3 wire control for Fuji VFD question

Hi Group,

I have a Fuji Frenic Mini VFD (similar if not identical to the GE/Fuji AF 300) and am having problems hooking it up to 3 wire control.

First, my concept of a 3 wire control is a FWD/REV selector and a NO momentary run button, with a NC momentary stop button. Please correct me if this is wrong.

The VFD is controlling a 1 HP drill press. I have it hooked up now with an on/off toggle switch for the FWD function and it works fine. The manual is not very clear about 3 wire control and I have tried various function codes but still no progress.

Any help would be appreciated.

Chuck
Burbank, CA

Chuck,

I'm not real sure of what you are after. I looked at the brochure for the Fuji Mini VFD. There are several options for three wire operation shown. I have a drill press powered by a Hitachi L100 series inverter. This inverter has no ability to make FWD/REV commands maintained...only momentary. I run a drum switch with OFF/FWD/REV functions and it works perfectly. The FWD and REV commands are simple switch closures of the drum switch. As long as the switch is closed, the drive runs in that direction.

I have TB Woods drives also. They are sophisticated enough to allow you to program a FWD or REV command as momentary or maintained...your Fuji allows this too with the HLD (hold) programming function.

This allows you to run that drive with a FWD/STOP/REV compliment of momentary pushbuttons in lieu of a drum switch if you want.

I'm familiar with 'three wire control' in start/stop applications but don't know if they mean the same thing when used with a frequency drive. On my TB Woods units, the 'three wire' connections are run FWD, run REV and STOP. Each of these commands involves a single wire to the logic terminal buss.

I actually think when they indicate 'three wire' control, they mean momentary contact closures, not maintained. A L100 series Hitachi drive would not have the factory capability for three wire control while your Fuji drive would. Look at the HLD programming function.

This novel has probably confused you more than you were before.

Stuart

Stuart,

Your information was helpful. I can further clarify what I am looking for.

That is, I want to control the forward and reverse functions by use of momentary contacts.

I have seen the HLD feature in the documentation and have tried various function codes to enable it but no success.

If someone knows the correct combination of function codes that would be helpful.

Chuck

Chuck,

Again, I'm not a VFD guru. I think the only way this will work is with three momentary buttons. The FWD and REV buttons are NO and they initiate a command when pushed. That command is programmed in the drive to 'lock in' or HOLD until the REV pushbutton is depressed OR until the STOP button is pushed. That STOP button is a NC contact configuration.

All the functions will be momentary, none will be a switch closure such as your selector would offer. Maybe you have this figured out already. My mill has three 16mm momentary buttons arranged vertically...a FWD/STOP/REV..no maintained buttons at all.

Stuart

Success!

Stuart,

Contacted Fuji via email and they called and left a message.

Soon afterwards, a tech emailed me a .pdf diagram on how to hook up momentary switches to control the motor. It was as you described only the terminals on the VFD were different from what I was playing around with, different function codes.

The manual and instructions were not specific at all and there was no way I could have figured this out if I had only RTFM'ed it.

If anyone needs the diagram, please sent a PM.

Chuck
Burbank, CA

I have a Hitachi L100. I run power directly from the VFD to the motor with no switch inbetween. I use the contacts in the drum switch and three wires to connect to the control input terminals of the VFD. The terminals have to be configured for forward run and reverse run. I power up the VFD then use the drum switch as it normaly would be.

have you tried the manual?

http://www.ctiautomation.net/PDF/FUJI/FUJI-FRENIC-Mini-Drives.pdf

I went through this on the TECO drives I purchased recently. The hard copy
manual had a list of programming codes which included ones for wiring each
drive for the way I wanted to run them (each was different) but there was no
schematic for how to hook things up in the manual.

I puzzled over this for quite some time till I realized, there was a CD rom in the
package.

Yep, the CD rom had a full-up manual which nearly replicated the hard copy.

EXCEPT it had addiional material, including control wiring schematics for each
type of programming type.

One of those, which I did not need to use, was for the three wire setup you
are trying to implement. Basically a NO button to start, a NC button to stop,
and a single pole switch for fwd/reverse.

I urge you to find the most complete manual you can and not rely on a small
printed booklet that may have come with the unit.

Another bug that I found here BTW:

I hooked up my control wiring the way I wanted it, based on the schematics
provided. Then I powered up the unit, anticipating going ahead and programming
the drive to use that wiring.

The drive faulted out and would not run nor would it accept programming.

After an hour of futzing around I realized what was going on - the hardware I had
wired, in the original as-shipped program loaded in the drive, was commanding the
drive to "run" immediately on power-up. This is typically an illegal move (unless
an advanced code is set) so the drive would jam up and go into fault mode.

When I realized this it was a simple matter to disconnect my new control wiring,
restart the drive, program it as desired, and *then* hook up the new control
wiring.

Jim

Dan and Jim,

I do have both the instruction manual and installation guide for my VFD. As mentioned in my earlier post, neither had information regarding the use of momentary contacts only a reference to a hold function. Neither had a wiring diagram for such a setup.

Fortunately a Fuji tech emailed me a jpg of a diagram he had originally hand drawn. There was nothing in either the manual or installation guide that resembled his drawing.

The drive works great now and having quick action switches make the drive a pleasure to use.

Chuck
Burbank, CA

Below is a jpg of the 3 wire diagram and programming notes.



Chuck
Burbank, CA

Rev

Chuck Evans said:

Below is a jpg of the 3 wire diagram and programming notes.

View attachment 204253

Chuck
Burbank, CA

Click to expand...

Hello Chuck,

I realize this thread is a decade old and all, but if yoy see this can you let me know how you wired the Rev portion of the switch. Was is a latching switch that controls direction and Fwd is the equivalent to Run? Or is it a momentary that starts the vfd on it's own?

Thanks.