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j king
06-28-2009, 01:10 PM
Hi guys,
Back from vacation. Started to mess with the mill again.I am stumped as to why the e stop doesnt work. If I set the screen to diagnostics it shows the pin being activated when the switch is pushed so I know that it is seeing it work. If I change the active low setting it will not reset so I suppose that is set ok. Any ideas? Could it be something with the charge pump settings somewhere?
The switch is set to NC now and I open it when applied.

Thanks, Jim


PS the little steppers way plenty of enough power.Scares the jebees out of me.Slowed them to 50 now.Was up 140s! I cant handle things moving that fast. Too old for surprises. : )

j king
06-28-2009, 02:13 PM
I may have found it. Be back...............

j king
06-28-2009, 04:10 PM
No such luck...

I cant get the e stop to respond and I cant get the machine to jog off the limits. I have the auto override set but the mill wont move.

Anyone around NE Ohio? Will pay someone for all there time and expenses to help on this.

I ran a little code and everything seems to be doing what its suppose to but I have these gremlins that I cant figure out.

Evan
06-28-2009, 04:50 PM
What break out board are you using?

japcas
06-28-2009, 05:56 PM
Jim, don't give up. I am working on a small cnc project now and just finished up the wiring. Now I'm trying to get the software set up properly. I learn new stuff each time I mess with it. I did print the two manuals for mach3 and read them both. I learned a lot there. Now I'm going back through and reading the configuring sections now that the hardware is wired up.

j king
06-28-2009, 06:11 PM
When it rains it pours!
I was trying to replace my clock battery on my T 43 IBM laptop. That failed and I spent well over an hour on that task trying to find out how to do it off the web.So now I must have did something to it because I cant reply to this site now with it. I log in and still no button to click on. Dang electrical crap!


Ok Rant off.

I did more checking and I may have kinda found part or the cause of my problem with Mach project. I dont have 5 vdc going to any of the limits or e stop. It goes to the BOB but doesnt come out anywhere.

j king
06-28-2009, 06:21 PM
Evan. This is it,,,,,,,,http://cnc4pc.com/Tech_Docs/C11GR7_1_User_Manual.pdf

John Stevenson
06-28-2009, 06:27 PM
Jim,
I gave you a wiring diagram of the C11G board with limits and e-stop wired including the 5v supply for the switches.

Over 360 units have been wired up this way and work.

Why don't you follow that ?

.

j king
06-28-2009, 06:36 PM
John.
I did everthing you told me to. It is still wired that way. I cant see where I messed up! It looks ok to me anyway. : )

There is no power at the terminals. does it matter which terminals on the end that takes the 5vdc inputs? I think I put them in the exact place you had sketched.It has 4 or 5 marked 5vdc on the terminal strip. I will take some pics. I probably did a stupid thing. be back.......

j king
06-28-2009, 07:15 PM
first pic is the 5 vdc end.http://img.photobucket.com/albums/v24/ikimjing/cncpics002.jpg

http://img.photobucket.com/albums/v24/ikimjing/cncpics003.jpg


http://img.photobucket.com/albums/v24/ikimjing/cncpics001.jpg

j king
06-28-2009, 07:21 PM
Hope pics arent too big.

John, the "en" jumper is the orange that is tied to the last terminal on the top. The wire that has the yellow tape around it. I had to solder these because 2 wires wouldnt fit into the strip.

The 5vd c wires are the black and blue attached where I believe they were to go. The schematic you sent showed more terminals on the low voltage end.
I believe the little jumpers are where they need to be.Lower one above the en terminal is on 2-3 and center is same.


This doesnt help I dont think but it shows the dc supply and terminal strip and fuse.http://img.photobucket.com/albums/v24/ikimjing/cncpics006.jpg

Evan
06-28-2009, 07:33 PM
I have marked with an arrow an orange wire at bottom left. What is it connected to? What signal is it carrying?

http://ixian.ca/pics6/bob1.jpg

j king
06-28-2009, 07:33 PM
I also have mach setting for input pins for the charge pump on pin 17 and set active high.

j king
06-28-2009, 07:36 PM
That is the "EN" terminal. It is connected to the pin 10 on the opposite side. It connects to the Estop terminal.

Evan
06-28-2009, 07:38 PM
Connect it to the 5v terminal directly beside it.

John Stevenson
06-28-2009, 07:42 PM
Evan.
Post #10 in this thread.

http://bbs.homeshopmachinist.net/showthread.php?t=34766

Hit the estop and it removes 5v from the enable and stops the drivers.

.

Evan
06-28-2009, 07:43 PM
It might be better to connect it to one of the 5volt power input terminals. I can't be sure that the pin beside it powered.

John Stevenson
06-28-2009, 07:43 PM
Connect it to the 5v terminal directly beside it.
If you do that it will work but the estop won't disable the drivers.

[Edit,] 5v pin beside it is powered whilst ever there is 5v on the board.

The top strip of terminals reading right to left goes 10, 5v, 11, 5v, 12,5v,13,5v,15,5v

5v goes to the estop switch which is Normally closed,NC, then back to pin 10 which is assigned in mach for E stop.
Pin 10 also goes the EN and so on to the drivers.

break the NC switch and you remove the 5v from enable

j king
06-28-2009, 07:53 PM
Ok I checked voltage on terminal 15 and its 5vdc post.It shows 5 v but non of the limit terminals or estop connections show it.?wheres it going??

Also all 4 pins on the diagnostic screen show the e stop and limit switches working. The green lights go out when switched.So I know the circuit is complete.

John Stevenson
06-28-2009, 07:58 PM
You must have 5v there because the LED's are on.

j king
06-28-2009, 08:13 PM
Johns right. My eye balls are crooked. I was probing the terminal below the 5vdc supply neg.I do have voltage. So why doesn't Mach see anything??

Evan
06-28-2009, 08:36 PM
From the BOB manual:



6.5 External Enable Pin.
The card must be provided with a 5VDC signal to enable operation. This feature
has been added to enable you to control externally the status of the outputs of the
card. You can add en external switch or a Safety Charge Pump to provide the
enabling signal. When the enable signal is not enabled, output signals sent high
impedance state. If you need the communication to be enabled at all times you can
provide the 5 volts directly from the source that is powering the card. Internally this
pin has a 4.7kOhm pull-down resistor.



That is not an e-stop input. It disables the outputs by putting them in tri-state mode. That should never be done while the drives are still powered as it allows for random noise to possibly cause the drive signals to switch unless the drive inputs are all pulled up or connected to something else such as an MPG. That input is for disabling the BOB and takes the charge pump out of the picture so that something like a manual pulse generator can take over driving the drives. The e-stop should be connected so it controls the charge pump or a specific input for e-stop as that will serve to shut down the I/O both in case of a computer crash or in case of an e-stop.

All you need to control is the charge pump. Mach will shut it down in an e-stop


5.1 Safety Charge Pump “SCHP”. (Pin 17)
This board takes advantage of Mach ability to send a specific frequency through
one of the pins of the parallel port when the program is in control of the system.
CNC machinery can be very dangerous, and you could have a risk of the machine
doing something different that what you intend the machine to do if the program
loses control of your system. Mach be can be programmed in a way, so when it is
“in control”, it delivers a 12.5 KHz signal through one of the pins. This card lets you
use this signal to work as an On/Off switch for your system, enabling a powerful
safety system for your equipment. If you ever had windows crash on you, then this
card is for you. The port can also do weird things while the system is coming up, or
down.

John Stevenson
06-28-2009, 08:53 PM
From the BOB manual:




That is not an e-stop input. It disables the outputs by putting them in tri-state mode. That should never be done while the drives are still powered as it allows for random noise to possibly cause the drive signals to switch unless the drive inputs are all pulled up or connected to something else such as an MPG. That input is for disabling the BOB and takes the charge pump out of the picture so that something like a manual pulse generator can take over driving the drives. The e-stop should be connected so it controls the charge pump or a specific input for e-stop as that will serve to shut down the I/O both in case of a computer crash or in case of an e-stop.

All you need to control is the charge pump. Mach will shut it down in an e-stop

That's what it does do.
removing 5v from EN disables the BOB.
removing 5v from pin 10 takes the charge pump out of the picture

Pin 10 is not ENable but both require 5v to work.
No 5v no ENable so dead BOB and charge pump switches off and kills Mach.

.

Evan
06-28-2009, 09:02 PM
John,

You don't want to switch the outputs to tri state mode while the drives are powered unless something else takes over on the actual connections to the drives. It is a very bad practice and can cause problems. Since there is nothing else to take the place of the BOB it should be enabled at all times on that input when power is on. Switching an output to tristate mode (high impedance) is essentially the same as cutting the wires.

John Stevenson
06-28-2009, 09:17 PM
Perhaps you need to explain this to Arturo Duncan as that's the method he uses and has been worked on by various people on many different drives including Gecko's, hence the C11 G[ecko]

Why Jim's system doesn't work I can't comment but I can say that many, many people have followed this wiring with no problems at all.

Do you have this board fitted to your Xylotex powered machine ?

.

Evan
06-28-2009, 09:45 PM
No. Regardless, I am going by the manual description. The buffer chips used on this board are the 74ACT245.

From the data sheet:
http://www.fairchildsemi.com/ds/74/74ACT245.pdf


General Description
The AC/ACT245 contains eight non-inverting bidirec-
tional buffers with 3-STATE outputs and is intended for
bus-oriented applications. Current sinking capability is
24mA at both the A and B ports. The Transmit/Receive
(T/R) input determines the direction of data flow through
the bidirectional transceiver. Transmit (active-HIGH)
enables data from A ports to B ports; Receive (active-
LOW) enables data from B ports to A ports. The Output
Enable input, when HIGH, disables both A and B ports
by placing them in a HIGH Z condition.

High Z means High Impedance, just as it says in the manual. When the outputs are disabled it is the same as cutting the wires. Also, the manual for the BOB does not say that the enable input is to be used for e-stop or shutting down the drives. It is for essentially removing the BOB from the system by effectively disconnecting the outputs.

I don't care how many people have it wired incorrectly. That doesn't make it right.

John Stevenson
06-29-2009, 05:03 AM
Also, the manual for the BOB does not say that the enable input is to be used for e-stop or shutting down the drives.


Right, not for shutting down the drives - understood.


It is for essentially removing the BOB from the system by effectively disconnecting the outputs.



What part of "effectively disconnecting the outputs " doesn't relate to shutting down the drives ?

If you are trying your usual pedantic hijack just to prove a point then it's working but I couldn't give a rats arse.

Jim is asking for answers to questions, I have done quite a few of these conversions, helped out on others, Eddie [ Motorworks] comes to mind here on this list.

Over to you.

.

oldtiffie
06-29-2009, 05:09 AM
Wottsa "BOB"?

John Stevenson
06-29-2009, 05:20 AM
Break out Board,
Goes between the computer and rest of a CNC system to [a] protect the computer by isolating the signals
[b] give a clean signal to the drivers, many computers only put 3.3 / 3.5 volts out the parallel post which isn't enough to switch the drives, most expect 5 volts and
[c] Make life easier for connecting up.

.

oldtiffie
06-29-2009, 05:39 AM
Thanks John.

I am now much the wiser and better informed.

Evan
06-29-2009, 06:29 AM
What part of "effectively disconnecting the outputs " doesn't relate to shutting down the drives ?


The part where the ends of the wires are effectively dangling free with no termination. In order to ensure a safe condition of the drives the inputs to the drives must still be supplied with a proper signal level that is either high or low. If the input to the drives is left at a high impedance state then the wiring is able to act as an antenna for any stray impulses they may pick up from other electrical noise in the equipment and this could cause the drives to move the motors unexpectedly when they should be stopped. There should NEVER be any signals going to the drives that are in an UNKNOWN state when the drives are powered.

I am NOT BEING PEDANTIC. This is an ABSOLUTE requirement for a safe e-stop condition and isn't optional.

As this is a matter of importance I shall find some references to give you since there is a slight chance you may not take me seriously.

j king
06-29-2009, 08:14 AM
I sent an email to CNC4pc and ask them about my problem.

Evan
06-29-2009, 08:25 AM
Perhaps you have access to the British standards referenced in this text. This gives the gist of it.



THE EMERGENCY STOP SYSTEM

The design of the emergency stop system should take into account that,
hopefully, it will be used very infrequently but it must be available and ready
for operation at all times.

Operation in an emergency
The nature and operation of the machine must be considered. Is it safe to have the emergency stop system cut the power to the
machine drives and actuators? This may result in the hazard
“freefalling” leading to a more dangerous situation. Should the system actuate a brake or clamp? Would stopping the machine in position result in a worsening of an
injury? Should the system allow the machine to continue on or reverse to a
safe position?

BS EN 418 categorizes these considerations and BS EN 60204 further refines
these as follows:-

Stop category 0:-
Uncontrolled stop -- stopping by immediate removal of power to the machine
actuator(s), all brakes and/or mechanical stopping devices being applied.
Stop category 1:-
Controlled stop -- with power available to the machine actuator(s) to achieve
the stop and then removal of the power when the stop is achieved.

Stop category 2:-
Controlled stop -- with power left available to the machine actuator(s).
http://www.hs-compliance.com/uploaded/documents/THE%20EMERGENCY%20STOP.pdf


Note that the category zero requirements are the least demanding. In a CNC machine tool removing all power by simply shutting off everything at once will not ensure a safe condition immediately. In particular it can take several seconds for capacitors to discharge to the point where the electronics stop working and the motors stop turning. Also, simply removing the power can result in significant damage to the electronics.

In order to ensure a prompt stop the system must remain under control until it is safe to remove power to the drives and various motors. The axis drives should never have the inputs in an indeterminate state while the drives are still powered. The inputs to the drives should be frozen to a stable condition while either the drive motor power is brought down, which may take several seconds, or until the drive disable inputs have been asserted and sufficient time has elapsed to remove power. In the case of drives with ball screws the power should not necessarily be removed, especially to the Z axis, since that may result in a still spinning spindle descending under gravity to cause further injury or damage.

Instead the drives should remain powered but disabled as this will result in the drive motors being locked in place. With steppers and especially servos removing power from a motor allows it to turn relatively freely which may present a hazard unless the machine is equipped with axis brakes.

Simply disabling the outputs of a breakout board does not satisfy even the least demanding requirements of an emergency stop system. On my system the e-stop tells MACH to stop and simultaneously applies a disable signal to the drivers via removing the power of a hard wired relay with gold contacts. That takes around 10 milliseconds. When those contacts open they drop out the hold in power via NO contacts to the main power relay to the driver power supply. That removes AC input from the supply. That relay also applies a resistor across the output capacitor that dumps the charge to less than a couple of volts within about 250 milliseconds.

The logic voltage to the drives is left powered to insure the drives are in a stable switching condition while motor power is removed. This ensures the fastest possible stop of the drives and motors until drive power drops enough. Since my machine uses acme lead screws I don't need to worry about axis brakes. Also, the Z axis is fully balanced and will stay put even if the lead screw were removed.

Simply disabling the outputs of the breakout board in no way satisfies even the minimum requirement for an Emergency Stop. By floating the wires to the driver inputs it actually creates an unsafe condition if the drives are not also immediately disabled via separate wiring.

Barrington
06-29-2009, 07:57 PM
A bit of a red herring I think:-
By floating the wires to the driver inputs it actually creates an unsafe condition if the drives are not also immediately disabled via separate wiring This would be true if the drive control inputs were high impedance, however they are likely to be designed to have a low impedance pull-up (e.g. only a few hundred ohms on the Gecko drives) for the very reason that connections can come loose and go open circuit.

Using the enable input to kill the drive signals for a rapid 'get out of trouble' stop is an imperfect but simple and adequate solution in a non-industrial environment (and when using stepper motor drives which don't tend to have a 'runaway' failure mode).

It is however a 'category 2 stop' which technically cannot be termed an 'E-stop' under para 9.2.5.4.2* of standard EN60204-1...

(*Not from memory :)...see googlebooks for Practical Machinery Safety by Dave MacDonald, page 113)

Cheers
.

John Stevenson
06-29-2009, 08:17 PM
Definitely a red herring as Evan has latched onto the enable pin only on the breakout board as THE e-stop and quoted chapter and verse.

However who said this was the ONLY e stop ?

I was replying to Jims post about getting the BOB working, not a rundown of the whole system.

For reference we fit double pole E stop switches, one side controls enable and e-stop and then the charge pump as these are all interlinked on the C11G.

The other side which originally cuts power to the spindle motor has now been extended to cut power to the drivers as well.

Unlike a lot of home made machines where you can get away with anything, a lot of ours have to go thru CE and Chris Wood at LMS is having to get his thru whatever regs the US deem nessesary.

.

Evan
06-29-2009, 08:25 PM
This would be true if the drive control inputs were high impedance, however they are likely to be designed to have a low impedance pull-up (e.g. only a few hundred ohms on the Gecko drives) for the very reason that connections can come loose and go open circuit.


Red herring my ass.

Without that information confirmed explicitly I would not offer any advice other than what I have. Even with a low impedance input it is still very bad practice to supply any sort of digital circuit with an indeterminate state signal and then expect or worse yet depend on it to be predictable.


Using the enable input to kill the drive signals for a rapid 'get out of trouble' stop is an imperfect but simple and adequate solution in a non-industrial environment (and when using stepper motor drives which don't tend to have a 'runaway' failure mode).


Exactly what is it about the industrial environment that makes a difference? I don't think it is adequate and neither does anybody whose job it is to actually design e-stop systems. I designed my system "by the book" and I don't have to wonder if it's going to do something unpredictable when my fingers are potentially in harm's way. The "solution isn't "imperfect", it is patently unsafe. Hazards you can see such as unguarded belts you can deal with as you work. Equipment that suddenly jogs because of random electrical interference is not something for which you can compensate.

The poster is asking how to make his machine work. The only advice I will give is how to make it work properly.

Evan
06-29-2009, 08:29 PM
Definitely a red herring as Evan has latched onto the enable pin only on the breakout board as THE e-stop and quoted chapter and verse.



It's called the ENABLE pin, not the DISABLE pin.

John Stevenson
06-29-2009, 08:32 PM
It's called the ENABLE pin, not the DISABLE pin.

So when it's powered it's ENABLED what state is it in when it's not powered? UNENABLED ? DISABLED ? Disbanded? Disbarred ?

However who said this was the ONLY e stop ?

What breakout board have you got fitted ?

Evan
06-29-2009, 08:50 PM
I don't remember the model of the board I have and it isn't relevant. I'm not going to argue with you over this. I am not privy to the information that you have re this installation but the poster asked for assistance so the only thing for me to do is not make any assumptions that would result in a hazard. Suggesting that he ENABLE the board is a first step in troubleshooting the problem.

If there are other e-stop inputs fitted then why did you reply:


If you do that it will work but the estop won't disable the drivers.



The only safe assumption for me to make is that the enable pin is being used as the e-stop.

John Stevenson
06-29-2009, 09:51 PM
Never ASS UME

.

Barrington
06-29-2009, 10:08 PM
To be pedantic, an E-stop is neither a 'safety stop' nor a 'safeguard', and as such no fingers should be 'potentially in harm's way' during it's activation. (The E-stop is at a lower level in the heirarchy.)

Of course Evan's system as described is actually extremely safe, but appears to be using the same system for a safety stop and an E-stop and is therefore not actually 'by the book'...

.

j king
06-29-2009, 11:04 PM
Well CNC4pc never replied. Sucks cause now I have to travel Wed. for 3 or 4 weeks.Everytime I get to work on this I end up having to start over when I get back. 2 steps forward and 1 back.

I DO appreciate the help.

John and Evan.
I feel bad that it seems everytime I ask for help you guys get into a disagreement.You both are great assets to all here.

My project is making progress and tho I am stumped at the moment I will get past this.If I need to pitch this BOB then I will.

Thanks guys.

Jim

Evan
06-29-2009, 11:40 PM
Of course Evan's system as described is actually extremely safe, but appears to be using the same system for a safety stop and an E-stop and is therefore not actually 'by the book'...



It is "by the book". It uses air gap contactors to remove the power from the systems and those contactors operate in the absence of power. I didn't mention the spindle which is also controlled by the main power relay. The computer may control the spindle via a solid state relay but the relay mains power goes through the main power relay. Further to that there is a spindle disable toggle on the front panel of the controller that prevents computer control by hard grounding the logic signal.

Further, their are two Emergency stop buttons, one on the machine and one on the controller. They must be reset and then the power applied by pressing a guarded push button that takes 5 lbs of force to activate. Switching the controller off via the very easy to operate guarded lever switch is the safety stop.

John Stevenson
06-30-2009, 05:00 AM
Well CNC4pc never replied. Sucks cause now I have to travel Wed. for 3 or 4 weeks.Everytime I get to work on this I end up having to start over when I get back. 2 steps forward and 1 back.

I DO appreciate the help.

John and Evan.
I feel bad that it seems everytime I ask for help you guys get into a disagreement.You both are great assets to all here.



Thanks guys.

Jim

No need to feel bad about it Jim, when you come back email me and we'll go over it.
If necessary I'll ring you and we'll talk it thru, because of my service support arrangements with the Chinese all my National and International calls are free so don't worry about the time / cost.

They are not a hard machine to convert, I have personally done 7, still own one, and helped on probably the same amount.

Last I saw when I checked photocopiers never had BOSS 1's fitted.

.

Barrington
06-30-2009, 06:16 AM
I'm sorry if my pedantry was unclear - if any fingers etc. are to be put in harms way, then the machine should be put into a safety stop; the E-stop must not be used in this situation... 'by the book'.

Again, 'by the book', the E-stop must also be a separate sytem to the safety stop, and may be less stringent...

'E' is for emergency, not everyday. In the real world however...

Cheers

.

Evan
06-30-2009, 08:04 AM
Last I saw when I checked photocopiers never had BOSS 1's fitted.



Of course not. Xerox always produced their own controllers. This small machine had 4 or 5 fitted with the main controller being the UNIX powered computer at top. The only real difference is that the moving bits didn't have end mills fitted but instead things like lasers. I worked on these since they first came out in the early 80's. I'll wager you have no idea what is inside one of these. They have estop and interlock systems 10 times more complex than your average little milling machine. There are parts in this machine that can blind you or take your arm off at the elbow. Open any door while it's running and it must stop safely in less than 1 second. It also must do so without damage or setting fire to itself.

http://ixian.ca/pics6/xprint.jpg

John Stevenson
06-30-2009, 08:52 AM
I'll wager you have no idea what is inside one of these.

Of course I known what's inside one.
They contain a small pedantic boy who's job it is to stamp on the paper feed tray so it jams, screws other sheets up and crams them into the gear train on the end of rollers then takes unfused toner and spreads it on the one blank sheet it produces.

All photocopies work that way.

.

Evan
06-30-2009, 10:19 AM
That isn't a photocopier.

japcas
06-30-2009, 10:51 AM
Is that a film processing machine Evan?

Evan
06-30-2009, 11:29 AM
It's the first entirely electronic printing press. This was actually the vision of Chester Carlson, the inventor of the xerographic process. The one in the picture is the Xerox 9700 and it is a networked 2 pages per second laser printer.

That vision has been entirely realized now. Xerox now sells fully dry process wide format continuous feed presses that are network connected to the composition department and at the press of the enter key put out a finished product. It can be a newspaper or fully bound books all in full colour.

camdigger
06-30-2009, 11:32 AM
That isn't a photocopier.

Potaatoe -potatto ............ still an electronic image device that uses toner:rolleyes:

Evan
06-30-2009, 11:39 AM
It produces originals, not copies. Regardless, it is far more complex than simple devices like cnc milling machines and is stuffed with all the same sorts of technology and much more. The training course for that machine was two months of work days at the main training centre in Leesburg Virginia and that assumed you already had years of experience and prior training.

camdigger
06-30-2009, 11:48 AM
It produces originals, not copies. Regardless, it is far more complex than simple devices like cnc milling machines and is stuffed with all the same sorts of technology and much more. The training course for that machine was two months of work days at the main training centre in Leesburg Virginia and that assumed you already had years of experience and prior training.

Put all the lipstick you want on that pig, it's still an electronic image device that probably uses toner....:rolleyes:

John Stevenson
06-30-2009, 12:23 PM
http://www.youtube.com/watch?v=b7HYYKEbfLk

.

Evan
06-30-2009, 12:53 PM
Put all the lipstick you want on that pig, it's still an electronic image device that probably uses toner..


Yes, that is part of the xerographic process. Do you have a point?

camdigger
06-30-2009, 12:58 PM
Yes, that is part of the xerographic process. Do you have a point?


YUP, the posts pertaining to xerographic process, digital imaging, and stuffing yer shirt have Sweet F*^% all to do with the subject matter of the post and serve no purpose other than to inflate your already substantial ego and your post count.

Objection sustained - lacks relevance ...........

Evan
06-30-2009, 02:42 PM
YUP, the posts pertaining to xerographic process, digital imaging, and stuffing yer shirt have Sweet F*^% all to do with the subject matter of the post and serve no purpose other than to inflate your already substantial ego and your post count.


In case you didn't notice, I didn't bring that subject up in the first place. I don't give a rat's ass about the post count either. Apparently it bothers you quite a bit.

The subject is e-stop systems and since John brought my experience in working with photocopiers and related equipment into the exchange it became relevant to point out that my professional training and experience with those systems highly qualifies me to judge the merits of identical systems in other machine applications

You on the other hand don't seem to have much to contribute.

John Stevenson
06-30-2009, 02:49 PM
In case you didn't notice, I didn't bring that subject up in the first place. I don't give a rat's ass about .................................................. ...


Hey that's my line, did you photocopy it ?

And before you post back, happy 1/4 Centenary :D :D

.

camdigger
06-30-2009, 03:55 PM
You on the other hand don't seem to have much to contribute.

Nope, You shouted me down in the past on subjects you had only google knowledge and third hand hearsay on. I know it's pointless to take on a self proclaimed former debate champ in what he claims is his area of expertise.

I have shovelled enough Bull, cow, calf, pig, and chicken sh*t to recognize it when I see it, and sometimes can't resist the urge to call 'em as I see 'em.

I'll take my meager credentials and wander off... it's lunch time for me...

Evan
06-30-2009, 04:56 PM
I have shovelled enough Bull, cow, calf, pig, and chicken sh*t to recognize it when I see it, and sometimes can't resist the urge to call 'em as I see 'em.


My advice is don't make your own investing decisions. Your judgment appears to be lacking.

I started with Xerox in 1975 and didn't go for my first training course until '76. That didn't stop me from doing a good job since I already knew all the principles involved.

http://ixian.ca/pics6/x.jpg

John Stevenson
06-30-2009, 05:52 PM
http://ixian.ca/pics6/x.jpg

Impressive, what happened to the first two quarters ?

Anyway didn't you once say that as it was a remote area you had to work on your own and cover large areas ?

team leader of one ? :rolleyes:

Somewhere I have a driving certificate issued to me by Cripps Ltd who at one time were the leading plant operator and repair agency in the UK

This certificate told everyone [ I presume myself as well ? ] that I was allowed to drive Graders, excavators and bladed shovels up to and including D xxx's [ or something ]

However seeing as I never even got near any of this gear I didn't have a clue how to start the bloody things , let alone drive them but I had the certificate.

Ironically it didn't allow me to drive the big off road dump trucks which is what I was employed to repair.

.

camdigger
06-30-2009, 07:06 PM
My advice is don't make your own investing decisions. Your judgment appears to be lacking.

I started with Xerox in 1975 and didn't go for my first training course until '76. That didn't stop me from doing a good job since I already knew all the principles involved.

http://ixian.ca/pics6/x.jpg

Welp, "spit"............ I ain't gonna pit my 25 year old Engineering degree and 20+ year old in-house training on proprietary computer controls against anyone who has modified equipment and met current specifications.

I know when I'm out gunned, do you? What's next? buggy whip safety lanyards?

My investments held most of their value (90%+) in the last 10 years, yours?

John Stevenson
06-30-2009, 07:45 PM
Welp, "spit"............

My investments held most of their value (90%+) in the last 10 years, yours?

INCOMING>>>>>>>>>>>>

camdigger
06-30-2009, 08:45 PM
INCOMING>>>>>>>>>>>>

Seems the self declared debate champ is resorting to misdirection to avoid further pursuit of an indefensible position...........

WTF does anyone's investment record or advice have to do with E stops anyway? Maybe the Xerography guru from the back and beyond ( But F*&k nowhere) can make the connection fer the rest of us pore unwashed masses.

Maybe the Williams Lake Pontiff is missing civilization and is a bit shack-wacky??????????????

Evan
06-30-2009, 10:24 PM
My investments held most of their value (90%+) in the last 10 years, yours?


Last ten years I have made about 10% ROI each year average. Last year was only about 6% since I moved everything to cash in early summer. I bought back in this year. Last I checked I am ahead nicely.


WTF does anyone's investment record or advice have to do with E stops anyway?

About as much as your shoveling piles of chickenshlt does. It's about judgement in general and yours in particular.



Impressive, what happened to the first two quarters ?

Anyway didn't you once say that as it was a remote area you had to work on your own and cover large areas ?

team leader of one ?

I started in the middle of second quarter. Had to work a full quarter to show up on the survey results. Began work in Victoria and worked there for a year and 6 months before moving here.

That has nothing to do with anything except to show when I really did start work with Xerox. Of course it's possible that in my 23 years of repairing broken proprietary computer controls I may have run into some of our friend's work, non-functioning of course.

Xerox had an interesting policy regarding new hire engineers. The had to spend their first six months riding with the field service reps so they could learn how to design equipment that can actually be repaired when it breaks.

camdigger
06-30-2009, 11:14 PM
That has nothing to do with anything except to show I really did start work with Xerox.


Whoopeee..


More rhetoric and misdireection from the self proclaimed debate champeen..........

macona
07-01-2009, 05:38 AM
The Charge Pump feature in breakout boards is intended only to keep the pulses that get sent out the parallel port from activating anything during the PC's startup. Windows will probe the port looking for peripherals. It is not intended to be any sort of software safety mechanism. This comes from ArtSoft themselves.

I use two of the C10 boards in my mill. The charge pump board controls the EN input on the C10's to keep things off till mach starts up.

Evan, is that printer in the pic one of the ones that used small frame argon lasers?

Evan
07-01-2009, 05:49 AM
Yes. As far as I know Xerox was the first to develop a blue laser. It's an argon gas laser that normally runs around 50 to 75 milliwatts but can easily be tuned to upwards of 200 mw. :eek:

The interlock and safety systems rely not just on electronic and electrical methods but also on physical security including key lock switches and covers that must be in place to complete interlock circuits. Even the regular door interlock switches on the machines are designed to be difficult to causually defeat and require a small plastic key to cheat for trouble shooting.

Btw, the Charge pump is also to detect if the computer has crashed badly enough that MACH or whatever is no longer running. Machines such as above use a more sophisticated watchdog timer that works on a challenge/response type of system. If the remote doesn't answer it gets reset and a note entered in the log. The main controller also has a watch dog that it must actively reset every few milliseconds to prevent being reset itself.

macona
07-01-2009, 06:05 AM
I used to have a couple of them. I think they used Omnichrome 532 or ALC 60X lasers.

200mw is possible by replacing the single line TEM00 optics with Multiline, multimode optics. You dont have the focusable beam of a TEM00 beam but its good enough for light shows which was what most were doing with them. You also have to run them at full 10 amps tube current which kills their life. The "gold" power supplies used in some xerox printer could not be ran at this current without frying.

I used to have a Omnichrome 643 as well. Argon/Krypton white light laser. Put out Red, Yellow, and Blue. Now all I have is a ILT head that I need to build a power supply for.

We are retrofitting an old Clausing lathe at work with a new Milltronics control package. It had a Bandit on it. I will have to look at the details of how its e-stop works. I do know there is a contactor between the VFD and the motor (Yes, between the motor and VFD, but does not open till 4 seconds after the VFD stops) and contactors on the bus side of the servo drives. Machines that have a Z axis should have a motor with a brake that is energized to release.

The Mitsubishi servos I am using on my lathe have a dedicated e-stop input that kills power and dynamically brakes the motors to a stop.

Evan
07-01-2009, 06:44 AM
Xerox used to own Pasadena Electro-optical systems as well as Spectra Physics. It was one of them that developed the argon laser as well as inventing the laser diode. It's been a long time since I worked on those systems and I have tried to forget as much as possible to make room for more important details these days like our anniversary. :eek:

Most of the motors in that machine have integral brakes. A lot of them operate as a brake disk on one end of the armature that is pulled away from the pad when the motor is energized, which centers the spring loaded armature. Remove power and the spring forces the disk against the brake pad. Simple and reliable.

lazlo
07-01-2009, 11:46 AM
The Mitsubishi servos I am using on my lathe have a dedicated e-stop input that kills power and dynamically brakes the motors to a stop.

Most VFD's have that same function for the external E-Stop input.

camdigger
07-01-2009, 08:03 PM
Most VFD's have that same function for the external E-Stop input.

Do they do this by dc injection into one or more "phases" of the three phase motor, or do they divert back EMF from the motor through a resistor?

lazlo
07-01-2009, 08:59 PM
Do they do this by dc injection into one or more "phases" of the three phase motor, or do they divert back EMF from the motor through a resistor?

When the external E-Stop signal is asserted, the VFD stops the motor as quickly as possible: it uses the external braking resistor if there is one, and DC injection braking if there's not. The output FET will then remain disconnected until E-Stop is de-asserted.

I just checked three different brands of VFD I have (Hitachi, Samsung, and Teco) and they all specify E-Stop the same.

Please note that "Stop" on the front-panel of the VFD (or the "Stop" signal on the IO block) doesn't work the same way! The VFD will decelerate the motor however you have it programmed -- 4 - 30 seconds is common, and the VFD will remain active (the output FET is enabled and ready to start the motor back up).

macona
07-01-2009, 11:40 PM
My altivar 18 has two different stop modes at the terminal strip. Normal decerated stop and stop as fast as it possibly can mode where the drive stops the motor as fast as it can without throwing an alarm from overload or overvoltage.

My VFD uses dump resistors and has DC injection.

The mitsubishi servos basically short one or two of the windings in estop mode if selected in the parameters.