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Buckshot
07-22-2008, 12:04 PM
I just got an Enco 9x42 mill (DRO, powerfeed) and bought a TECO-Westinghouse VFD to go with it. While the VFD's instructions aren't in Chinglish, to me they are a bit nebulous. The manual covers about 8 different models in what appears to be 3 different housing designs.

It is also written with the understanding that you are already fully versed in VFD operation, nomenclature, proceedures, and technical aspects. There are no examples for possible machine variations etc. Nor is there anything written for the uninitiated (Boneheads like me).

The power input, and output to the machine are clear (input & output connections on the VFD itself)) so far as the VFD is concerned, at no point does it say to wire directly to the motor or to wire to the existing motor controler switch. Is there a universal answer, like VFD's ALWAYS go direct to the motor, etc?

Don't wanna let the smoke out!

Rick

lakeside53
07-22-2008, 12:23 PM
VFD's connect directly to the motor...

gellfex
07-22-2008, 12:53 PM
If you are reluctant to disassemble the tool's switching, what I did on my drum switched lathe was simply put the switch in "forward", and removed the switch arm.

murph64
07-22-2008, 01:12 PM
Would there be any problems with connecting the VFD to the machine so it's drum switches can be used for forward or reverse? Problems other than wasting a feature of a VFD, that is.



Andy

RobbieKnobbie
07-22-2008, 01:19 PM
One of the great things about having the VFD is the flexability it affords compared to a drum switch. By keeping the old drum switch on there you're giving up a lot of what you paid for when you bought the VFD.

Forget the old switch, make up a nice panel with a for/rev switch, a start push button, a stop push button and a mounted pot. Trust me, you'll be SO happy you did.

You can get the basic parts from Radio Shack or Jameco... or you could go all industrial and get parts from McMaster or Automation Direct. I get all my stuff from AD, so I'm a little biased, but their stuff is very nice for the money.

Your TECO manual should have a wiring diagram that shows you how to connect the switches etc. You may also have to change a parameter to tell the VFD which switch layout it has connected to it, but that's not typically a big deal at all.

sch
07-22-2008, 01:31 PM
You only 'waste' a feature on the VFD if you want to. Most VFD
these days have more features than cell phones, most of which
are already wasted on users for lathes, mills and mill-drills.
VFD HAS to be direct connected to the motor and should be
direct connected to a disconnect switch which can handle the
total power to the VFD. This switch can be fused or otherwise
protected against overload. VFD itself is supposed to protect
the machine, so no protective gear between VFD and motor.
A study of the manual will eventually reveal that a series of
single pole single throw switches can control ON OFF REV and
FOR depending on how the VFD is configured. These can be
milliamp rated switches as they operate at 10v or so. A standard
drum switch or the existing machine switch can be commandeered
to perform this function
nicely. The manual for the mill should have a wiring diagram and
the wires should be easily disconnected and reroutable to allow the
existing machine switch to control the VFD. Mount the VFD somewhere
where chips can't bounce or fly into its ventilation opemings, if it is
not in a sealed box. It is nice to be able to see the read out of the
vfd frequency, and any messages it has for you. Some VFD have the
output herz adj pot on the housing, some do output herz adjust with
up down switches on the VFD housing. A 5k or 10k pot from your
local electronics shop (preferably one costing $5-10) and a sheet metal
round cornered 110v box with a face plate from HD for $3 or so can
be mounted on the machine for remote control very easily.

Bill Pace
07-22-2008, 01:53 PM
I've got the ENCO 9x42 also and used a Hitachi VFD....

The on/off sw breaks the power TO the VFD, the fwd/rev/center off sw controls the VFD's power for the motor. The drum sw is still functional, though I dont use it ... it will put the motor in the high speed mode and will run it .... but it (the VFD) doesnt like it and will go into a fault mode pretty easily, so,-- as I say I dont use the drum sw. (With these wunnerful VFD's dont really need it anway, just dial in some more hertz and you can gain a bunch of rpms if needed)

http://i22.photobucket.com/albums/b301/pace1980/IMG_0619.jpg

mike petree
07-22-2008, 02:34 PM
Wired mine up like Bill P. Works very well!

gellfex
07-22-2008, 02:42 PM
One of the great things about having the VFD is the flexability it affords compared to a drum switch. By keeping the old drum switch on there you're giving up a lot of what you paid for when you bought the VFD.

Forget the old switch, make up a nice panel with a for/rev switch, a start push button, a stop push button and a mounted pot. Trust me, you'll be SO happy you did.

You can get the basic parts from Radio Shack or Jameco... or you could go all industrial and get parts from McMaster or Automation Direct. I get all my stuff from AD, so I'm a little biased, but their stuff is very nice for the money.

Your TECO manual should have a wiring diagram that shows you how to connect the switches etc. You may also have to change a parameter to tell the VFD which switch layout it has connected to it, but that's not typically a big deal at all.

Much depends on the wiring options, and whether you can use momentary switches or not. Ex: on my Rockwell drill with a TB Woods VFD, I have on the original front switch plate a momentary center off DPDT toggle switch, and a mushroom cap OFF switch. The momentary contact is FORWARD or REVERSE, with no need to turn off between, the unit decelerates and reverses intelligently. Also, the OFF can be easily hit with my forehead in case something grabs the bit on an unclamped piece. Unfortunately my Hitachi on the mill can't be wired similarly, they simply don't allow the momentary functions, I've talked to the techs about it. Odd, but each make is apparently different.

The Woods didn't have a speed pot, so I just added one, drilling a hole in the front of the case.

jkilroy
07-22-2008, 02:43 PM
No, No, No, No, No

Couldn't enter just No, the message was deemed to short, even though it was a direct, and correct, answer to your question.

Buckshot
07-23-2008, 04:47 AM
I appreciate you guys taking the time to respond. What some of you have posted makes some of the stuff in the booklet a bit more understandable.

http://www.fototime.com/C12AB0477A094C7/standard.jpg http://www.fototime.com/F235813ED18BC94/standard.jpg

Front of the unit. The 3 wires currently hooked up are the wires from the motors' factory installed rotary switch. I understand now I need to wire the motor directly. The lower terminal strip has 8 connection points. From the left, 3 are for power in (2 hot legs, 1 ground). The 2 in the middle (marked P and R ) show in the book for a "Braking Resistor (option)". Then the already mentioned 3 wires to the switch.

I was just going to try and write out what each of these things showed in the book for the upper terminal strip. That was a PITA to try and make clear so I just took a picture. One page and the next:

http://www.fototime.com/0ADC1AF5CE34052/standard.jpghttp://www.fototime.com/101F187892D8E19/standard.jpg

Before I bought this I asked the people if this unit was all I needed, and I was told yes, it's all I need. Seems to me that terminal strip is there to hook SOMETHING up, otherwise why have it?

Be gentle! :-)

Rick

ammcoman2
07-23-2008, 09:01 AM
Rick, I have 3 of these units in my shop. One is a 120v input and the other two are 220v single phase input (all L1 and L2 only). I am not sure if the one you have is a 220v single/3phase input as L1, L2 and L3 are shown on the diagram.

If the unit is a dual function input, and you are inputting 220v single phase, you need to hook up L1 and L2. There is no neutral involved in a household 220v input in North America. But, check the booklet first as I am not familiar with this particular unit. The ground wire must go to the external bar at the bottom of the casing (it is supplied in a small clear plastic bag). The ground to the motor then goes from this strip.

In all cases I have used the existing drum switch hooked up to 3, 4 and 5 on the upper terminal strip (I just prefer the feel of a drum switch). The pot goes to 8, 9 and 10 with 9 going to the center position. The programming has to be set for external switching.

As others have said previously, you must have a switch or C/B between your outlet and the VFD. On the 120v setup I have a switch but the two others have C/B's in the circuit as they were there before. I didn't program the C/B feature that is available in the VFD's

If you need more info re the programming, let me know.

Geoff

Dave Converse
07-23-2008, 12:05 PM
Hi Buckshot,

My TECO is a bit older than yours. I wired mine up the same way as Geoff describes in order to keep my BP's switch the same as I was used to at a shop that had 3-PH. My TECO has 2 terminals for "remote" switching that I used the BP switch for.

lazlo
07-23-2008, 12:44 PM
I have used the existing drum switch hooked up to 3, 4 and 5 on the upper terminal strip (I just prefer the feel of a drum switch). The pot goes to 8, 9 and 10 with 9 going to the center position. The programming has to be set for external switching.

I did the same thing on my lathe -- re-used the drum switch as the external signal inputs for forward and reverse.


As others have said previously, you must have a switch or C/B between your outlet and the VFD.

That's NEC code, but I don't have a shut-off switch between the outlet and the VFD on any of my machines. I just leave the VFD's running all the time.

Get 'R Done. :D

Richard-TX
07-23-2008, 12:45 PM
Rick,

The FM50 is a basic unit and is simplicity itself to integrate.

The best way to learn about the FM50 is to do it.

The rules are:

1 - Never apply 120 or 230 volts AC to any of the low voltage control terminals. That will let the magic smoke out. (there are exceptions but they are fairly rare.)

2 - L and N are your single phase power connection points.

3 - Wire the motor direct to the VFD. NEVER put anything between the VFD and the motor other than a piece of wire.


Out of the box you control the VFD from the front panel. SO by default, you don't need anything.

If you want to use external or existing controls, then you start what I call the integration process. This can be easy or difficult depending on your level of experience.

The fm50 external controls work on a contact closure basis. Once the right parameters are set, a jumper wire from +12 to FWD will cause the motor to run forward. Take it away and the motor will stop. Same with the REV, SP1, RST lines.

What makes things a challenge when wiring external controls is the fact that you will need some control wiring. This is something as simple as two conductor stranded wire or a 10 conductor cable. It all depends on what you need.

A drum fwd/rev switch is simple to wire to the FM50. A 3 conductor cable is needed in that case.

When integrating existing controls, make sure there is no connection to 120 or 230 volts AC anywhere.

That should get you going.

Here are some diagrams that may help. The first one is for the 120 VAC input version of the FM50. Your FM50 is the 230 volt version so power terms 1(L) and 3(N) are your supply connections.

http://rich.homeunix.com:443/VFD/vfd-wire-basic.JPG

This next one shows how to wire "3 wire controls" to a FM50. Note that you lose dynamic braking using this scheme. If you want 3 wire controls and dynamic braking then you have to add a relay.
http://rich.homeunix.com:443/Electrics/3wireVFD.JPG