VFD Setup for controlling multiple machines

This diagram is TECO FM50

FM50page17wiringdiagram-EDITING.gif~original





You can daisy chain like this.
This shows 3x motors but you can keep going like this.
vfdtoswitch3motors-1.jpg~original
 
You will be using the potentiometer, not the Current input, so you do not need to connect anything to FM+.

Just connect +10V and 0V to the ends of the pot and VI to the slider.

When you first start the unit, set the pot to the middle and then make an adjustment. If the speed goes up when you expect it to go down, swap the wires in +10V and 0V.
 
dluxhvac
The hollow grind jig works very good but I use it mostly to just make a grind to center my cutting edge. I do all flat grinds.
But I don't what to hijack this thread about the main reason it was started.
 
Ok this is going well...mostly! I've setup the external controller box with the On/Off switch, forward/reverse SPDT switch, and the potentiometer connected to a 12 foot lead of 8-stranded cable going from the box to the VFD.

The good news is, On/off and Forward/Reverse is working perfectly using the external controller!

Bad news is, potentiometer seems to have no control at the moment. I'm doing my best to troubleshoot it as best I can but can't seem to find where the issue is. All connections should be good, I've swapped the 1&3 connections on the Pot, tested for continuity, messed with the VFD parameters etc. No dice so far. I'll have to refer to the manual again, which means I'm in for a night of many, many wtf moments while deciphering poorly translated technical reference for something I have only a loose grasp on to begin with! Perhaps pics would help. I'll work on that :p

Thanks Tim Gunn, Kevin, Count and everyone for the help so far.
 
Actually, I think the pot is recommended to be 10kOhms, but I have found that anything from 2.2 kOhms to 10 kOhms will work on every VFD I've had. It is used as a Voltage divider in this application and therefore does not need to have an exact resistance value.
 
IIRC the external pot function had to be chosen on mine. I think there were 2 options, default being the up/down arrows and 2 for external pot.
 
Interesting thread.

Should one choose a standard TPDT switch or a rotary cam switch for switching between two motors with one vfd?

What are the pros and cons?
 
I figured it out! After going through plenty of threads in the cnc and machinists forums I found a post where someone mentioned needing to change over a small jumper block next to the external connections terminals.

On mine it was to the right of the green terminal and allowed you to choose "vi" or "vr" via a small black jumper box (see photo below). Since my VFD already had a pot installed on the face of the control panel I think it was overriding my external pot until changing over the jumper pin to "vi".

Also shown is the current setup for the simple external control box. It works like a charm! 12 ft. cable lead so I can take it around to each of the machines.

For now I'm going to use the "plug" system despite the inconvenience factor and then tackle the "switch box" as a separate project in the near future.

9b6971fe3d1e78f16f79eae092284b8f.jpg


b28c4e807d814c1143c2253a7c5e1bcd.jpg


f81f14df51c4c595dd9fa8a3782660f8.jpg



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Yeah man. The control box on a leash is the way, that's what I've had for a while and it is effective. IR remote would be cooler, but it would be a big PITA using an Arduino and logic circuits etc to make it work. Who's got time for that?

I have two belt grinders, a disc grinder, and my surface grinder in one array, and my machines- power hammer, small lathe, milling machine, and vertical bandsaw on the second array.

I use triple pole/double throw switches, chained up.

The controlled 3 phase power goes out from the VFD to the first switch. This picks "Grinders" or "Machines."

If "Grinders" is picked, power goes through the wall to the grinder subpanel. On it is a switch that picks the two belt grinders, or the disc and surface grinders. Flipped to "Belts" power goes to a switch that picks which belt grinder, and flipped to "Disc" power goes to a switch that chooses the disc or surface.

If the first switch is flipped to "Machines" rather than "Grinders," power goes to a second switch, which offers "Lathe/hammer" or "Mill/saw."
In either case, power moves to a final switch which picks the machine wanted.

It is a hierarchy of switches, choosing parallel categories. The other way, and I've done it in the past, was to simply add another switch with every machine, chained onto one side of the last switch- every switch picked either it's machine, or the next switch, which did the same.

The way I have it now is better- any machine picked goes though only four switches, and it is easier to add a machine when necessary. With the series system, I liked to have the heavier Hp machines earlier in the switch bank, so if adding a 3hp machine, I'd have to re-wire a lot to avoid it being on the end of the line.

The only problem now is when I have students or friends over working, and I can't run say the hammer or mill while grinding is going on.
I'm working on circuitry to be able to run the mill, hammer, and surface grinder from my Phase Perfect when I need to, to free up the VFD.

Hope that helps. Get in touch with me any time if you have questions I might be able to answer...
 
Hey Salem thanks for the detailed reply describing your system! I'm very happy with the first day of the "control box on a leash" method :D

IR Remote WOULD be great, but yea man, wow that'd be a side-project OF a side project haha (side project if knifemaking is the goal in mind though I often wonder if I'm into the knifemaking for the machine builds or the machine builds for the knifemaking??). Regardless, I love both aspects of being a knifemaker. Shop setup and building new equipment has always been a lot of fun. And so worth it! The feeling of dialing in the EXACT speed you want on your machines with the turn of a knob is really amazing.

The switching bank will be the next step in the project. Salem I'd love to chat but my DM capability in bladeforums seems to have reached its limit. I'll try you at your website or....email perhaps? Thanks for the offer to discuss with me :)

I'll try to create an updated diagram too for anybody else interested.
 
So, here's an updated diagram showing what I have in mind for the switching (thanks to Salem and everyone else's description of how to set this up).

I'm not gonna tackle this YET because the plug system isn't so bad at the moment, so I'll wait until I setup my bandsaw with the 3-phase motor and actually have my new grinder completed (yay!).

There may be more changes to this but this is what I have in mind for the whole setup. I may install 2 rotary switches after the main machine bank switch in case I add more machines later:

K9dnjxL.jpg
 
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Yeah man, that's the system I have, with a few less machines. Nice diagram. Now I can point to that rather than use a bunch of words, when people want details on switching!
 
Thanks currenthill I'll replace the original incomplete diagram from the first post with this one so it's not confusing


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As many, I also played with this idea from time to time, but I always thought about a travelling VFD instead of lots of wiring and toggles. The idea came from the docking stations used for laptops in the past.

For a multipurpose VFD docking station (DS) you would need two connectors:

1) 6 way power connector or two 3 way, one for the motor and one for mains
2) multi signal connector:

3 wires for speed potentiometer
3 wires for start stop
3 wires for fwd/reverse

On some VFD some of these signals, for example DC ground are the same, so less signal wires are needed.

What do you guys think?


Pablo
 
Hey Pablo, I think that could be useful in a situation where there are machines spread out over a very large area, but it seems also like it would be quite a bit more work than the remote control method because you'd need a means for input power (with breaker switch) as well as 3-phase output, and control connections at each station. Also you'd have to carry around the VFD unit itself which would be prone to dropping (in my case at least :p). But perhaps if tools are in two separate rooms I could see it being worth it.

Really, after setting this up I love the versatility of it. For the mobile VFD method like you're mentioning, I'd just get some kind of multi-pin male/female connector for the controls and then a female/male plug for the input and then a 3 phase male/female plug pair for the output. I ended up needing only used 6 wires total for the control connections to do on/off, forward/reverse and speed pot.
 
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