indukey KS7236 membrane keyboard on ebay for $50. (retail is 550 Sterling!)

Also purchased Intel D525MW atom, Intel solid state HD

I think i want to have the keyboard angled slightly up so this will likely change.

http://www.telusplanet.net/public/shackner/R2E3/Control/concept%201.JPG

legendboy
02-20-2012, 11:53 PM
any tricks to getting the wires in the 3rd pic up to bend to my will. they are also a bit short for what i had planned

they have zero memory

i could strip the outer insulation off as soon as the cables enter the enclosure but the drive manual says bring insulated cable right to the drive.

the wire type is 5 twisted pairs each with their own foil shield and drain wire in moulded cover/insulation

i am not sure if i will run into all sorts of emi issues if i do that, anybody have any insight on tha



oh yea i am going to be posting tons of questions here so please help me out

macona
02-21-2012, 12:19 AM
Have the wires lost their flexibility? You could heat them up with a heat gun. Just don't go crazy. Or replace the cable back from the encoders.

As long as you don't have the encoder wires next to power wires, especially the motor ones, you should be fine.

A friend is probably going to buy the granite drives to replace the geckos on his router. Hopefully they work better. Also looking at using one of the kflop controllers.

legendboy
02-21-2012, 12:32 AM
Have the wires lost their flexibility? You could heat them up with a heat gun. Just don't go crazy. Or replace the cable back from the encoders.

As long as you don't have the encoder wires next to power wires, especially the motor ones, you should be fine.

A friend is probably going to buy the granite drives to replace the geckos on his router. Hopefully they work better. Also looking at using one of the kflop controllers.

I will try the heatgun once I get them ready for their final path. I would like to use all the existing cable if i can. Is it ok I to add length to individual wires if needed? they would be soldered and shrink wraped

macona
02-21-2012, 02:45 AM
Solder and shrink wrapped. Keep them twisted and paired all the way up to the driver if possible.

Sparky_NY
02-21-2012, 08:19 AM
any tricks to getting the wires in the 3rd pic up to bend to my will. they are also a bit short for what i had planned

they have zero memory

i could strip the outer insulation off as soon as the cables enter the enclosure but the drive manual says bring insulated cable right to the drive.

the wire type is 5 twisted pairs each with their own foil shield and drain wire in moulded cover/insulation

i am not sure if i will run into all sorts of emi issues if i do that, anybody have any insight on tha



oh yea i am going to be posting tons of questions here so please help me out

I also used the original bridgeport cables. Even though your manual says to bring the insulated cable right to the drive, the outer jacket is electrically non functional, I stripped it and bundled with tie wraps. As for the motor power cable, you can strip the insulation but need to maintain the shield.

I have the exact same VFD as you bought. It has worked fantastic, one of the nicer vfd's I have seen. I put external braking resistors into use.

Good luck, looks like your coming along nicely.

legendboy
02-21-2012, 06:15 PM
What I may do is bring the original bridgeport cable just inside wire ducting, tie it down and then switch to new 2 conductor shielded for each pair to run where I need it to go.

My local electronics place has shielded shrink tubing i could use to cover the exposed transition area for extra isolation. Sounds like this may be over kill tho.

Have my first evening class at SAIT "intro to cnc controllers" tonight, pretty excited.

macona
02-22-2012, 01:53 AM
One thing you should add to the control panel is a MPG. It is so, so, so much better for jogging and touching off than the keyboard.

http://www.cnc4pc.com/Store/osc/product_info.php?cPath=40&products_id=163

legendboy
02-22-2012, 10:36 AM
One thing you should add to the control panel is a MPG. It is so, so, so much better for jogging and touching off than the keyboard.

http://www.cnc4pc.com/Store/osc/product_info.php?cPath=40&products_id=163

I have been debating on getting a hand held pendant as well


This is what they are teaching me how to use at this night class. We are already into manually programming and I didn't take the prereq. so i might fall behind but whatever it will be good exposure

http://www.telusplanet.net/public/shackner/R2E3/simulator.JPG

legendboy
02-22-2012, 11:01 AM
Whats everybodys thoughts on having the vfd inside the control cabinet?

MaxHeadRoom
02-22-2012, 12:13 PM
I have installed 3 VFD's all in the same enclosure with the controller.
I also used 3ph inductors on the VFD output.
http://www.automation.siemens.com/doconweb/pdf/840C_1101_E/emv_r.pdf?p=1
Max.

scmw
02-22-2012, 01:36 PM
Hey LB,

You're making great progress and it looks like a great machine. You should have a ton of fun with that one.

Black Forest
02-22-2012, 02:03 PM
Hey LB,

You're making great progress and it looks like a great machine. You should have a ton of fun with that one.


Hey our wives might read that. We don't want them to know it is fun and we enjoy ourselves.

Please edit your last statement to read, You should be able to get a lot of work done on that machine.

Do it quick.

amateur
02-22-2012, 09:06 PM
I also used 3ph inductors on the VFD output.
http://www.automation.siemens.com/doconweb/pdf/840C_1101_E/emv_r.pdf?p=1
Max.
What are 3ph inductors if I may ask ?

macona
02-22-2012, 09:14 PM
A pendant is very nice. I have a Fadal labeled Micronor MR175 that has been reprogrammed by Peter Homann

http://www.micronor.com/products/files/MR175/MDS_MR175.pdf

http://www.homanndesigns.com/store/index.php?main_page=product_info&cPath=15&products_id=28

Its great. Rugged and sealed.

amateur, the inductor is placed between the vdf and the motor, especially in long wire runs, to eliminate harmonics.

MaxHeadRoom
02-22-2012, 09:37 PM
What are 3ph inductors if I may ask ?

http://www.automationdirect.com/adc/Overview/Catalog/Drives/AC_Drive_%28VFD%29_Spare_Parts_-a-_Accessories/AC_Line_Reactors

Also called reactors.
Max.

legendboy
02-23-2012, 11:55 AM
I thought an inductor went between the mains supply and the inverter which helps reduce the harmonics going back thru the mains and affecting other emi sensitive equipment sharing the same mains power source?

or putting the inductor between the inverter and motor helps reduce noise traveling back to the controls main grounding point via motor frame ground?

MaxHeadRoom
02-23-2012, 02:10 PM
I thought an inductor went between the mains supply and the inverter which helps reduce the harmonics going back thru the mains and affecting other emi sensitive equipment sharing the same mains power source?


Yes it does that also, I have used both in some applications.
The output side is particularly useful for protecting non-vector rated motors.
Where there is a large quantity of VFD's on a particular supply, on the input side it aids in improving the power factor which can reduce the power cost drastically.
Here is an explanation from the link.

Line reactors used on the input side of a drive protect the AC drive from transient overvoltage conditions typically caused by utility capacitor switching. Input line reactors also reduce the harmonics associated with AC drives, and are recommended for all installations.

Line reactors used on the output side of a drive (load reactors) protect the motor insulation against AC drive short circuits and IGBT reflective wave damage, and also allow the motor to run cooler by "smoothing" the motor current waveform. Output reactors are recommended for operating "non-inverter-duty" motors and for any motors when the length of wiring between the AC drive and motor exceeds 75 feet.


Max.

legendboy
03-04-2012, 02:22 AM
progress is slow!

couple pictures from school

http://www.telusplanet.net/public/shackner/R2E3/retorfit/school%20lathes.JPG

i'd love to have a haas mini mill

http://www.telusplanet.net/public/shackner/R2E3/retorfit/school%20mills.JPG

saw this outside the millright doors and was picturing what kind of machine made the big gear

http://www.telusplanet.net/public/shackner/R2E3/retorfit/gears.JPG

wiring sub-d to old cable sucks

http://www.telusplanet.net/public/shackner/R2E3/retorfit/wiring.JPG

between hating my boss, having children under 5, and night classes i have been soooo tired

macona
03-04-2012, 05:59 AM
That big herringbone gear can be done with a standard gear hobbing machine like so:

http://www.youtube.com/v/x2Hwe6-EXug

The other type like the smaller ones are done with a shaving type cutter, something like this:

http://www.youtube.com/v/d7uoNqzsc2E

legendboy
03-05-2012, 01:05 PM
^ cool!

So how critical is using shielded cable from ac drive to motor?

I was looking for some locally but nothing is available. All the people I talk to say they use regular R90 cable in Tek or plain old cabtire cable

MaxHeadRoom
03-05-2012, 02:12 PM
Some are using shielded cable, I have a link some where, but over years, the many VFD's I have installed I have never used shielded, just TEW single conductor stranded and twisted tightly, the ground conductor ran alongside.
Out on the machine I used Liquid seal flex metallic conduit.
Max.

legendboy
03-05-2012, 02:53 PM
I grabbed some 5-10awg out of a scrap bin I think should work. Hopefully its long enough

MaxHeadRoom
03-05-2012, 02:55 PM
The shielded stuff is sold by Igus, the same as the cable carrier maker.
http://www.igus.com/wpck/default.aspx?pagenr=3532&C=US&L=en
Max.

legendboy
03-05-2012, 03:37 PM
^thats nice stuff
I could order this but it takes a week + to get here

https://edeskv2.belden.com/Products/index.cfm?event=printPrev&pnum=29502&ut=english

Trying to find as much locally as I can so I don't stall out on it

legendboy
03-07-2012, 11:16 AM
I am a little unsure of how to run the main power for my mill

I have a 3 phase fused disconnect switch that I bought and planned on using that to switch 240v single phase input power.

Not sure if by switching that, turns the machine power on or if I should have another "on" switch that powers a contactor to turn machine power on. (once the main disconnect switch has been turned on)

I also have a bunch of din mount fuse holders that I would like to use but am un sure of exactly what should all be fused?

I have 3 power supplies:
1 12/5v logic power supply (sola)
1 12v 80w ps to power new 12v cooling fans
1 160vdc servo ps

Should I have the input or output on these fused? or both?

rdfeil
03-07-2012, 12:01 PM
Legendboy,

There are several schools of thought on what you have asked. This is my thought...

For the incomming power, the disconect switch will do what you want and should be used as the first thing in the incomming power circuit. This will allow you to turn the mill on and off and also provide a safety disconect to the machine. I would also use a contactor after the disconect to allow you to put an on/off switch closer to the operator position and also give you easy access to add an emergency stop switch to the machine (always a good idea in case of programming errors or just bad luck).

As for fusing the power supplies....
You should fuse the input power to EACH power supply seperately. As for fusing the output side some do and some don't. I don't feel it is needed, but some codes require it to be proper industry standard. In any case it would not hurt to fuse the output side if you already have the parts.

Just my thoughts, others may feel differently and all thoughts should be considered.

legendboy
03-07-2012, 12:45 PM
rdfeil, thanks for the reply

another question, if i use on and off push buttons on my control panel to actually switch power via contactor: how do the momentary on off buttons work exactly?

does it depend on the type of contactor i use?

rdfeil
03-07-2012, 01:15 PM
Legendboy,

Do a search for "3 wire motor control". This is the control circuit you are looking for. Basicly what happens is the Stop switch is normally closed and the Start switch is normally open and you need an extra normally open contact on the contactor, this can be either an aux switch on the contactor OR an unused main contact set.

The stop switch is wired in series with the start switch then to the contactor coil. The extra normally open switch is wired across the start switch.

When you push the start switch the power flows through the closed stop switch, the now closed start switch then on to the contactor pulling it in. This powers up the machine and closes the extra switch contact shorting out the start switch thereby keeping the contactor closed when you release the start switch. When you push the stop switch you open the circuit which drops the contactor out thereby opening the extra switch (and powering down the machine). Now everything is back to the way it was waiting for you to push the start button.

With this control system several things are in your favor...

1) If power is interupted for any reason (power failure etc.) the machine will not restart without you pushing the start button.

2) Adding an Emergency Stop button is as sinple as wiring it in series with the main stop button (normally on the incomming power side).

3) If you add a low voltage transformer and use an appropriate contactor coil you can run all of the start/stop/emergency stop functions with low voltage wiring.

I hope this helps.

Edited to add....

I refer to start/stop where I should really say On/Off because this is actually controling the main power to the machine NOT the starting and stopping of the CNC controls (spindle, drives etc...), that is a seperate function.

MaxHeadRoom
03-07-2012, 01:59 PM
I guess you can't post a PDF here?
Here is a link to it, Square D/Telemecanique wiring examples.
http://static.schneider-electric.us/docs/Machine%20Control/0140CT9201.pdf
Max.

MaxHeadRoom
03-07-2012, 03:25 PM
another question, if i use on and off push buttons on my control panel to actually switch power via contactor: how do the momentary on off buttons work exactly?

does it depend on the type of contactor i use?

The DIN style contactors are very compact, if you pick one up on ebay similar to Telemecanique (my favourite) you can get add on NO/NC auxilliary contacts that clip in the front if the contactor comes without it, you can also get 24vdc coils for low voltage control circuits, 24vdc is the pretty much standard now for control.
Max.

legendboy
03-07-2012, 04:22 PM
Thanks so much for the help guys

I bought a standard 40a 3 pole, 24vac coil contactor

so in the diagram below:

the lower M in the middle is the 3rd unused L3 contact on the contactor?

the M above the circle on RHS is the 24v contactor coil?

what is OL?

http://www.telusplanet.net/public/shackner/R2E3/retorfit/3%20wire.JPG

rdfeil
03-07-2012, 04:57 PM
First off.. Max thanks for posting the link.

Legendboy,

You are right with what you said, however...

First, remember that you have a 24 VAC contactor so the L1 and L2 connections will be to 24 volts (transformer).

Second, The M contact (middle lower) could be the unused L3 contact on your contactor, but it would be better if you used a Normally Open Aux contact as Max described above. Your contactor may already have one on the side, if not one will be available. Using the Aux contact keeps the 24 volt stuff away from the line voltage and is safer and easier to understand in the future.

Last, the OL is the motor overloads. They are used to protect motors when the contactor is used to switch motors. In your case they are not needed or used, just ignore them and wire the coil directly to L2 (in your diagram) remember 24 volts NOT actual line voltage.

Sorry to harp on the voltage, just don't want you to get a bad surprise :eek: .

MaxHeadRoom
03-07-2012, 05:06 PM
what is OL?



O/L = Over Load, they are usually fitted on the bottom of a motor contactor and open up the coil if the O/L trips due to motor fault etc.
The method of placing the O/L in the 'neutral' or common grounded side of the coil is frowned on now, as if the neutral is grounded and a ground appears on the this side of the O/L it is defeated.
This was done originally as a easy way to wire it in on Contactor P.B. stations.
The recommendation now is that it is inserted on the 'live' side of the coil.
Max.

legendboy
03-07-2012, 05:23 PM
First off.. Max thanks for posting the link.

Legendboy,

You are right with what you said, however...

First, remember that you have a 24 VAC contactor so the L1 and L2 connections will be to 24 volts (transformer).

Second, The M contact (middle lower) could be the unused L3 contact on your contactor, but it would be better if you used a Normally Open Aux contact as Max described above. Your contactor may already have one on the side, if not one will be available. Using the Aux contact keeps the 24 volt stuff away from the line voltage and is safer and easier to understand in the future.

Last, the OL is the motor overloads. They are used to protect motors when the contactor is used to switch motors. In your case they are not needed or used, just ignore them and wire the coil directly to L2 (in your diagram) remember 24 volts NOT actual line voltage.

Sorry to harp on the voltage, just don't want you to get a bad surprise :eek: .



O/L = Over Load, they are usually fitted on the bottom of a motor contactor and open up the coil if the O/L trips due to motor fault etc.
The method of placing the O/L in the 'neutral' or common grounded side of the coil is frowned on now, as if the neutral is grounded and a ground appears on the this side of the O/L it is defeated.
This was done originally as a easy way to wire it in on Contactor P.B. stations.
The recommendation now is that it is inserted on the 'live' side of the coil.
Max.

Thanks for taking the time to explain this stuff, greatly appreciated!!

legendboy
03-07-2012, 11:19 PM
I was easily able to get that circuit put together for testing but I think I am going to get a din mount contactor like max suggested.

I want to have my off button illuminated when the main machine power is on but the machine is off. Need to be have a nc aux contact to do that.

MaxHeadRoom
03-07-2012, 11:26 PM
In that case it is common to have a green light on the ON and RED on the off button.
Max.

legendboy
03-08-2012, 12:10 AM
Yep that's what I bought today. They are a lot nicer then the old ab ones I had kicking around.

MaxHeadRoom
03-08-2012, 11:53 AM
Another useful link to avoid 'noise'.
http://www.automation.siemens.com/doconweb/pdf/840C_1101_E/emv_r.pdf?p=1
Max.

legendboy
03-12-2012, 01:38 AM
obligatory weekend update

http://www.telusplanet.net/public/shackner/R2E3/retorfit/march%2011.jpg

progress has been slow because my life is busy, and I don't get as much time as i would like to have to finish this up. I am really excited to get this thing up and running :D

legendboy
03-12-2012, 02:08 AM
Another useful link to avoid 'noise'.
http://www.automation.siemens.com/doconweb/pdf/840C_1101_E/emv_r.pdf?p=1
Max.

max do you have the simodrive grounding pdf?


Some are using shielded cable, I have a link some where, but over years, the many VFD's I have installed I have never used shielded, just TEW single conductor stranded and twisted tightly, the ground conductor ran alongside.
Out on the machine I used Liquid seal flex metallic conduit.
Max.

was this for classified area? did you liquid seal?


O/L = Over Load, they are usually fitted on the bottom of a motor contactor and open up the coil if the O/L trips due to motor fault etc.
The method of placing the O/L in the 'neutral' or common grounded side of the coil is frowned on now, as if the neutral is grounded and a ground appears on the this side of the O/L it is defeated.
This was done originally as a easy way to wire it in on Contactor P.B. stations.
The recommendation now is that it is inserted on the 'live' side of the coil.
Max.

i think i kept tripping mine on my standard modern lathe. i have a bunch of turning to do in some stages. First stage was a panic so i wired my rpc, first time i have used rpc power since i sold my vfds.

I kept having to reset it intermittently and scrapped a few parts because of it. Any advice on this would be greatly appreciated!

Someone also told me last week that for single phase in, three phase out VFD'S the vfd should be sized larger then the specified value given in the literature

macona
03-12-2012, 04:22 AM
All of my machines have integrated PCs right to the machine. When the power comes on the 5v line turns on a SSR for the main contactor for the machine. The drives have their own contactors that are linked in with the estop and the charge pump circuit. The computer is powered off the mains before the main SSR by either a 220v to 110v line transformer or the computer power supply set to 240v input.

MaxHeadRoom
03-12-2012, 12:33 PM
max do you have the simodrive grounding pdf?



I have it, but didn't the link work?



was this for classified area? did you liquid seal?


Liquid seal flex is relatively cheap and durable, you can get the super flexible for cable carriers etc.
I use TEW or MTW single conductor stranded control wire, metalic flex Conduit for shielding.


Someone also told me last week that for single phase in, three phase out VFD'S the vfd should be sized larger then the specified value given in the literature

Check with the Manuf lit. most now do not require de-rating below 5hp.
Max.

legendboy
03-14-2012, 12:20 PM
Want to get going on my operator panel but I am having to wait for my pulse generator in the mail. Got a sweet one off ebay. Hopefully it is in as good of shape as in the pictures

In other news, I think I am getting a HAAS simulator from my school lol. Supposedly there are 4 older ones in storage that are not being used anymore and I asked my teach.

That would be sweet to have on my desk at work :D

legendboy
03-14-2012, 11:22 PM
anybody have any insight into how much ramp down distance I should leave for my xy limit switches between estop and end of travel?

I'm thinking a 1/4" would be enough but that's a guess

MaxHeadRoom
03-14-2012, 11:46 PM
Thats roughly right,but you can get an idea for each axis by jogging each at max rate and hitting the E-stop at a given or marked point and seeing how far the travel is past the mark.
Max.

legendboy
03-15-2012, 12:08 AM
good idea max

i just measured the Bridgeport switches, they are a hair under .4" apart between home and estop

MaxHeadRoom
03-15-2012, 12:36 AM
But that is between home and E-stop, not between OT and end of travel?
The home does not limit over all travel stroke but the OT SW does.
Max.

macona
03-15-2012, 07:28 AM
Limit switches are not tied into the e-stop. They have their own inputs into the controller.

The machine will stop very fast when homing so the amount of space between home and limit can be rather small.

legendboy
03-15-2012, 10:29 AM
i'll post up a few pictures tomorrow to clarify how the bridgeport switches are setup

MaxHeadRoom
03-15-2012, 10:36 AM
How you set the limits up is up to you, whether you want a hard wired stop or software stop, I generally wire them in the hardware E-stop series string.
The control start push button overrides them in order to jog off the limit.
Max.

legendboy
03-15-2012, 10:58 AM
Each xy limit switch assembly has 2 switches built in, one NO and one NC. Close to the end of each travel direction there are 2 adjustable switch "actuators" or activators.

I think the home switch is NO and is very close to mechanical end of travel. This makes sense to me because homing is done at slow speed so very little distance left is needed.

I am assuming the NC switch is tied into the estop circuit (or will be anyways) and I have about an inch adjustability on it for ramp down before EOT.

MaxHeadRoom
03-15-2012, 11:56 AM
Home switches can be otional N.O./N.C., if running the O.T. in series then they would be N.C. and are N.C. as a rule for fail safe.
It also depends on whether the controller you are using uses the encoder marker for home, or just the home switch as Mach does.
When the marker is used, there is usually a fast move until the home switch is seen and then a creep speed to find the 1/rev marker.
Max.

legendboy
03-15-2012, 12:07 PM
I could set the granite drives up that way but I am going to let USBCNC take care of homing and estop (which relies on the switches and not encoder lines)

legendboy
03-19-2012, 11:18 AM
Quick question, Can i operate a 24vdc contactor coil with 24vac?

MaxHeadRoom
03-19-2012, 12:17 PM
The impedance of the DC coil on AC is going to be higher so the contactor armature may not pull in or if it does, hold in weakly or chatter, put a simple $3.00 bridge on the coil.
On AC a fast pull in relies on the low DC resistance of the coil causing high inrush and the time it takes for the armature to close after which the impedance becomes effective and limits the current, introduce the high resistance of a DC coil and you may get the effect above.
Plus the shading ring is absent on a DC contactor coil that prevents chatter on AC contactors.
Max.

legendboy
03-19-2012, 12:50 PM
Thanks max

legendboy
03-20-2012, 01:35 PM
pulse generator came in. going to get my control sheet metal going this week :)

http://www.telusplanet.net/public/shackner/R2E3/Control/pulse%20gen.JPG

now waiting for a 50 pin header to terminal BOB in mail and then I pretty much should be done purchasing stuff

legendboy
03-28-2012, 11:55 AM
made some smoke last night

i wanted to power up my control to check limit switch and estop functionality so i went ahead and connected main power with only fuses in to power the control ps.

i didn't want to listen to my contactor buzzing so i disconnected one leg of the 24v coil leads from it while power was on

my 24v transformer started smoking as soon as i did that. i think this happened because i am powering the little transformer 240v so one hot leg was still attached

not sure exactly why smoke tho :o

MaxHeadRoom
03-28-2012, 12:33 PM
There is a piece of the puzzle missing, no load should = no current, it sounds like something shorting the transformer secondary?
It Doesn't matter if the primary is still connected?
Was it the 24v or the 240v side you disconnected?
Max.

legendboy
03-28-2012, 06:22 PM
it was the 24v side

:confused:

legendboy
03-28-2012, 08:03 PM
The transformer is marked:

Pri: wht-com
Blk-120v
Red-208v
Org-240v

I had 240v mains connected to black and orange

MaxHeadRoom
03-28-2012, 08:48 PM
Looks to me like it should have been wht and org you had 240v connected to a 120v input.
Max.

legendboy
03-28-2012, 10:44 PM
Noob mistake!

I am doubting the layout of my electronics after reading thru the vfd manual. Just doesn't seem like I have enough room to follow the recommended electrical installation instructions. Wish I had more experience with building a control.

legendboy
03-28-2012, 11:07 PM
My main concerns are having my controller 5" away from un shielded drive motor cable and also an inch away from mains entering the cabinet.

I also bought a nice 50 pin header breakout board that can only mount below the vfd and power cables. This puts un shielded ribbon cable and control wiring even closer to the vfd...

Drive motor cable and in coming mains also enter/leave the cabinet at the same point and also run parallel beside each other for about 6". Manual says that is also a no no

legendboy
03-28-2012, 11:20 PM
Am I over thinking this?:D

macona
03-29-2012, 01:06 AM
Yes, you are. Worry about that if it causes a problem. It probably won't. Thats one advantage of using 24v for signals. Higher signal to noise ratio.

legendboy
03-29-2012, 06:24 PM
Could you offer any suggestions on my plan?

This is very elementary. I have never done any schmatics of any kind, whipped it up in about 30mins from memory

Start / Stop buttons should read On / Off

http://www.telusplanet.net/public/shackner/R2E3/Control/SCHEMATIC1.jpg

macona
03-30-2012, 01:23 AM
That's about it. One thing I do is I leave the VFD powered up all the time. There is virtually no current draw so it does not care. And I am a big believer in leaving things on. Things seem to blow out more when they are power cycled. A lot of servos keep track of power on cycles in NVRAM.

On my little mill and lathe I took 5 and 12v right off the computer power supply rails. Most newer PC power supplies have power to spare several times over for what we want. With my mill I needed -12v as well for the pixie boards that controlled the old analog servos. To get that I took an ATX extension and spliced in wires by soldering and heat shrinking. At the time I had a pin extractor tool for the mate-n-lok connectors.

For you all you need to do is tie into a hard drive connector. This has an advantage of eliminating any possibilities of ground loops.

legendboy
03-30-2012, 10:25 AM
thanks for the feedback!

i was wondering about leaving vfd power on. I have always left my vfd's on all the time.

legendboy
04-01-2012, 01:22 AM
Had to change the layout. First time I have ever tried to design something like this and was not happy with the first attempt.

I am much happier with this new layout. Things like this keep me awake at night so.....

http://www.telusplanet.net/public/shackner/R2E3/retorfit/new%20layout.jpeg

MaxHeadRoom
04-01-2012, 11:25 AM
Looking good!
It is also helps to keep a supply of Brown Ale on hand I see.;)
Max.

scmw
04-01-2012, 01:57 PM
I really like the clean layout of your control cabinet. We have a Series II NC that currently runs with Mach 3. We're going to be doing a restoration and improvement project on it later this summer/fall. I will be using your project notes and pics as part of the process.

Very nice work!

MaxHeadRoom
04-01-2012, 02:47 PM
Its amazing how many items are made to fit on DIN rail, even small power transformers.
Max.

rdfeil
04-01-2012, 03:28 PM
Legendboy,

Looks good. One suggestion, Look at moving the contactor and high voltage fuses up into the upper cabinet area. By doing this you will effectively isolate the low voltage DC controls from the high voltage feeds. The only thing left would be the VFD output wiring to the motor and this could easily stay to the right side of the cabinet, away from the drives, BOB, Etc. The 24 volt On/Off controls would be kept in the upper cabinet also...

Just a thought.

legendboy
04-01-2012, 11:56 PM
I really like the clean layout of your control cabinet. We have a Series II NC that currently runs with Mach 3. We're going to be doing a restoration and improvement project on it later this summer/fall. I will be using your project notes and pics as part of the process.

Very nice work!

Sweet I will do a build summary at the end



Legendboy,

Looks good. One suggestion, Look at moving the contactor and high voltage fuses up into the upper cabinet area. By doing this you will effectively isolate the low voltage DC controls from the high voltage feeds. The only thing left would be the VFD output wiring to the motor and this could easily stay to the right side of the cabinet, away from the drives, BOB, Etc. The 24 volt On/Off controls would be kept in the upper cabinet also...

Just a thought.

I thought about that but I have a nice fan panel that mounts at the front of the top of the cabinet. I put in two really quiet 12vdc fans in the enclosure that blocks the top portion opening.

Anything that I may need access to I want to keep easily accessible.

I have things like auto lube, spray mist and flood coolant etc... that I want to wire in eventually

I bought Belden 29501 vfd cable also just need to buy some strain reliefs. It cost me $72 but I feel better having bought it.

Max I keep my garage beer fridge stocked up good :D

legendboy
04-02-2012, 12:05 AM
Wow I actually did that last post with my playbook. Was very annoying :mad:

legendboy
04-02-2012, 12:23 AM
..........

legendboy
04-10-2012, 06:20 PM
updated the pics below

legendboy
04-11-2012, 04:21 PM
turned out good. the enclosure should be ready tomorrow.
I am going to get everything installed and wired up then disassemble before I send it out for powder coat. Thinking white for the front panel and grey rear enclosure box

hopefully make some good progress this weekend :p

http://www.telusplanet.net/public/shackner/R2E3/Control/panel%20front.jpg

http://www.telusplanet.net/public/shackner/R2E3/Control/panel%20back.jpg

MaxHeadRoom
04-11-2012, 07:35 PM
I get a local company to make my panels up in reverse engraved lamacoid, all the legends and logo if you want can be in different colours, and does not rub off or get grease contaminated.
Put the Yellow circle around the E-stop!
Max.

legendboy
04-11-2012, 09:25 PM
Max, so you get the entire surface of a panel cut in lamacoid, paint the metal panel and then overlay?

I considered getting a brushed ss overlay cut but figured it would get super grimy and dirty.

Do you have any pics of your creations?

DICKEYBIRD
04-11-2012, 09:49 PM
Right about now is when the excitement kicks in on my projects and I never spend the time to get that professional look you guys get.

It must be the beer that mellows you out and gives you the patience to do it right.:D Doesn't work for me though; things get worse.:rolleyes:

MaxHeadRoom
04-11-2012, 10:11 PM
I don't paint the panel, the Lamacoid is a special reverse engraved type that reveals the front transparent layer, this is then filled with paint to your colour of choice, this way it is possible to have multi-colour legends or logo's.
I will see if I can dig an example up.
Max.

MaxHeadRoom
04-11-2012, 10:27 PM
How come I cannot post attachments????
Max.

legendboy
04-11-2012, 11:33 PM
I don't paint the panel, the Lamacoid is a special reverse engraved type that reveals the front transparent layer, this is then filled with paint to your colour of choice, this way it is possible to have multi-colour legends or logo's.
I will see if I can dig an example up.
Max.

That sounds pretty neat

If you want us can email some pics and I will host them and post them

MaxHeadRoom
04-12-2012, 09:49 AM
I have a good local guy that specializes in Electrical Panels.
I just send him a DWG file.
Max.

legendboy
04-12-2012, 10:08 AM
Posting these on Max's behalf

http://www.telusplanet.net/public/shackner/R2E3/Control/Max%20Pics/1.jpg

http://www.telusplanet.net/public/shackner/R2E3/Control/Max%20Pics/2.jpg

http://www.telusplanet.net/public/shackner/R2E3/Control/Max%20Pics/mpg.jpg

legendboy
04-12-2012, 10:09 AM
Those are definitely pretty cool Max. I never would have thought to do that but now that I see your pictures I do remember seeing that style before

Wonder if I have anybody locally that does that :D

MaxHeadRoom
04-12-2012, 01:53 PM
There are probably going to be local lamacoid services but many have just a 12" or 18" tables.
Max.

legendboy
04-12-2012, 07:25 PM
Do you remember roughly what those cost you?

I sent a drawing file to a local place for a quote. Would be nice to have something to compare the price with.

MaxHeadRoom
04-12-2012, 07:37 PM
The average is around $85.00, I think the most has been around $150.00 for a fancy multi-colour one.
I also get him to do all the aperture cut outs.
Max.

legendboy
04-13-2012, 10:47 AM
this is the drawing i sent legacy marking. they gave me a price of $210 + tax

this would overlay the entire front panel (470mm x 700mm)

kind of on the fence

http://www.telusplanet.net/public/shackner/R2E3/Control/lamacoid.JPG

MaxHeadRoom
04-13-2012, 01:28 PM
What format do you have them in? I could always check with my guy and see what he says, although by now his prices could have risen?
Max.

legendboy
04-13-2012, 03:39 PM
dwg or dxf

MaxHeadRoom
04-13-2012, 03:40 PM
If you want to send it over I can check with him?
Max.

legendboy
04-13-2012, 05:17 PM
forwarded you the email

Thanks for checking for me!

legendboy
04-13-2012, 11:09 PM
gonna weld this up tomorrow

i like welding when i am drinking beer however the i usually end up breaking out the grinder in the morning :D

http://www.telusplanet.net/public/shackner/R2E3/Control/box.JPG

legendboy
04-18-2012, 12:16 AM
Is it preferable to run 240v mains and 24vac 3 wire on/off in the same teck cable to the user panel or 240v mains separate and 24vac in teck with shielded signal cables?

Run all 3 separate?

MaxHeadRoom
04-18-2012, 10:38 AM
Teck cable is not my favorite for control wiring, but IIRC the minimum rating for teck insulation is 600v so you should be OK there, and if just running AC 240 & 24vac feeds there is no problem with interaction.
Max.

legendboy
04-18-2012, 11:05 AM
Thanks so much for all your help max!

I should have said teck type conduit, will run my own cables thru it

MaxHeadRoom
04-18-2012, 12:07 PM
Well if the insulation rating of the conductors is OK then you should be good.
If you do any extensive control wiring, it pays to get hold of a copy of the NFPA79 booklet, Electrical Standard for Industrial Machinery Control wiring .
Max.

legendboy
04-19-2012, 03:45 PM
Managed to find the 2002 version on pdf free download. Should make for some good bathroom reading

If anybody wants a copy let me know



Picked up some liquid tight conduit and strain reliefs, install that tonight

John Stevenson
04-19-2012, 07:44 PM
Posting these on Max's behalf

http://www.telusplanet.net/public/shackner/R2E3/Control/Max%20Pics/1.jpg

http://www.telusplanet.net/public/shackner/R2E3/Control/Max%20Pics/2.jpg



Max,
Where do these keyboards come from please.

MaxHeadRoom
04-19-2012, 11:41 PM
They were made by industrial keyboard/switch manuf http://www.ctielectronics.com/industrial-products/industrial-keyboards/index.php
I bought a quantity some time back as they were needed for custom built systems and I needed the quality, they were not cheap.
The one piece rubber overlay is replaceable, although I am not sure if they make this model any more but there are a few manuf out there with similar products.
Max.

John Stevenson
04-20-2012, 06:31 PM
Many thanks for the reply.

legendboy
04-23-2012, 01:07 AM
Made a bit of progress

Got the control panel together temporarily. Ran power to it, 3 wire on off with illumination in. The contactor in the cabinet is working perfectly

Ran liquid tight conduit, one for power, one for control

http://www.telusplanet.net/public/shackner/R2E3/Control/progress/liquid%20tight.JPG

When main power is on this is what the control looks like

http://www.telusplanet.net/public/shackner/R2E3/Control/progress/power%20on%20but%20off.JPG

Push green button and then this

http://www.telusplanet.net/public/shackner/R2E3/Control/progress/green%20button.JPG

legendboy
04-23-2012, 01:07 AM
Power and connection between the pc and the motion controller

http://www.telusplanet.net/public/shackner/R2E3/Control/progress/controller%20power.JPG

John Stevenson
04-23-2012, 04:04 AM
Why does your screen look different to the one on the Eding site ?

macona
04-23-2012, 07:48 AM
Looks like an infrared touch screen.

http://www.elotouch.com/Products/Touchscreens/CarrollTouch/default.asp

I have one on my cnc mill. Its okay. I prefer the touchscreen my mill which has the ELO SAW type touchscreen. My issue with the IR touch is they well register a hit before you touch the screen so it is real easy to hit the wrong thing. When double tapping to open a folder you have to make sure you pull your finger back far enough. Other than they they work fine. Does not matter if you hands are oily or got dirt on them which I have had an issue with on the SAW touch screen.

John Stevenson
04-23-2012, 08:05 AM
No I meant the colours and the logo at the bottom.

This is the Edding screen.

http://www.edingcnc.com/upload/im/Operate.jpg

legendboy
04-23-2012, 10:20 AM
Bert had some help re designing the gui from a professional tool maker.

Its easy to create custom icons as well for usbcnc software.

My touchscreen is surface wave

http://www.elotouch.com/Technologies/IntelliTouch/default.asp

Hood
04-23-2012, 11:22 AM
Had a ELO SAW screen on the lathe but had to junk the overlay as it could be activated by liquids. Never had a button get pressed with coolant but the cursor would follow and coolant that got on the screen from my fingers or splashes from the manual lathe opposite so I decided it best not to risk it.
Hood

legendboy
04-23-2012, 11:42 AM
Thanks for the heads up, something to test/watch out for

Mark McGrath
04-24-2012, 10:45 AM
Posting these on Max's behalf

http://www.telusplanet.net/public/shackner/R2E3/Control/Max%20Pics/1.jpg

http://www.telusplanet.net/public/shackner/R2E3/Control/Max%20Pics/2.jpg

http://www.telusplanet.net/public/shackner/R2E3/Control/Max%20Pics/mpg.jpg

Max,what did these panels control.Looks like it might be bending rolls to me.

MaxHeadRoom
04-24-2012, 11:12 AM
Top one Excello Mill, Acroloop motion card, bottom one is a Auto/Man Italian Rolling machine using Galil motion card.
Max

legendboy
04-24-2012, 11:18 PM
So I went to wire my mpg and I noticed its +12v, my control only has +5v available. Is it okay to use the same 12vdc control power I am using for servo drives?

Better yet if I am powering my control via usb can I use +12v from the pc ps?

MaxHeadRoom
04-25-2012, 12:19 AM
You can use the PC P.S. 12v, are you sure the output is 12v?
Some MPG use 12v supply but the output is 5v?
If the PC is close by I would run the 12v from one of the 4 pin supply sockets.
Max.

legendboy
04-25-2012, 12:23 AM
I wired it to 5v from the control and it works fine :)

legendboy
04-28-2012, 07:02 PM
Having a problem with my encoder wiring.
I powered my drives up ok but when the z axis encoder is connected I think it is shorting or grounding something out. The control power lights on my drives would dim almost to nothing.

As soon as I pulled the encoder subd connector off everything returned to normal.

I pulled the wiring apart and saw a mistake. I had A+- and b+- polarity reversed. Fixed that and triple checked everything else.

However the problem is still there. With the cable connected to the drive and powered up I get 4.7vdc on A+ & B+, 2.2vdc on A- & B-, 5vdc encoder power (these between mains ground)

I get continuity between mains ground and A+, B+, ground and +5v encoder power.

Not really sure what to do next I pulled the z axis servo off and insulated it from the machine. Connected the cable and everything works as intended. If I touch the servo to the machine I get the problem.

Can anybody suggest what might be causing this?

MaxHeadRoom
04-28-2012, 07:29 PM
A mix up on the respective differential outputs would not be the issue, this would just cause a directional phasing error, runaway etc.
It almost sounds like you have a problem on the encoder? I would remove the encoder and bench test it for valid differential outputs and for leakage to case.
2.2v on the /A /B is not right?
Continuity between the encoder 5v common and earth ground would not in and of itself be a problem, unless there is a partial short on the encoder 5vdc supply.
Again, I would verify the encoder isolated on the bench.
Presumably you are using the same supply for all encoders?
Max.

legendboy
04-28-2012, 09:33 PM
Yep I think I need to take it apart. I measure 5vdc between the servo frame and the machine

Erik Brewster
04-28-2012, 09:56 PM
I agree with max headroom.

The continuity between encoder 5v and ground is worry some. Also the 2.2v out on a- and b- is no good.

legendboy
04-28-2012, 10:28 PM
Everything is fine when the connector cap is off the servo and cables are connected so looking for a short

I checked continuity and the voltages from the motor end of the cable with the servo drive powered up

legendboy
04-28-2012, 11:24 PM
I have discovered:

The frame winding section and the encoder section of the servo are electrically isolated from eachother. There is no continuity between them.

On the encoder section the only pin that has continuity with fg is +5v

On the winding section the only pin that has continuity with fg is is fg (no fg pin on encoder section)

I also didn't have the 12v servo drive power supply grounded. This is a new power supply, a pretty dumpy one. I got it for free and had planned to use it to power my dc cooling fans. The sola power supply I bought does not have enough current to power all 3 servo drives at the same time fail

does this help with diagnosis? lol

legendboy
04-28-2012, 11:41 PM
Also, when the encoder cable is connected and drive powered there is +5vdc between the machine table and both winding and encoder sections of the motor

Anyways this only happens when the encoder cap is screwed on but I can't see a short

Erik Brewster
04-29-2012, 12:08 AM
By "fg", you mean frame ground, right? 5V shouldn't have continuity to any ground, so that is not good. If in doubt, you could do the same check on another encoder on the machine. You should not find continuity to ground.

Assuming you still are stumped after that, you might wire up a temporary encoder extension cable so you can connect only 5v return and 5v through your dmm's ammeter and watch the current. This would eliminate the idea that you have an encoder output that is shorted to something (negatives don't go close to zero is suspicous). Also, it could be a shorted encoder input on your cable or encoder counter on whatever hardware you are using. There is so much that could be going on -- this could shorten the troubleshooting list. You should be looking at 100 mA or less of encoder draw. If it's a lot more, you have a sick encoder or short -- you have looked for mystery metal slivers that have gotten in there and are shorting the works out, right? What type (part number?) of encoder is this? I am guessing from the vintage that it is some sort of Heidenhain incremental encoder with a tach (I only skimmed the previous pages in this thread).

Assuming that the encoder draw is ok with no signals, then hook the signals up, one wire at a time and look for the offender, by looking for a significant increase in current draw.

On the subject of mystery metal slivers, your circuit boards on the bottom of your cabinet make me nervous. They are begging to get shorted out if you were to let a single chip or other small piece of metal in there. Gravity would hold it against the board. A piece of lexan or other cover would be a nice piece of insurance. When you have this thing running, it's going to be a metal chip factory and all it takes is one to fall in when you open the cabinet...

Good luck on this one. You have done quite a nice job so far.

Erik Brewster
04-29-2012, 12:13 AM
Oops. Missed that encoder cap comment!

Are you saying that you can get the encoder plugged in, reading on your computer / controller with the encoder cap off and you put it on, and everything is unhappy?

If so, try putting the cap on by hand and watching the voltage. Is it happening when you put it on just a bit, or when you tighten the screws? Maybe a encoder cap screw is touching a bare wire / pcb? This is a stop and figure it out piece of info. Encoders should not touch the cap at all...

I suspect you have a short between 5v encoder and the encoder frame. It then gets shorted to the machine ground through the screw that you attach the encoder cap with. That is BAD. You are going to have to figure out where that short is coming from. Be nice to the encoder. They dont' like rough treatment.

legendboy
04-29-2012, 12:32 AM
By "fg", you mean frame ground, right? 5V shouldn't have continuity to any ground, so that is not good. If in doubt, you could do the same check on another encoder on the machine. You should not find continuity to ground.

Assuming you still are stumped after that, you might wire up a temporary encoder extension cable so you can connect only 5v return and 5v through your dmm's ammeter and watch the current. This would eliminate the idea that you have an encoder output that is shorted to something (negatives don't go close to zero is suspicious). Also, it could be a shorted encoder input on your cable or encoder counter on whatever hardware you are using. There is so much that could be going on -- this could shorten the troubleshooting list. You should be looking at 100 am or less of encoder draw. If it's a lot more, you have a sick encoder or short -- you have looked for mystery metal slivers that have gotten in there and are shorting the works out, right? What type (part number?) of encoder is this? I am guessing from the vintage that it is some sort of Heidenhain incremental encoder with a tach. (I only skimmed the previous pages in this thread).

Assuming that the encoder draw is ok with no signals, then hook the signals up, one wire at a time and look for the offender, by looking for a significant increase in current draw.

On the subject of mystery metal slivers, your circuit boards on the bottom of your cabinet make me nervous. They are begging to get shorted out if you were to let a single chip or other small piece of metal in there. Gravity would hold it against the board. A piece of lexan or other cover would be a nice piece of insurance. When you have this thing running, it's going to be a metal chip factory and all it takes is one to fall in when you open the cabinet...

Good luck on this one. You have done quite a nice job so far.

Yep fg is frame ground. The other 2 encoders have no problem on my machine. I tuned 3 motors all the same, completely disconnected from the machine

I just set the servo up again with the encoder cap screwed on and the connector and mounting flange loose, wires sticking out about a half inch

I powered everything up checked the servo drive status leds and my multi meter and all is good. I grab the connector and push it onto the encoder housing, get the error and short

I think i need to re do the wiring between the pcb and the connector. I can see the insulation cracking and exposed wires. I can easily fix this with my newly acquired soldering skills :D

I agree a lexan sheet over the servo drives is a good idea. I have been stripping cables in the cabinet like crazy and have thining about that alot. I have been blowing it out quite a bit with compressed air.

In retrospect I should have bought the din mounting kit for them and had everything in the same plane. I have heard these old series 1 bridgeports are stout machines, hopefully it makes me some money!

here is a pic of the old stiff cracking wiring. also see the (i think) retrofit led

http://www.telusplanet.net/public/shackner/R2E3/Control/progress/encoder%20wiring.jpg

MaxHeadRoom
04-29-2012, 12:35 AM
I agree it appears to be a short on the cap screw?
Which is odd as the screw generally goes into the base of the encoder and should not contact the electronics, it most likely is the cap touching one of the conductors as you replace it?
Normally the encoder supply is not referenced to gnd, it may be done in the controller or the 5v supply, but not usually in the encoder itself.
Looks like you are in for some detective work!
Oh I see you posted an update the same time.
Max.

legendboy
04-29-2012, 12:57 AM
i snipped those wires and the connector is in rough shape, one the the wires fell right out

Erik Brewster
04-29-2012, 03:05 AM
i snipped those wires and the connector is in rough shape, one the the wires fell right out
Be careful working on that stuff. Anything plastic on something that age is liable to break, not bend, as you are learning. I couldn't see the connector, but make sure it's mounted well -- you don't want fatiguing of the wires because pulling on the connector pulls on the wires, in turn.

Good thing you can fix it. :) Finding replacements can be a pain.

MaxHeadRoom
04-29-2012, 11:54 AM
That looks like one of the old Heidenhain incandescent light source types, there are quite a few manufacturers out there that make replacement infra red LED source servo mount encoders with the same case style, Hengstler is one that even supply the odd-ball connector that Heidenhain among other euro manuf. tended to use.
Max.

legendboy
04-30-2012, 01:32 AM
Some pics of the repair

http://www.telusplanet.net/public/shackner/R2E3/Control/encoder/IMG_2942.JPG

http://www.telusplanet.net/public/shackner/R2E3/Control/encoder/IMG_2943.JPG

http://www.telusplanet.net/public/shackner/R2E3/Control/encoder/IMG_2944.JPG

http://www.telusplanet.net/public/shackner/R2E3/Control/encoder/IMG_2945.JPG

legendboy
04-30-2012, 01:35 AM
http://www.telusplanet.net/public/shackner/R2E3/Control/encoder/IMG_2946.JPG

http://www.telusplanet.net/public/shackner/R2E3/Control/encoder/IMG_2948.JPG


i corrected a few other wiring mistakes and powered it up, no errors
connected my laptop to each drive and ran a few tests

so close to getting it running however i probably won't get it running until next weekend. i have to finish a turning job this week that i have been procrastinating on. at least its worth enough to pay for this project!! :D

MaxHeadRoom
04-30-2012, 10:59 AM
Good idea to replace all the conductors, over time the air borne oil particles harden the plastic, then when flexed or disturbed usually result in a fracture at a soldered joint.
Max.

legendboy
04-30-2012, 04:13 PM
That make sense. This servo was the only one that I removed the encoder cap from (to see pinout) and that probably caused the problem.

I can likely expect the same problems if I ever need to remove the caps off the other 2 motors. It was an easy fix tho, no more then an hour tops.

legendboy
05-03-2012, 10:13 AM
Got to spend some time last night tuning my z axis and ended up blowing up my braking resistor :o It happened while deep in thought, wasn't even doing anything. Scared the crap out of me :D My whole garage was full of the magic smoke lol

I am not exactly sure why it happened however after looking at my wiring I did see I forgot to tie -0v HV to earth. I think that is only to bring everything to the same PE...

I have a backup resistor but I should likely spend some time trying to figure out exactly why it happened before powering things back up

macona
05-03-2012, 12:00 PM
The ground should not have been an issue. It just burned out sitting there? That's not good.

legendboy
05-03-2012, 12:22 PM
yep I was running some torque tuning which went perfect, moved on to position tuning which was not going well. Played around with some trajectory planner settings, messed around with response amplitude, sample rate and buffer length for tests.

I was just sitting there thinking and the resistor popped

:confused:

MaxHeadRoom
05-03-2012, 12:27 PM
Normally if the braking circuit/resistor has gone open, you should still be able to run/test the drive otherwise run in slow operation, no sudden moves!
It could be that the device that switches the resistor, often a power FET has shorted for some reason?
I tend to agree the bonding of the supply -ve to ground or not should not be an issue?
Max.

legendboy
05-03-2012, 12:38 PM
so i should be looking for strands of copper wire cuts on my drives :o

MaxHeadRoom
05-03-2012, 12:47 PM
They don't help!;)
Max.

legendboy
05-03-2012, 02:55 PM
went home at lunch, carefully pulled the drive out, took the heat sink off and carefully inspected it with a flashlight. Tapped the corners onto a white sheet of paper

nothing!

I blew these things out super good before i powered everything up so i donno. The drive itself seems to still be ok and functional

going to open a trouble ticket with granite and see what they say

legendboy
05-03-2012, 03:45 PM
Thinking about it, I suppose it could be any of the drives shorting out since they are all wired together and share a common regenerative energy resistor.....

MaxHeadRoom
05-03-2012, 04:45 PM
I have never used Granite, but AFAIK they sell dual or single brushed drives, so is this a dual drive? the regenerative overvoltage usually comes in to play with fast deceleration?
Max.

legendboy
05-03-2012, 05:41 PM
The granite drives i bought only need a FW flash to drive 2 brush dc motors (called dualDC) (they will drive brush dc, bldc, ac & stepper motors with the standard FW)

I am using the drives in single axis mode, x & y drives are running parallel outputs to the servos to provide maximum current. In parallel output mode a breaking resistor can not be used because all power terminals are used to provide extra current.

However my Z axis is running in standard brush DC mode and I have the resistor setup on that drive. This allows the use of only one resistor between 3 drives.


http://www.telusplanet.net/public/shackner/R2E3/retorfit/resistor.JPG


the regenerative overvoltage usually comes in to play with fast deceleration?
Max.

yep

when i was doing position tests the z axis was not even visibly moving, just audible noises

Erik Brewster
05-03-2012, 08:11 PM
You might try disconnecting the DC bus sharing and putting the resistor on just the Z axis. Then keep and eye on the resistor temp. If the drive is bad, the resistor will get hot, fast. If it does not, try the tuning, still keeping an eye on the resistor temp.

Assuming the z axis works, repeat the test for the other axes until you find the bad drive.

Erik

legendboy
05-03-2012, 09:11 PM
Thanks Erik that's what I will do when the Mrs gets home and kiddies go to bed

MaxHeadRoom
05-03-2012, 10:20 PM
Is the 200v 10a rectifier suggested by Granite? To my mind that would prevent any regen voltage being absorbed by the power supply Caps?
I have never seen this done before and I have installed many servo systems over the years?
Max.

legendboy
05-03-2012, 11:50 PM
Yes it is suggested by GD. I asked mike from dashx if it was required and he said no however he did tell me he uses bridge rectifiers instead. I did buy one but I don't know how to install it.

Should I?

I found a chip stuck in between the board and motor phase c hv+ pin. It could have been touching 2 pins but I could barely see it. Took me a couple minutes and multiple tools to get it out.

All 3 drives are working fine but tuning is a bitch. I feel like I am right back to where I started when I first tuned these servos several months ago. My memory is bad these days.

Even mike from dashx (bought drives from http://dashx.net ) could not get these motors tuned. I spent hours at his house trying. Several emails back and forth between tero @ granite and nothing.

What happened was in picked up some key bits of missing info from Mike and was able to get a tune working in 10 mins on my own. For the life of me I can't remember what they were....

legendboy
05-03-2012, 11:58 PM
I would love some tuning help if anyone wants to get into it with me. I would be eternally greatful lol

macona
05-04-2012, 03:36 AM
Thinking about it, I suppose it could be any of the drives shorting out since they are all wired together and share a common regenerative energy resistor.....

That is a no-no. Look at your wiring diagram. Specifically says "Do not share single braking resistor between multiple drives".

legendboy
05-04-2012, 10:24 AM
I believe what that comment refers to would be tying the A0 pins on each drive to a common resistor.

It is acceptable to have drives wired such that only one drive has the resistor connected per HV bus. I have had this confirmed by granite

MaxHeadRoom
05-04-2012, 10:31 AM
Yes it is suggested by GD. I asked mike from dashx if it was required and he said no however he did tell me he uses bridge rectifiers instead. I did buy one but I don't know how to install it.

Should I?

...

IMO it is serving no purpose and in fact detrimental, as also I believe that switching supplies have no place for stepper or servo supplies, that is maybe why they suggested it? With a linear supply, which BTW is far more rugged, the capacitors present a very low impedance to any reverse EMF, which would be defeated if a rectifier were used in series.
Also I find it strange that the resistor is termed a 'braking' resistor, normally the resistor is switched across the P.S. bus in a servo system, the drive should be under the control of the PID loop and should not require any braking resistor placed across a motor as in a non-servo drive?
Max.

legendboy
05-04-2012, 11:27 AM
IMO it is serving no purpose and in fact detrimental, as also I believe that switching supplies have no place for stepper or servo supplies, that is maybe why they suggested it? With a linear supply, which BTW is far more rugged, the capacitors present a very low impedance to any reverse EMF, which would be defeated if a rectifier were used in series.
Also I find it strange that the resistor is termed a 'braking' resistor, normally the resistor is switched across the P.S. bus in a servo system, the drive should be under the control of the PID loop and should not require any braking resistor placed across a motor as in a non-servo drive?
Max.

Well if the consensus here is I should be using a toridial linear power supply i will change it, i was just going along with what GD suggested and sold as a package. I do remember you commenting on this before...

The regenerative energy resistor is tied to HV -0 and the A0 pin. As far as I understand the drive sends excess regenerative energy thru this pin to the resistor. This is basically the extent of my knowledge on the subject. I understand why the resistor is needed, how it works and thats about it

legendboy
05-04-2012, 11:40 AM
Here is the response from GD from the initial message i sent, before finding the chip

"Can you tell what was the value of HV upper limit parameter in GDtool and your power supply voltage during this incident?

If upper voltage limit is about same than the PSU voltage, then VSD continuously drives current to brake resistor to try reduce voltage causing the resistor burn"

MaxHeadRoom
05-04-2012, 11:40 AM
At this stage you could carry on with the switcher, but they are a bear to fix if it should die on you.
The toroidal has been my choice for some time, apart from the advantage of a rugged linear, they are a cinch to modify a secondary or add an over-wind, and IF they should fail, a cinch to fix.:cool:
Max.

MaxHeadRoom
05-04-2012, 11:42 AM
If upper voltage limit is about same than the PSU voltage, then VSD continuously drives current to brake resistor to try reduce voltage causing the resistor burn"

That confirms what I suspected in a previous post, it is not truly a brake resistor but a dump for the P.S. bus.
The linear supply without the series diode does this automatically to a degree.
Max.

legendboy
05-04-2012, 12:41 PM
Gotcha

Well i will continue with what i have for the time being

Granite also recommends a 200v 330uf cap between hv+ and ground at the drive if power cables exceed 30cm. I bought the caps but have not installed them. The wiring is likely close to 1m, 12ga.

I also ran thru resistor sizing in the manual, i should likely be using a 100w/150ohm, i was given 50w/150ohm by dashx

MaxHeadRoom
05-04-2012, 12:56 PM
I also ran thru resistor sizing in the manual, i should likely be using a 100w/150ohm, i was given 50w/150ohm by dashx

Although if this is only conducting momentarily when the motor back EMF causes the bus to rise then you may not need higher wattage, if the Bus voltage is at such a value that causes the dump circuit to be conducting almost continuously then it's another matter, but this of itself is another problem, i.e. P.S. exceeds drive rating?
Max.

Erik Brewster
05-04-2012, 01:18 PM
I would love some tuning help if anyone wants to get into it with me. I would be eternally greatful lol
I can help. I looked at the tuning support on their site and I think I understand it pretty well.

legendboy
05-04-2012, 05:14 PM
Here is the tuning manual here (http://www.telusplanet.net/public/shackner/R2E3/Servo%20tuning/Tuning_manual.pdf)

and the drive manual here (http://www.telusplanet.net/public/shackner/R2E3/Servo%20tuning/vsd-e_160_manual.pdf)

i was also using this as a reference however i will need to study it again

http://support.motioneng.com/Downloads-Notes/Tuning/default.htm

and here is the term cross reference for the above link and GDtool

http://www.telusplanet.net/public/shackner/R2E3/Servo%20tuning/tuningCrossRef.jpg

legendboy
05-04-2012, 05:26 PM
I can get my torque tuning looking like this very easily however once i switch to velocity or position mode, things start to fall apart.

Seems as i am having trouble getting the motor to respond to the response tests

http://www.telusplanet.net/public/shackner/R2E3/Servo%20tuning/torque%20Capture.JPG

i am pretty sure i used PID instead of PIV tuning position mode when i bench tuned each drive before

Erik Brewster
05-04-2012, 05:56 PM
OK. This looks like you have about 1 kHz of current loop bandwidth. It's just a touch underdamped, but it looks fine.

I would use PIV if I were you. It's not a big difference between PIV and PID in performance, but the PID block diagram isn't listed in the product manual, which doesn't give me warm fuzzies about it.

When you go to PIV, you say things fall apart.
- Are you staring with zero values for all your tuning values? Start with a high frequency for the torque low pass (1000 Hz?)
- I would then start by setting velocity feedforward to 100% (I am guessing on the units here, what are the velocity feedforward units?)
- Then start with a small value for velocity p and try to make the response nice, like in the tuning manual (or like your current loop plots).
-- Make some moves back and forth that are representative of a fast move (you can start with slow moves until you get some confidence).
-- Keep turning velocity p up until something bad happens, moving to make sure things are ok between any changes in a tuning parameter. Something bad could be noise you don't like, or it could be motor oscillation, or it could be overshooting in the motion.
--- If you find some limit in velocity p that is not noisiness, turn down velocity p by 50% (this will be to leave some stability margin)
--- When you get to a limit on velocity p, if it is too noisy, turn down the torque low pass frequency until you either see noise reduce to an acceptable level or you get worse behavior.
--- If you turned down the torque low pass filter, then go back and do the adjustment of velocity p, starting with the value you left off with. Once you finish this velocity p / torque low pass iteration phase, turn down velocity p by 50%, if you haven't already.

Send in some picture of your success or failure at this point. I think going further than this would be too much for one post. I find most people have all the tuning reference they need (the motioneng.com one is very good), but most people feel like they are drinking from a fire hose, and that is the biggest problem.

Erik Brewster
05-04-2012, 05:58 PM
Seems as i am having trouble getting the motor to respond to the response tests

Can you elaborate on this? Do you mean it doesn't move? Something else?

legendboy
05-04-2012, 08:56 PM
Can you elaborate on this? Do you mean it doesn't move? Something else?

Let's just ignore my comment until after I report back later tonight

I just read this as well, fairly basic but better explanation then the GD manual

Http://www.compumotor.com/whitepages/ServoFundamentals.pdf

legendboy
05-04-2012, 09:09 PM
I also got a copy of my cmc servo spec sheet here (http://www.telusplanet.net/public/shackner/R2E3/retorfit/C400R400F560.pdf)

(C402-3 winding)

not sure if that helps

legendboy
05-04-2012, 10:56 PM
I know this is probably a pita but it might be helpful to install gdtool, its a 10mb download (http://www.granitedevices.fi/assets/files/GDtool251.exe)

Filled in some comments in red


OK. This looks like you have about 1 kHz of current loop bandwidth. It's just a touch underdamped, but it looks fine.

I would use PIV if I were you. It's not a big difference between PIV and PID in performance, but the PID block diagram isn't listed in the product manual, which doesn't give me warm fuzzies about it.

dualdc mode is tuned using pid. it is in that manual but not in the gdtool manual

When you go to PIV, you say things fall apart.
- Are you staring with zero values for all your tuning values? Start with a high frequency for the torque low pass (1000 Hz?)

I did start with all zero values and used 1000Hz low pass. (Tuning torque the manual says to use 3300Kz and then turn down to 330Kz after tuning is done)

- I would then start by setting velocity feedforward to 100% (I am guessing on the units here, what are the velocity feedforward units?)

I have no idea what the units are. The max unit value is 32767 for that field

- Then start with a small value for velocity p and try to make the response nice, like in the tuning manual (or like your current loop plots).

Not going to happen without fixing some other settings

-- Make some moves back and forth that are representative of a fast move (you can start with slow moves until you get some confidence).


-- Keep turning velocity p up until something bad happens, moving to make sure things are ok between any changes in a tuning parameter. Something bad could be noise you don't like, or it could be motor oscillation, or it could be overshooting in the motion.

I can get to around 3800 p and then i start getting over current faults, graph does not improve at all

--- If you find some limit in velocity p that is not noisiness, turn down velocity p by 50% (this will be to leave some stability margin)
--- When you get to a limit on velocity p, if it is too noisy, turn down the torque low pass frequency until you either see noise reduce to an acceptable level or you get worse behavior.
--- If you turned down the torque low pass filter, then go back and do the adjustment of velocity p, starting with the value you left off with. Once you finish this velocity p / torque low pass iteration phase, turn down velocity p by 50%, if you haven't already.

Send in some picture of your success or failure at this point. I think going further than this would be too much for one post. I find most people have all the tuning reference they need (the motioneng.com one is very good), but most people feel like they are drinking from a fire hose, and that is the biggest problem.

Here is a typical position mode step response test plot

http://www.telusplanet.net/public/shackner/R2E3/Servo%20tuning/position%20response%20bad.JPG

Position response tabs

http://www.telusplanet.net/public/shackner/R2E3/Servo%20tuning/step%20response.JPG

Step response amplitude. When you mouse over the field this is what it says:

This adjusts how large step response travel/velocity/amplitude will be commanded to drive during testing.

-In position mode this equals position travel distance (input scaling has effect on actual step amplitude)
-In velocity mode this equals target velocity value (input scaling has effect on actual target speed)
-In torque mode this equals current value in milliamperes (scaling has no effect)


http://www.telusplanet.net/public/shackner/R2E3/Servo%20tuning/step%20response%20settings.JPG

legendboy
05-04-2012, 10:58 PM
I do not know how to calculate what the trajectory planner values should be

http://www.telusplanet.net/public/shackner/R2E3/Servo%20tuning/trajectory%20planner.JPG


The tuning I am doing now is with the belt off the z axis servo, so motor only

Erik Brewster
05-05-2012, 12:41 AM
I do not know how to calculate what the trajectory planner values should be

Sounds like you need to understand your units first. Is there a screen that tells you the actual encoder position? Look there and see what the units are. Then move the motor by hand one revolution and make sure the that tuning program agrees that you moved it that far. If not, then you need to figure out what needs to change in the scaling for the encoder / units.

I think a generic tuning move would be something like:
600 rpm (10 rps) max speed
6000 rpm (100 rps^2) max accel
2 rev position distance

It didn't look like you picked a move distance from your pictures. If you pick a move isn't useful for your tuning, you aren't going to get very far with tuning.

Erik Brewster
05-05-2012, 12:55 AM
http://www.telusplanet.net/public/shackner/R2E3/Servo%20tuning/step%20response%20settings.JPG

I think you should check the torque target vale and val P controller output check boxes. It would be helpful if you could see if there is any torque applied to the motor. Also, please let us know what you are seeing and hearing. Was there any visible movement or noise from the motor? Until we get things moving, we will need all the info we can get.

legendboy
05-10-2012, 01:48 PM
Probably start back on this tomorrow, want to finish getting the rusnok cleaned up and ready as I have some milling work to do on the weekend.


Fiddling around with GDtool at work I am pretty sure my trajectory planner settings are way off

If i decide I want to have 275ipm max velocity

275ipm = 6984mm/min

6984 / (1/2 * 5) = 2793.6 rpm
(1/2 is pulley ratio)

Velocity limit set at 3730 gives:

Effective velocity limit 2797.5 rpm
Effective acceleration limit 31.2 rps^2
Acceleration time to full speed 1.492 seconds

I think* these sound like resonable numbers and my math is right :D


I have asked Tero to explain how to apply feedforwards units. Hopefully he answers me by the weekend

Erik Brewster
05-10-2012, 02:03 PM
For tuning, you probably want, shorter faster moves, with higher acceleration. Tuning is a time for two things:
- Determine/optimize the performance of the system.
- Make sure it is stable in the face of disturbances. Small, fast moves tend to perturb systems better.

There is no reason why you need to have only one move for tuning. You can do a longer one, if you want. Then, when you are happy, make a small, fast one, just to make sure things are stable.

legendboy
05-10-2012, 03:25 PM
Alright to make longer moves as per Tero:

-Increasing "mutliplier" parameter in trajectory planner page
-Reduce "sample rate" in step test page
-Increase "buffer length" in step test page

I am going to assume to make short moves will be the opposite

As for fast, I think that is "step response amplitude"

legendboy
05-23-2012, 12:22 AM
I have discovered that my z axis encoder is not functioning properly.

I will check the wiring again tomorrow but I am thinking it may be damaged because of the short it had developed.

It works for part of a rotation then stops counting then starts again. Will not hold a zero position...etc

The other 2 encoders work fine

Erik Brewster
05-23-2012, 01:00 AM
That doesn't sound like damage from a short. That sounds like the encoder disk is either dirty or out of alignment. It isn't impossible for an encoder to die in a "sorta working" state, but it doesn't happen a lot. A wobbly, but functional encoder disk that is at the end of the tolerance on axial alignment would do exactly what you describe. The encoder disk / readhead distance is usually pretty critical. Make sure it is right. And also make sure that your motor is not moving in and out as it rotates from some strange mechanical problem. That is bad, too.

macona
05-23-2012, 03:43 AM
I agree, there is crud on the encoder disc.

legendboy
05-23-2012, 10:29 AM
ah ok thanks for the info. hopefully this is something i can rectify on my own, with your help :)

MaxHeadRoom
05-23-2012, 05:18 PM
IF you need to clean the disc, it can sometimes be done using denatured alcohol and either lint free cloth or a Q tip as a last resort.
Max.

macona
05-23-2012, 11:07 PM
Heidenhain recommends Windex. Serious..

legendboy
05-24-2012, 01:33 AM
Had some good success tonight. Found another broken wire coming from one of the receiving leds. Soldier it back to the board, gave the whole thing a blast of aerosol isopropyl alcohol and a good blast of compressed air and good as new.

I was easily able to tune the servo after fixing it. (belt off)

I'll post some screen shots and settings in the morning

Erik Brewster
05-24-2012, 03:07 AM
Heidenhain recommends Windex. Serious..

Do you have any links to reference this? It makes sense, but I've got a several expensive Heidenhain linear encoders in a test setup that could use some cleaning by a crew of inexperienced people. I would love to have a simple, factory endorsed procedure.

I did a search and found this, which is pretty close, but I was hoping that you knew of something straight from the horse's mouth.

http://www.practicalmachinist.com/vb/deckel-maho-aciera-abene-mills/cleaning-heidenhain-scale-how-earth-do-you-get-there-109202/#post379226

macona
05-24-2012, 03:46 AM
I had gotten the same info from Anilam who is owned by Heidenhain now. Scales are really resilient. You have to really mess one up to make it not read, especially the real heidenhain ones with analog scales. They can see around dirt and scratches.

legendboy
05-24-2012, 10:19 AM
I forgot my flash drive at home so no pics

Basically I setup GDTool to make long hard fast moves, 3, 2 direction changes, over the course of 2 seconds.
Tuned it that way and then changed the settings to make the same move at about half the commanded distance of the first test in less then half the time (.8s)

The step position graph had some overshoot with the shorter move and i was able to adjust piv to minimize that.

I will spend some time tonight getting the appropriate screen shots so you guys can see how the traces look

Pretty happy to have solved this problem, i see my machine being under usbcnc control by the weekend if all goes well

legendboy
05-24-2012, 01:42 PM
Quick question:

Should I temporarly re wire my estop and home switches to cut power to the main contactor while tuning servos mechanically connected to the machine? I have 3 solid state contactors i might be able to temp wire something up? although estop is NC and home is NO

The granite drives don't have an estop circuit input

I didn't have any runaway problems last night but i have had this happen in past tuning sessions when "pushing the envelope"

MaxHeadRoom
05-24-2012, 02:55 PM
The granite drives don't have an estop circuit input



AFAIK they have an ENABLE input, Turns off the outputs, you could wire up for a temporary stop?
Max.

legendboy
05-24-2012, 03:19 PM
Looking at the user configurable inputs there is a disable in

"If this input has logic value 1, drive will disable motor control and let motor
free-wheel."

Would it be as simple as wiring up a NO switch to +5v i can keep in my hand in case of runaway?

MaxHeadRoom
05-24-2012, 03:34 PM
It would seem that it is active high, usually the enable is taken to common, if all else fails, try both ways, it should not hurt.
Some of these manuals are not that good in describing the actual nature of the input in order to make an informed decision. :confused:
Max.

legendboy
05-24-2012, 03:43 PM
It would seem that it is active high, usually the enable is taken to common, if all else fails, try both ways, it should not hurt.
Some of these manuals are not that good in describing the actual nature of the input in order to make an informed decision. :confused:
Max.

I agree, the granite manual is bad for that.

The usbcnc manual shows in detail how the inputs and outputs work, if they are pull up, pull down open collector, schmatics showing the correct way to wire different types of peripherals...etc.

legendboy
05-24-2012, 11:49 PM
This is going to be pic heavy so i am going to post links instead of pictures
The following are my Z axis servo mechanically connected to the machine

Trajectory planner settings:
Effective velocity limit 2500.5rpm
Effective acceleration limit 125rps^2
Acceleration time to full speed 0.3334s

I have no idea if these acceleration figures are realistic, any guidance is appreciated

Torque settings:
P gain 1300
I gain 150
low pass 3300Hz

Capture settings: (these make my traces look like the ones in the GDtool manual)
Buffer length 1000 samples
Sample rate 20000
Step response amplitude 30%

Torque trace (http://www.telusplanet.net/public/shackner/R2E3/Servo%20tuning/1/torque%20trace.JPG)

This looks exactly the way the manual says it is suppose to look

On to position traces...

Capture settings:
Buffer length 2000 samples
Sample rate 1250
Step response amplitude 1000 units

The following were tested at 5000 vel ff except for the last one. Torque low pass set at 330Hz as per the manual

I am posting all these so you can see what I have to work with. Doesn't really matter what I change the traces are hard to compare against the GDtool manual example traces (oscillation?, lack of damping? encoder res?)

I saved the trace file, brought into the house and used snipping tool to make the jpegs. The "Steps|mA" axis figures need to be x1000. Looks like a software bug.

Velocity P gain 500 (http://www.telusplanet.net/public/shackner/R2E3/Servo%20tuning/1/500.JPG)

Velocity P gain 1500 (http://www.telusplanet.net/public/shackner/R2E3/Servo%20tuning/1/1500.JPG)

Velocity P gain 2500 (http://www.telusplanet.net/public/shackner/R2E3/Servo%20tuning/1/2500.JPG)

Velocity P gain 3500 (http://www.telusplanet.net/public/shackner/R2E3/Servo%20tuning/1/3500.JPG)

Velocity P gain 4500 (http://www.telusplanet.net/public/shackner/R2E3/Servo%20tuning/1/4500.JPG)

Velocity P gain 5500 (http://www.telusplanet.net/public/shackner/R2E3/Servo%20tuning/1/5500.JPG)

Velocity P gain 6500 (http://www.telusplanet.net/public/shackner/R2E3/Servo%20tuning/1/6500.JPG)

Velocity P gain 7500 (http://www.telusplanet.net/public/shackner/R2E3/Servo%20tuning/1/7500.JPG)

Velocity P gain 8500 (http://www.telusplanet.net/public/shackner/R2E3/Servo%20tuning/1/8500.JPG)

Velocity P gain 8500 vel ff 15000 (http://www.telusplanet.net/public/shackner/R2E3/Servo%20tuning/1/8500%20ff15000.JPG)

legendboy
05-25-2012, 11:03 AM
Here is Tero's response to my question:

"Tero, what units are vel and accel feedforwards in? How can this be determined? Trial and error only?"


"About feedforward value tuning:
1. set accel and velocity FF's to zero and do a step response test (just as reference)
2. start increasing velocity FF until you find best value (produces smallest follwing error)
3. keep the optimal velocity FF value and start increasing acceleration FF value until you find best value (produces smallest follwing error)
4. done!"



I have my mother n law comming to watch the kids all day tomorrow and I am hoping to be able to button this thing up

legendboy
05-25-2012, 07:01 PM
I just realized I have my trajectory planner settings completely wrong for z axis :o

legendboy
05-27-2012, 11:41 PM
Well I can home the machine but jogging can fault out the drives

The error is "due to bad tuning" :D

Erik Brewster
05-28-2012, 03:16 PM
A few comments:

You don't mention your impressions of the motion. Is it noisy? Quiet? Anything strange happening? Do you think you are actually getting to 2500 RPM? If so, the resolution of the plot is completely unacceptable, and you should be pushing back on your Granite to get you a better plot.

Another way to deal with the noise issue with low resolution encoders is to look at the position error, commanded torque, and commanded velocity. Can you do this in their scope? The position plots do not suffer quantization noise nearly as bad as the velocity plots. Can you plot these three all at once? If you can only do two, position error and commanded velocity are enough.

What's with all the spikes in the actual velocity? At 0.575 s in the 2500.jpg picture, for example. Is this your flaky encoder? It doesn't look like a normal tuning artifact. It could be a backlash thing, but it doesn't really look like it.

It seems like some of your pictures are mislabeled. Your p=1500 and p=3500 pictures look like good, fast response, but your p = 2500 does not. There is nothing wrong with p = 2500 being slow, in itself, but both a lower and higher gain having significantly high performance in such a simple system is fishy.

legendboy
05-28-2012, 04:17 PM
A few comments:

You don't mention your impressions of the motion. Is it noisy? Quiet? Anything strange happening? Do you think you are actually getting to 2500 RPM? If so, the resolution of the plot is completely unacceptable, and you should be pushing back on your Granite to get you a better plot.

Another way to deal with the noise issue with low resolution encoders is to look at the position error, commanded torque, and commanded velocity. Can you do this in their scope? The position plots do not suffer quantization noise nearly as bad as the velocity plots. Can you plot these three all at once? If you can only do two, position error and commanded velocity are enough.

What's with all the spikes in the actual velocity? At 0.575 s in the 2500.jpg picture, for example. Is this your flaky encoder? It doesn't look like a normal tuning artifact. It could be a backlash thing, but it doesn't really look like it.

It seems like some of your pictures are mislabeled. Your p=1500 and p=3500 pictures look like good, fast response, but your p = 2500 does not. There is nothing wrong with p = 2500 being slow, in itself, but both a lower and higher gain having significantly high performance in such a simple system is fishy.

Thanks for the reply Erik
While running those step response tests the motors sounded ok, a bit of dithering. I didnít notice anything strange.
No way I was hitting 2500rpm

I can run step response with position error, commanded tq and commanded vel. Will try that tonight.

I am not sure what that is or what causes it. These graphs are pretty typical of all 3 axis.
I will double check on the file names tonight but I was pretty careful when I named them. I have no idea other then that.

Erik Brewster
05-28-2012, 06:22 PM
If you run a larger step, then you will see the motion more clearly. The velocity resolution is the same, no matter the amplitude of the velocity step, so the larger the step, the less you notice the resolution limitation.

Also, tuning is the right time to make all sorts of moves and deal with the problems. You don't want to discover this stuff when you are cutting metal.


When you plot position error, torque command and velocity command, you can use the three traces in this manner:
- Velocity command. This will show you where you are in the move (acceleration, constant velocity, etc.)
- Position error. You will see any oscillations clearly here. This is where you will likely focus
- Torque command. You will see velocity loop position oscillations here first, before they are obvious in the position error. You will also see noise problems here. Consider this one optional, if you are pressed for data recording resources and must eliminate a trace.

I wouldn't worry too much about that oddball trace, but thought I would mention it. I look for consistant, even changes and results as a sign of a healthy system, so things like that stick out to me.

legendboy
05-28-2012, 10:40 PM
Erik, is following error the same thing as position error?

Erik Brewster
05-28-2012, 11:35 PM
Yep, same thing.

legendboy
05-29-2012, 01:53 AM
After I posted that question I kept testing different things

I cranked up my acceleration limit to 112.5rps^2 and that seemed to make a big difference (i have no idea what this should be for my machine)


P2000 (http://www.telusplanet.net/public/shackner/R2E3/Servo%20tuning/Tuning%202/P2000.JPG)

P3000 (http://www.telusplanet.net/public/shackner/R2E3/Servo%20tuning/Tuning%202/P3000.JPG)

P4000 (http://www.telusplanet.net/public/shackner/R2E3/Servo%20tuning/Tuning%202/P4000.JPG)

P5000 (http://www.telusplanet.net/public/shackner/R2E3/Servo%20tuning/Tuning%202/P5000.JPG)

P6000 (http://www.telusplanet.net/public/shackner/R2E3/Servo%20tuning/Tuning%202/P6000.JPG)

P7000 (http://www.telusplanet.net/public/shackner/R2E3/Servo%20tuning/Tuning%202/P7000.JPG)

P8000 and bad noise (http://www.telusplanet.net/public/shackner/R2E3/Servo%20tuning/Tuning%202/P8000%20noise.JPG)

figured i would keep going at P7000 and started adding I gain here

P7000i10 (http://www.telusplanet.net/public/shackner/R2E3/Servo%20tuning/Tuning%202/P7000i10.JPG)

P7000i20 (http://www.telusplanet.net/public/shackner/R2E3/Servo%20tuning/Tuning%202/P7000i20.JPG)

P7000i30 (http://www.telusplanet.net/public/shackner/R2E3/Servo%20tuning/Tuning%202/P7000i30.JPG)

P7000i40 (http://www.telusplanet.net/public/shackner/R2E3/Servo%20tuning/Tuning%202/P7000i40.JPG)

P7000i50 (http://www.telusplanet.net/public/shackner/R2E3/Servo%20tuning/Tuning%202/P7000i50.JPG)

P7000i60 (http://www.telusplanet.net/public/shackner/R2E3/Servo%20tuning/Tuning%202/P7000i60.JPG)

P7000i70 (http://www.telusplanet.net/public/shackner/R2E3/Servo%20tuning/Tuning%202/P7000i70.JPG)

P7000i80 (http://www.telusplanet.net/public/shackner/R2E3/Servo%20tuning/Tuning%202/P7000i80.JPG)

P7000i90 (http://www.telusplanet.net/public/shackner/R2E3/Servo%20tuning/Tuning%202/P7000i90.JPG)

P7000i100 (http://www.telusplanet.net/public/shackner/R2E3/Servo%20tuning/Tuning%202/P7000i100.JPG)

P7000i110 (http://www.telusplanet.net/public/shackner/R2E3/Servo%20tuning/Tuning%202/P7000i110.JPG)

P7000i120 (http://www.telusplanet.net/public/shackner/R2E3/Servo%20tuning/Tuning%202/P7000i120.JPG)

figured i would roll with Vel. I gain 50 and continue on to position

this is position baseline

P7000i50p0 (http://www.telusplanet.net/public/shackner/R2E3/Servo%20tuning/Tuning%202/P7000i50p0.JPG)

i had to lower HV Bus lower limit here as any position gain was giving me under voltage faults

P7000i50p80 (http://www.telusplanet.net/public/shackner/R2E3/Servo%20tuning/Tuning%202/P7000i50p80.JPG)

i stopped adding position gain at 240. I had more traces to show but for some reason the files i put of my flash drive were showing velocity instead of position (except the 2 above)

My usbcnc vel. and accel. settings are still not correct and or the servo drive settings as a g0f50x1 still gave me an overcurrent/undercurrent drive fault but am i headed in the right general direction to getting it tuned?

Here is a video showing the machine move/sound at the end. I have no idea if this is a fast, slow or medium move! This is typical of all traces above (x & y)

http://www.youtube.com/watch?v=3oYiinhOxTc&feature=youtu.be

Here is a video showing homing with usbcnc

http://www.youtube.com/watch?v=tqgPWDPEyJs&feature=youtu.be

macona
05-29-2012, 06:24 AM
Looks good. Normally the acceleration settings in the drive itself are set to the maximum you can do without going over current. Then final acceleration settings are set in the control software.

legendboy
05-29-2012, 10:22 AM
Looks good. Normally the acceleration settings in the drive itself are set to the maximum you can do without going over current. Then final acceleration settings are set in the control software.

That makes sense to me. Its gonna be a long day at work today

legendboy
05-29-2012, 03:00 PM
Had to go home at lunch and play with it :p

I set Vel. in/S to 4.1 and Acc. in/S^2 to 5 in my controller and made a huge difference.

I can rapid 250ipm no problem however rapid linear xy move threw OC fault.
Was able to g1f150 xy no problem so I think I may be at the point of fine tuning!

I asked Eding about Vel. and Accel. settings months ago:

"These are generally tuned by trial and error?
Any guidance appreciated"

his reply

"Usually Yes.
It depends on to total configuration machine (masses+frictions) + gears + drive + motor behavior what the maximum accel/vel is.
And yes, it can be calculated if you know all parameters including frictions masses and inertia's voltages and motor Kt (Current->torque factor).
Also it depends on personal favor, what is more important for you acceleration or velocity, you may give in at max velocity and get higher acceleration.
A decent tuned machine has an acceleration which is a factor 3-10 higher as the velocity to give you a rule of thumb.
If you are going to do a lot of 3D milling, you need an acceleration as high as possible to get short milling times.

Regards,
Bert"

macona
05-30-2012, 05:40 AM
I wonder why these guys have not come up with an auto tune routine yet. Wonder if there is a liability issue.

The name brand drives I use, A-B, Elmo, Mitsu, Yaskawa all have auto tune to one degree or another. The AB and Elmos have a thing where the drive moves the motor and the control figures the tuning. The Elmo one is really comprehensive. The yaskawa and mitsubishi auto tunes are a little different since they are set for specific motors. But the newer drives will auto tune on the fly to compensate for different loads. Once my drive learned my lathe it has been rock solid.

legendboy
05-30-2012, 10:18 AM
In retrospect I should have bought a motor drive combo like Mcgyver did, with autotune.

I have spent so much time sitting in front of my laptop trying to figure this out I feel like I am pretty much at the end of my rope.

Tonight I am going to start over and follow Erik's tuning suggestions as closely as my understanding allows me too


OK. This looks like you have about 1 kHz of current loop bandwidth. It's just a touch underdamped, but it looks fine.

I would use PIV if I were you. It's not a big difference between PIV and PID in performance, but the PID block diagram isn't listed in the product manual, which doesn't give me warm fuzzies about it.

When you go to PIV, you say things fall apart.
- Are you staring with zero values for all your tuning values? Start with a high frequency for the torque low pass (1000 Hz?)
- I would then start by setting velocity feedforward to 100% (I am guessing on the units here, what are the velocity feedforward units?)
- Then start with a small value for velocity p and try to make the response nice, like in the tuning manual (or like your current loop plots).
-- Make some moves back and forth that are representative of a fast move (you can start with slow moves until you get some confidence).
-- Keep turning velocity p up until something bad happens, moving to make sure things are ok between any changes in a tuning parameter. Something bad could be noise you don't like, or it could be motor oscillation, or it could be overshooting in the motion.
--- If you find some limit in velocity p that is not noisiness, turn down velocity p by 50% (this will be to leave some stability margin)
--- When you get to a limit on velocity p, if it is too noisy, turn down the torque low pass frequency until you either see noise reduce to an acceptable level or you get worse behavior.
--- If you turned down the torque low pass filter, then go back and do the adjustment of velocity p, starting with the value you left off with. Once you finish this velocity p / torque low pass iteration phase, turn down velocity p by 50%, if you haven't already.

Send in some picture of your success or failure at this point. I think going further than this would be too much for one post. I find most people have all the tuning reference they need (the motioneng.com one is very good), but most people feel like they are drinking from a fire hose, and that is the biggest problem.

Sounds like you need to understand your units first. Is there a screen that tells you the actual encoder position? Look there and see what the units are. Then move the motor by hand one revolution and make sure the that tuning program agrees that you moved it that far. If not, then you need to figure out what needs to change in the scaling for the encoder / units.

I think a generic tuning move would be something like:
600 rpm (10 rps) max speed
6000 rpm (100 rps^2) max accel
2 rev position distance

It didn't look like you picked a move distance from your pictures. If you pick a move isn't useful for your tuning, you aren't going to get very far with tuning.


I think you should check the torque target vale and val P controller output check boxes. It would be helpful if you could see if there is any torque applied to the motor. Also, please let us know what you are seeing and hearing. Was there any visible movement or noise from the motor? Until we get things moving, we will need all the info we can get.


For tuning, you probably want, shorter faster moves, with higher acceleration. Tuning is a time for two things:
- Determine/optimize the performance of the system.
- Make sure it is stable in the face of disturbances. Small, fast moves tend to perturb systems better.

There is no reason why you need to have only one move for tuning. You can do a longer one, if you want. Then, when you are happy, make a small, fast one, just to make sure things are stable.

Erik Brewster
05-30-2012, 12:17 PM
I wonder why these guys have not come up with an auto tune routine yet.

A-B, Elmo, Mitsu, Yaskawa all have auto tune to one degree or another.

Autotuners are really tough to develop. All the companies you mention are long established companies with lots of experience and resources and have done a good job. Granite doesn't even write their own tuning documents, they have a link to Motion Engineering to use their tuning documentation. It's good documentation, and even applies to their product pretty closely, but it's a big indication of their controls ability.

Autotuners are only a liability if they don't work and it can't figure out that it didn't work.

legendboy
05-30-2012, 01:02 PM
Granite doesn't even write their own tuning documents, they have a link to Motion Engineering to use their tuning documentation. It's good documentation, and even applies to their product pretty closely, but it's a big indication of their controls ability.


That has been I think a big part of my frustration.

Granite has a basic tuning "manual" that shows ideal target graphs and such but nothing in the way of detailed explanations on what is happening and how it works.

I am the type of person that needs to understand how stuff works in order for it to make sense. The Motion Eng. instruction is very comprehensive albeit over my head. Its a fire hose" as Erik put it.

I didn't get that far in Math or Physics and I feel that is a handicap

legendboy
06-10-2012, 06:48 PM
It would seem that it is active high, usually the enable is taken to common, if all else fails, try both ways, it should not hurt.
Some of these manuals are not that good in describing the actual nature of the input in order to make an informed decision. :confused:
Max.

Here is a diagram of the "disable input" I am trying to get working temporarily with my estop circuit for tuning

http://www.telusplanet.net/public/shackner/R2E3/retorfit/Input.JPG

So this is telling me I need to supply +5v to the input thru a 220 ohm resistor?

MaxHeadRoom
06-10-2012, 07:05 PM
That should do it on 5v, the fact it is an Opto input you can use just about any supply option with the correct resistor.
If IO_com is not connected you have the option of using it as sink or source input.
The example shows it is a Sink input with source type supply device.
Max.

legendboy
06-10-2012, 07:11 PM
That should do it on 5v, the fact it is an Opto input you can use just about any supply option with the correct resistor.
If IO_com is not connected you have the option of using it as sink or source input.
The example shows it is a Sink input with source type supply device.
Max.

Thanks for the speedy reply Max

I had to take a bit of a break from this project but back now

My estop circuit is NC, I am hoping I can make it work. I can "invert" the input but I am not 100% sure what that does

MaxHeadRoom
06-10-2012, 08:09 PM
If you have a control relay at the end of the E-stop string with a spare N.C. contact you could feed all the drives Opto enables from this?
Max.

legendboy
06-10-2012, 10:57 PM
I don't have one. I was thinking about buying this one

http://www.ebay.com/itm/260907451525?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649

MaxHeadRoom
06-10-2012, 11:27 PM
Safety relays are nice, different models posses different features, controlled shut down timers etc.
You do not see them so much in N.A. origin equipment, they are just about mandatory in EU machinery.
Max.

legendboy
06-13-2012, 10:55 PM
Just can't seem to get the disable input to work.

I have a 24v relay powered up when my estop circuit is not activated
I have a 5vdc regulated ps connected 0v to io_com and 5v to the Opto input on the drive. Power is applied thru a 220ohm resistor to the input when the relay is turned off.

I have tried all available Opto inputs and 2 drives. Power is flowing as it should.

:confused:



http://www.telusplanet.net/public/shackner/R2E3/retorfit/Input.JPG

legendboy
06-13-2012, 11:03 PM
The two inputs I can use are called:

SPI SCLK general purpose
SPI MOSI general purpose

MaxHeadRoom
06-13-2012, 11:24 PM
According to the manual it seems that the input can be 5v direct, and only a resistor used if more than 5v supply, also it implies the 5v is required for enable, and the default is disable?
Maybe shoot an email to Granite to clarify it?
Max.

legendboy
06-13-2012, 11:33 PM
Did you get all that from the IO characteristics part of the manual?


Pic of the current mess i am in

http://www.telusplanet.net/public/shackner/R2E3/retorfit/mess.JPG

legendboy
06-13-2012, 11:46 PM
According to the manual it seems that the input can be 5v direct

When i do that, without the resistor, i loose connection to the drive.
I get an error when i try to connect to the drive in that state.

legendboy
06-13-2012, 11:56 PM
Same thing when I try it as servo ready

MaxHeadRoom
06-14-2012, 12:44 AM
Same thing when I try it as servo ready


?? The other manual on the site refers to the 5v direct input, and also the diagram in the link in the manual you are using shows the 220ohm res already internal for 5v use.
Max.

macona
06-14-2012, 12:52 AM
Sounds like you have some sort of ground loop going on. What kind of power supply are you trying to use?

legendboy
06-14-2012, 10:14 AM
^ thinking now I don't have the 5vdc power supply tied into the system ground

The 5v ps is a sola

MaxHeadRoom
06-14-2012, 11:25 AM
Tie it to IO_COM .
Max.

legendboy
06-14-2012, 12:03 PM
Will try tonight!

legendboy
06-14-2012, 03:03 PM
Went home at lunch and tried that, no difference

macona
06-14-2012, 03:41 PM
Is this the same power supply used to drive the breakout board?

Try running the optoisolator from a 6v battery and see what happens.

legendboy
06-14-2012, 04:17 PM
the power supply i am trying to use to activate the opto is a sola 12v/5v 1.2a unit. There is nothing else connected to it.

I have a cheap 12v switcher I am using to power the drive logic

I am not using a breakout board

I can definitely try that

macona
06-14-2012, 04:24 PM
Thats right, you were using a USB motion controller? Sink the 5v from there instead and see what happens. You have 500ma to play with off usb. No since adding extra supplies to the mess.

legendboy
06-14-2012, 04:36 PM
Thats right, you were using a USB motion controller? Sink the 5v from there instead and see what happens. You have 500ma to play with off usb. No since adding extra supplies to the mess.

Thats what i did when i first started to try and get this to work. That wasn't working so i moved on to a dedicated 5v ps

macona
06-14-2012, 04:51 PM
Huh. Something funny going on then. Might be a problem with the config of the drive and the input pins. I would be talking to granite.

legendboy
06-14-2012, 05:26 PM
yep i started a thread in the gd section over at the zone and pointed my support ticket to it. hopefully tero chimes in sometime soon

legendboy
06-14-2012, 10:15 PM
Try running the optoisolator from a 6v battery and see what happens.

just tried this, same result

legendboy
06-15-2012, 09:13 PM
Any off the wall ideas?

legendboy
06-15-2012, 09:21 PM
Just figured the input DOES work when the spi cable is not connected to the drive!

Could it be a laptop issue?

legendboy
06-15-2012, 09:47 PM
Just tried it from my control, same thing. Maybe usb serial cable?

legendboy
06-17-2012, 12:36 PM
So Tero replied in my thread. What I was trying to do is not possible.

That should likely be in the documentation somewhere :mad:

I need to use an analog input for what I am trying to do. I am not sure if I need to wire it differently. This is a non Opto input

Erik Brewster
06-17-2012, 06:29 PM
Make sure that your thing that is sending analog signals (I/O block) and the thing receiving it (servo drive) are on the same ground. Analog circuits are not typically tolerant of big (> a few volts) ground differentials. Also, if it is a single ended signal (not + and - signals), they are very subject to noise from non ideal grounds.

legendboy
06-17-2012, 11:58 PM
Thanks Erik. I got the estop working now so back to tuning!

I think i need to start with torque. I thought i had it tuned ok but i was getting tons of overcurrent faults in position mode.

How much should the x axis move during these tests? Does it even matter?

Erik Brewster
06-18-2012, 02:20 AM
One thing people worry about too much is current loop bandwidth. If you are putting a 330 Hz low pass (from memory, I might be off), then you don't really need a screaming fast current loop, as the low pass will have way more delay.

So, feel free to back off a bit on the integral term (or proportional term, too) in the current loop.

As far as move sizes, there are two kinds, in my book. Small moves because you are still afraid of your system. These should be way bigger than your backlash and other bad parts of your mechanics (hopefully just 0.001" or so), so maybe 0.1". This will allow you to not be quite as scared as the big moves. Also, make sure to make some high acceleration moves, even at these small distances. Tuning is the time you want to discover and get rid of any instability, not during machining! The small, fast moves are one kind of challenge.

Then also make some big moves -- long enough to get to max velocity for a bit. This will find the other kind of challenge -- high speeds and pushing the power limits. If everything is good, this will be very boring and just work, as all motion in a CNC should be.

I think you should do both kinds of moves. Don't be afraid to start slow and work your way up.

Over current faults could be from two areas. It depends on the drive:
* If the current loop tuning is bad, then you can get faults from over current, even if you don't ask for that much current. The solution to this is to re-tune, likely with a more underdamped current loop
* If you try to accelerate too fast, then you can get an over current fault, if the drive isn't smart enough to protect you from yourself. The solution to this is to lower your acceleration limits.

To figure out which one you have, you will want to catch the fault when it happens on a scope (virtual or real, with current probe). If you can't you can always try lowering the gains in the current loop to see if it goes away. If it does, then it likely is just current loop tuning.

macona
06-18-2012, 04:02 AM
I agree, lower your acceleration limits. Probably won't take much.

A good test of the servos and getting them to fault is running the roadrunner g-code example in mach. Lots of short moves that can trip up a poorly tuned machine. Do kick up the feed rate.

legendboy
06-19-2012, 09:12 PM
Alright I re tuned my current loop.

Buffer length 2000 samples
Sample rate 5000Hz
Step response amplitude 60% (in torque mode this equals current value in milliamperes)

I started off with P gain 1, then 10, 100, 1000.

The step response % had the table jerking pretty hard, enough to make the whole mill quiver (not on leveling pads yet) The motion was fairly short, .1 maybe a bit more.

Once I hit P 1600 I got OC fault.

Lowered the amp.% to 50% and resumed increasing P until I hit 2000 and OC fault.

Lowered the amp.% to 40% and still got OC fault. Lowered to 30%.
Re ran the step test at 30% amp. and backed off P gain by 100's until things looked "good" (compared to tuning manual)

I started adding I gain at P 1500.
I started as small as I could after re reading motioneng. piv tuning.

Added I gain like this: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, 30, 40, 50, 60, 70 (running step response in between each change)

This is what my current trace looks like at P1500, I40, 3300Hz low pass (http://www.telusplanet.net/public/shackner/R2E3/Servo%20tuning/with%20Erik/current%20traces/30%25%20P1500%20I40%203300LP.pdf)

(I decided to export these in PDF for increased resolution)

This is the same test with the low pass set at 330Hz (http://www.telusplanet.net/public/shackner/R2E3/Servo%20tuning/with%20Erik/current%20traces/30%25%20P1500%20I40%20330LP.pdf)

I think* this is good. I had I gain into the hundreds previously. I will test again and try and make a longer faster move.

Should I run the current test with different low pass filter values? Is 330Hz where I want to leave things before I move on to position?

legendboy
06-19-2012, 10:44 PM
Running some longer tests lettings things get faster, getting nothing but under voltage faults.

Manual says: Supply voltage gone below lower voltage limit. This may be caused by an undersized power supply.

The suggested settings from GD for this ps are 160000mV upper and 100000mV lower limit. I lowered the lower to 50000mV an still getting the fault.

legendboy
06-19-2012, 10:54 PM
Regarding your guys posts about lowering my acceleration limits.

In tq mode the only thing I can change are PI gains, commanded current, sample length and sample rate. Accel and vel limits are not available until the mode is switched.

Lowering the sample rate gives a longer test duration, which gives the motor time to reach higher speeds. However I can't estimate how fast the axis is moving at a given commanded current.

It looks* not too fast :confused: