Yet another VFD question

alloy

Dan, Retired old fart
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I picked up a 1962 Bridgeport last week and I want to power it with a VFD. At work we have belt sanders that use a Genesis VFD to run a 3 phase motor. These things get turned on and off well over 100 times per day, and for the last 5 years I've been there they work perfectly.

Ideally I'd like a rotary on-off-reverse switch like the one that's already on the mill, the potentiometer, and a jog switch remotely mounted with the VFD mounted on the all behind the mill.

I talked to Carl at Electric Motor Wholesale and he recommended this unit. But he doesn't recommend using remote controls unless you really know what your doing to connect the unit properly. And that's the problem, I know nothing about electronics. I can build you any helicopter part you need, just not read and understand an electrical diagram.

He recommends mounting the unit on the side of the mill, but this isn't a small unit. And I don't really like drilling holes in my 52 year old housing to mount it. And I guess I'm old school, I would like the traditional style on, off, reverse switch.

I guess what I'm asking is there a plug and play setup with what I need available somewhere? I'm pretty much on overload reading about VFD's and the more I read the more confused I get.

Any help would be greatly appreciated.


http://www.electricmotorwholesale.com/9520-KBAC-27D/

Here is my thread about buying and cleaning my mill up.

http://www.hobby-machinist.com/showthread.php?t=24097&p=213609#post213609
 
I mounted my VFD on the wall & ran a shielded cable to a box on the machine with forward & reverse toggle switches & a potentiometer. The Jog switch is unnecessary in MHO .... just use the pot. My box mounts to a heavy aluminum angle that is in turn mounted to my 45 year old housing. It's in an instantly available position from in front or on the left side of machine a little lower than head-height.
Instead of the two toggle switches you may be able to mount a small box onto original switch housing for the pot. Don't be afraid of remote controls ... just a simple wiring job. I would not recommend placing controls where they can't be easily reached from your operating position.
 
Looked at the manual online; wiring up remote controls is pretty well illustrated starting on page 28. I prefer start button, stop button, speed potentiometer and fwd/reverse switch but several options are shown in the manual. Not sure why the salesman is warning about wiring, if you can't handle the diagrams, probably need an electrician to install the VFD.

Do you really need the NEMA 4X enclosure? (it adds quite a bit of cost) I have a VFD mounted on the wall above my metal lathe, no enclosure (it is in a fully enclosed building). Wood lathes commonly have the VFD mounted behind the headstock without an enclosure. If you don't use an enclosure, mount the VFD high enough that metal chips will not fall into the vent openings.
 
I installed the Hitachi WJ200 and posted about the process here ;http://www.hobby-machinist.com/showthread.php?t=22701&highlight=WJ200+hitachi

I think it's not that difficult to wire up w/ the rotary and/or anything else you wish. We're here to help. The hitachi is a really cool unit with a lot of feature / functionality. But it is not in a washdown enclosure.

you're unit will run up to a 6HP motor and that's a good clip! What size motor will you be running? On your power, did you say if you have three phase or two phase? I have two phase and needed the unit that will convert from 2 phase to 3 phase motor output.

I also found this sticky here about VFD . http://www.hobby-machinist.com/showthread.php?t=55&highlight=WJ200+hitachi

Enjoy!
CG.
 
Thanks for your reply. The first thing is I really don't know what shielded cable is. I'm a CNC guy and a pretty fair backyard mechanic, but that's as far as it goes. I did wire my old shop for 3 phase, but that was simple. Two 110v lines and the 3rd wild leg line. Simple to figure out even for me.

I thought about taking the switches out of the box and mounting them on the head in a small box if I can find one I like, or I'll just make one. I did see on the description of the VFD is says.............*Warning! It is highly recommended that the Signal Isolator (Part No. 9600) be installed when using the drive with external control signals. Do I need this if I move the switches from the VFD to a remote box?

I found this pic somewhere, not sure where. But this is ideally what I would like to have. The tach would be nice, but not necessary. I can grab a laser tach off ebay for $20 that will do the same thing.

IMG_2698.JPG

IMG_2698.JPG
 
I agree with the rest of the guys here. Putting remote control switches on a VFD is pretty straightforward. When I did my VFD builds for my mill and lathe, I documented the build somewhat and made some videos that might help. Here is the thread with a bit of a build log; the videos are at the end of the thread: http://www.hobby-machinist.com/showthread.php?t=17670
 
I did see your thread with the box, very Nice work. Way over my head.

I can see how it wouldn't be too hard to extend the wires to move the switches, but would that create any problems?

And the guy from wholesale said there are literally dozens of style of rotary switches and I would need to look at the manual and find one that would work with the VFD.

I don't really need the enclosure, my reason for looking at this particular VFD was all the abuse it takes at work and keep on going day after day, year after year. I'd rather spend a little more now, than have to buy it twice.

My motor is a 1hp 4.2 amps. And it's a 1962 so not as efficient and a newer motor I'm told.

I did read the sticky about installing a VFD. The power wiring is very simple. It' just the remotes and specifically the rotary switch that I'm not clear on.
 
I did see on the description of the VFD is says.............*Warning! It is highly recommended that the Signal Isolator (Part No. 9600) be installed when using the drive with external control signals. Do I need this if I move the switches from the VFD to a remote

Ive never used a KB AC drive but I've installed plenty of their DC drives, and im betting the reason they recommend this is that their AC drive suffers from the same half-ass design as the DC model; that is, instead of taking the "extra" step of including an isolated internal DC supply (only a few extra componencomponents, apparently too expensive), they leave the internal DC supply floating at mains potential. What this means is, you put your DMM and DC mode and measure across the speed pot: "oh, cool 10v, exactly what it's supposed to be. Should be safe to grab the pot from the back and hold it while I tighten the front nut..." NOPE. There is "only" 10VDC across the pot, but this 10VDC is riding 100+VAC above ground. So you shock the **** out of yourself and then go warn others on the machinist forum.

KB makes a good inexpensive DC drive and I will buy and use and recommend them in the future, but you must realize it's a bottom of the barrel device with corners cut to make it affordable. Don't trust it with your life.
 
Well I'm pretty much sold on the Hitachi drive unit. I found one on Ebay for $219 shipped.

So now if possible can anyone give me some suggestions on a rotary on-off-reverse switch, and a speed control knob? I've found several rotary switches on ebay, but not sure exactly what type is needed.

This one is in the US so it won't take forever to get here. Just not sure if it will work with the drive.

And thanks everyone for the help your giving me.

http://www.ebay.com/itm/121004145870?_trksid=p2055119.m1438.l2649&ssPageName=STRK:MEBIDX:IT
 
Hitachi is a good drive. They actually make units for other famous brands who just brand lable them. Square D/Tele, Allan Bradley, Rockwell are three for sure. The big boys do not like fooling with these little drives for a $50 profit when their people can work on 500HP and 1000HP drives and they can put some real money in the Corporate account.

Most any $15 22mm three position selector switch will do the job. On-OFF-On is a standard switch code anyone can supply. Ask for an extended handle switch, they are the same cost and sure are a lot handier to use. The wiring you connect to in a drive is all low voltage to terminals. #18 guage multiconductor cable will get the job done. I set my BP up with a three position spring return to center selector switch and a large mushroom head stop button. I have been very happy with set up. I found jog to be unnessary as you can just grab the spindle and turn to any position you desire. Probably why BP does not install them from the start.

On to mounting the drive. I made a back plate and mounted the drive behind the door in the column. Nothing in there anyway. Then I mounted water tite boxes on the right hand side to get places to power up 120v devices. DRO, coolant pump, work light, and such. My mill has the built in vari-drive so I only use the drive for making 3phase, and motor protection. No speed control.

If your drive is the open type please mount it in something. The airborn swarf from machinging, welding and grinding is a lot thicker than you may suspect. This seeming light dust is very conductive and will wipe out a drive or any electronic device in one quick pop. At least get a conduit adaptor box for the drive so you do not have all the wires hanging out of the bottom of the drive. This will allow you to properly terminate cords, cables, flex and conduits. Go beyond the counter man helper if you have to as most people do not know these attachments exist.

Good luck you will love it when you are done. It is not complicated and I would be happy to help answer questions that may arrise. Now get back to work so you can start piling up that SWARF!
 
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