# VFD REMOTE SWITCHES



## chopper steve

Got my teco fm50 up and running. Now for the remote switches.  Don't know much about these, so if anyone can post some links or part numbers for the right ones, That would be great. Not sure if the switch should be single/double contact , n o, n c.??????  HELP!!!!!   Just looking for fwd/stop/rev and a pot for motor control. I have searched in here with no luck.  Thanks   Steve


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## Tony Wells

Here is a link to the manual for anyone who wants to read through it:

http://www.tecowestinghouse.com/Manuals/FM50 Instruction & User Manual_0405.pdf

I'll have a look and see what we can do to help.


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## rdhem2

The control wiring to VFD's is low voltage.  Varies by manufacturer but usually under 30 volts.  Most any type switch will do in a pinch.  VFD's take a normally open input from a common source of reference.  That said you can change to NC operation via programming but why change unless you really need too.  Just something else to remember. 

What is more important is the type of signal, momentary or maintained.  Momentary-pushbutton.  Maintained-selector switch. You will have to program the VFD to tell it which type you are using.  Pushbutton-3 wire control.  Selector switches-2wire control.  This activates the internal programming to include a maintaining circuit for the start button.  For the sake of safety (my big problem) you should use momentary inputs to forego accidental start on power up unless you are experienced in control wiring and know how to eleviate this potential problem.  REASON: If you are operating your machine and there is a power outage, momentary or sustained you do not want the machine to self start upon the return of power.  So far we have three pushbuttons.  FORWARD.  REVERSE.  STOP.  Next the speed control.  This is only a 3 wire resistive reference for the drive so the least expensive route is a trip to radio shack for a rotery potentiometer in the 3K to 10K range.  Not critical as this is only a reference input and the drive will know how to handle it.   Don't forget to get a knob either, just a finishing touch to your pushbutton enclosure and a switch label if they have one.  I am big on neat, professional, looks.  After all, you have to look at it from now till forever.

Switches.  I really like the 22mm european DIN style.  Usually pretty affordable.  I don't know your sources but a oil tight 22mm pushbutton with a NO contact block costs me about $9 or less.  This size button mounts in a 7/8" punched or drilled hole, 1/2" conduit size so you should not have to buy any more tooling.  There are operators available for your speed control to match your PB's but the are horrendiously expensive.  In the $65 + range.  Oil tite means just that.  They are gasketed and sealed against liquid entry into the enclosure be it oil, coolant, water whatever.  In other words made for and intended for the purpose.  The larger operators use a 1 7/32" hole usually with a square notched locking hole to prevent turning after installation.  But they are way more expensive, require a larger enclosure and just aren't as cute as the smaller ones.  AB and Telmecinique (SqD) are two very good brands.

There you have it.  There are a thousand other ways to do the same job, this is just one.  If you need more features like keyed lockouts, jog functions etc we can add anything.  As I used to tell my customers, "With your money and my brains, we can do anything!"  Boy do I tend to be mouthy.

Get this done so you can start making *SWARF*.


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## Tony Wells

Looks like page 17 has the basics of the wiring. The various control inputs appear to be momentary contact switches, typically push-button. There will be some parameters to set to make sure things act the way you want them to. That's what the rest of the manual is for.


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## Kennyd

Steve, you need a DPDT or SPDT center off switch to control the FWD/OFF/REV.  This will have three positions.

Depending on your machine, it may be possible to rewire the factory switch to control the VFD.


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## Kennyd

Tony Wells said:


> Looks like page 17 has the basics of the wiring. The various control inputs appear to be momentary contact switches, typically push-button. There will be some parameters to set to make sure things act the way you want them to. That's what the rest of the manual is for.



FYI Tony, they do not have to be momentary on the FM50-they can be but dont have to be.


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## furpo

TheFM 50 is coverd pretty well @  http://www.practicalmachinist.com/v...rters-vfd/wiring-teco-fm50-mill-lathe-220678/


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## CluelessNewB

The TECO FM50 works best with sustained switches rather than momentary switches.  The FM50 will NOT do normal "3 wire control*" without external relays.  So the easy path is a SPST center off switch for forward/off/reverse and a 10K ohm potentiometer.  Look for a 10K ohm linear taper potentiometer rather than logarithmic (audio) taper.  Either will work but the linear will give a more even control over the range.  You can add a momentary contact for an emergency stop button, if I remember correctly it would be NO (normally open), it's been a few years since I hooked up an FM50, personally I think the user manual is not this units strong point.   

Many other TECO VFDs like the N3 and 7300 can do 3 wire control out of the box. 

*3 wire control use two momentary contact switches a NO for start and a NC (normally closed) for stop.  The control stations used with a typical magnetic starter are this type.


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## Kennyd

furpo said:


> TheFM 50 is coverd pretty well @  http://www.practicalmachinist.com/v...rters-vfd/wiring-teco-fm50-mill-lathe-220678/


It's covered pretty well here one this forum as well, no need IMO to link to another.


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## MikeH

CluelessNewB said:


> The TECO FM50 works best with sustained switches rather than momentary switches.  The FM50 will NOT do normal "3 wire control*" without external relays.  So the easy path is a SPST center off switch for forward/off/reverse and a 10K ohm potentiometer.  Look for a 10K ohm linear taper potentiometer rather than logarithmic (audio) taper.  Either will work but the linear will give a more even control over the range.  You can add a momentary contact for an emergency stop button, if I remember correctly it would be NO (normally open), it's been a few years since I hooked up an FM50, personally I think the user manual is not this units strong point.
> 
> Many other TECO VFDs like the N3 and 7300 can do 3 wire control out of the box.
> 
> *3 wire control use two momentary contact switches a NO for start and a NC (normally closed) for stop.  The control stations used with a typical magnetic starter are this type.



Here is an example of doing something similar to what CluelessNewB is talking about. This is the wiring diagram I created for putting a VFD on my lathe. It uses relays to maintain sustained conductivity while using momentary switches and a potentiometer for speed control. I set it up with reverse, jog, variable speed, and both emergency and normal stop. The wiring for these functions and what type of controls you need all depend upon your VFD. Get to know the manual well, it is your friend. I hope this clarifies some of the mystery for you.


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## British Steel

No problem at all putting the starter on the supply side, and it'll add a bit to the.machine's safety - what you shouldn't do is put any switchgear between the VFD and the.motor, that can let the magic smoke out!

Dave H. (the other one)


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## Kennyd

Reaxun said:


> I have a question around this topic I think, my lathe was a single phase 220v 2hp motor with a mag reversing starter that you controlled by a lever under the front of the carriage, down was forward and up was reverse. I am changing this setup to a VFD, I have increased the motor to 3hp, purchased a IMO Jaguar VFD of the correct size for the motor, the motor is a VFD rated motor and I have a remote control station that has run, forward, reverse, stop, jog and a pot for speed on it. My question is can I use the existing mag starter to send the power to the VFD so that I may continue to use the original switch or will I ruin the VFD by interrupting the feed line to it ? The VFD is a 240v 1ph input to a 240v 3ph motor.



Remember that you may NOT have any switches between the VFD and the motor, you can only switch the feed side of the VFD.
IMO, you should eliminate the mag switch, then rewire the other controls to operate the VFD.

Or did I misread your question?


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