Home Forums Hunting & Shooting Hunter's Campfire Lectricians, phase conveter?

I ran a Bridgeport a few years ago with a generic static phase converter on it & it seemed to run great. If I were to buy a mill for home use I'd go that way & as has been said, I'd buy another If I were to add a lathe.
Plans of more machines or high usage, I then might go rotary.

If you can find a model number on your VFD, you should be able to look up the specs and figure out what its capable of. In general, they can all run on single phase, but have to be derated somewhat. A VFD internally rectifies the input AC to DC and then electronically creates AC while controlling the output current, voltage, and frequency. The derating is necessary because a three phase bridge rectifier shares the current among more diodes than a single phase rectifier does. If the VFD you have is designed to run on 460V instead of 220 then you are out of luck and it will have to be removed. In that case your motor would also be set up to run on 460 and would have to be re-tapped to the lower voltage.

A good VFD will be more efficient than a rotary converter and gives you the benefit of variable speed. You can even overspeed a motor as long as you don't exceed the power rating.


Jerry

I’ll try to take some pictures in a bit and post them and maybe you guys can tell me what I have. The machine retains its drum switch and the J heads are a step pulley so no variable speed adjustment hand wheel. I have videos of it running that the guy sent me before I bought it but I don’t know how to post a video.

I would have been happy enough with just a plain old step pulley mill setup but since it came with the VFD I guess I may as well use it. If it turns out I can’t figure out how to power it on the cheap I’ll pony up for a new VFDI guess. I’d just like to get it up and running to generate some quick cash doing some odds and ends piecework.

Photos are alway helpful for getting familiar with a project.
That big breaker box you mention with the kill switch on it (disconnect) could easily have a motor contractor in it.

If you are going to post images, get images of the ID plate on the side of your current VFD. Be sure the make and model and any other written data are readable.

There should also be a data plate or maybe two on the motor, get readable images of those.
It wouldn't hurt to open the wire box aka "peckerhead" on the motor and take a photo of that as well.
You should find a small rats nest of wire in there, spread them out a little for the photo. If you see a little sticker on the inside cover of the peckerhead that looks like little lines and numbers, include a photo of that also.

Tag

Okay so here’s what I found after I managed to get the boxes open for a peek inside. Appears to me that the VFD needs 3ph and the smaller box is sort of a remote for lack of a better word.

I’ve looked at the static converters that can be had cheaply, $75 or so. But the fact that it would derate my motor that’s already only a 1hp scares me. I’ve never run any machine and said to myself “I wish I had less power” but I’ve said the opposite on many occasions.

https://www.24hourcampfire.com/ubbt...eries/12729158/electric-gadgets#comments

I’m sorry I can’t seem to figure out the image posting deal since the change

Humm.

Well, it's a remote for sure. Musta been handier for him than using the controls on the drive.
Sure added a lot of wire to the job though.
If you buy a new drive and want to keep the remote, you'll have a good bit more wire to land.

It's actually a nice set-up but for the life of me I don't know what he is using the Rino 24v power supply for thats installed beside the drive.. The drive is 24/10v dc controlled but it should create it's own dc control power. I'd love to see where he landed that red and white wire that disappears behind the cover on the drive.

Without the data info on the drive there is still some guessing.
If you were to take more pictures pop that top and bottom cover off the front of the drive so we can see the wire up. Open the remote box for a photo too so we can see the control wire up thats been done.

A 7 1/2 hp drive for a one hp motor isn't alway a good thing. I've had some that would not allow me to dial the max amps down low enough for suitable motor protection on a way smaller motor without going into fault.

We'll assume the motor is wired for 230v service since the drive is 230v but I always like to open the pecker head to check and make sure, but thats up to you.

Jerryv sounds like a pretty sharp guy, he said ANY VFD could run off single phase input. I've never done that. The de-rating he spoke of I took as you would have to de-rate the drive, if thats the case your in good shape with the 7 1/2hp drive.

It'd be worth waiting him out and giving it a try, not having any experience doing that I would be guessing at how to wire it up. but if it works you're home free.

Go download this users manual

https://cdn.automationdirect.com/static/manuals/gs2m/gs2m.pdf

As long as you own the drive you might as well own the users manual........

It's only 190 pages of mind boggling schit...:-)
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Now, an hour after I made this post, I've read the manual..

Looks like your drive is probably a GS2-27P5
This manual covers over a dozen different models.

It's going to suck of you can't use this drive, it's a good one
and the manual is rather straight forward and written in a form
that makes it pretty easy to find the data you'll need.
I'm keeping my fingers crossed that Jerryv is able to walk you
through the wire-up but I'm not liking what I am reading about
your particular model drive and single phase input.

I've used a 3 phase drive with a single phase input more that once with no issue. Here is a pretty good reference for derating.

http://www.dartcontrols.com/wp-content/uploads/2012/01/De-Rating-VFD-for-Single-Phase-Power.pdf

Your motor nameplate is 3.3 amps at 230 volts.
Using the derate value of 1.73 x 3.3 amps gives you a new amperage protection max of 5.709....lets call it 6 amps....looks doable with a single phase source

Great info, very helpful.

I've never been in the situation to need to consider this as an option.
Always been in industrial environments where 3 phase 480v is normal and every job spec'ed out to precise detail.

Quite impressed with the knowledge base on this topic here at the Fire...
That being said, I'm going to throw down with what I think he needs to do, anyone seeing error in my ways please chime in, I don't claim to know it all.

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First off, it appears your drive will be rated suitably for the job, lucky you this guy put a 7.5 hp drive in to run a 1 hp motor.
Your incoming power from your shops source is going to connect to the breaker in the top right hand corner of the box your drive is in.
The breaker is 3 pole for 3 phase application, you are just going to connect 2 wires to it. Connect them to L1 and L2.

On the bottom of that breaker there are five wires. Three red and two black.
Remove the red wire from T3 (the far right hand tap) and chase it to the drive and remove it from there also.
It "should be" connected to L3 on the drive when you go to remove it.

Now the smaller black wire that is currently connected to T3 on the Breaker needs to be moved to T1 on the Breaker. This is what he is powering the Rino 24v power supply with. I don't know what it does but it doesn't matter, just connect it .

Now you should have two red wires leaving the bottom of your breaker (T1 and T2) that connect to L1 and L2 on your drive and no wire in L3. The two small black wires also connected to T1 and T2 on your breaker that connect to the Rino 24v power supply.

If that's how it looks, you're ready to throw the switch and see what happens. I would remove the belt so you are just turning the motor and not the machine for the test run.....

Don't be too surprised if the drive goes into a fault. You might have to tweak a parameter or two due to the de-rating of the drive. I just don't want to get into that part if you don't have to. It should be good to go the way the guy was running it..

You have the manual with all the fault codes and parameter setting explained so it's no big deal if you have the need.

It looks like they were running 230v three phase input and using two legs of that to run through a control circuit breaker and feed a 24v dc control power supply (the Rhino). If you do try to run this from single phase to keep the same setup as before you would need to make sure you were feeding the power supply from the same two legs as your input power then the existing control they were using before should work without any changes. If what I am seeing in the pic is truly this way bring in your single phase legs to L1 and L2 terminals at the top of your disconnect switch. Move the black wire on T3 terminal (bottom of disconnect switch) to T1 (bottom of disconnect switch). If what I am seeing is correct you should be able to power up at this point and check voltages before trying to run the drive. Make sure the toggle switch is in the OFF position. If the drive upon power up does not fault when applying single phase power this may work out for you....

Oops you beat me to it....

I am an industrial electrician myself. A couple or our remotes sights only have single phase. I've been forced to go this route after our engineers just assume everyplace has 480.

I have tried all the routes myself. Right now I am running an Anderson RPC. I had a static one for a mill and it cut the power significantly and ultimately burned up the motor. I converted another Bridgeport to a DC motor with a variable drive on it- I have 2 this way now. My bigger lathe has the RPC which is 10 hp and the lathe is 6 hp.

My one attempt at using a VFD made smoke and no worky so I gave up on that idea. A 10 hp 3phase motor will work for what you want but will use more power than is needed and therefore not as efficient.

I wish I could get 3 phase to my shop for $1600!!

Yep, ya gotta keep the smoke inside if ya want it to run, it's an electrical requirement.

Guys thanks for all the help. I’m going to see if I can get a friend to come over and see if we can get this thing going here soon. If he sees something wrong or it doesn’t power up like it should I will probably go ahead and put together a RPC since it would be nearly free since I got all the motors for free.

The two 3ph motors are Baldors my Grandad had as spares when he owned the grain elevator here in town. They’re brand new but he sold the elevator in 79 or 80 so they’ve been sitting a while. They don’t go bad, do they?

If they have been setting that long spin them by hand and listen to the bearings for noise. They can just set there and rust all to hell.

I'd get the motors in a very dry environment for an extended period of time, again due to possible dampness in the windings. 40 years of sitting around could have resulted in the windings getting damp and just corroding away.

Have the faith in the VFD, you'll be way ahead if it works out and at this point I don't see any real reason it shouldn't.

I agree with others that it is odd to have a 7.5hp unit on a 1 hp motor, but if it worked before, it should still work. Since it is so oversize, it should have no problem with single phase unless it is set up to detect a missing leg. I also am puzzled like others on the purpose of the 24VDC supply. Looking at the manual a little, it doesn't look like it should be needed for the VFD. Perhaps it is intended for something else. Without seeing the rest of the wiring, there is no way of telling. Pictures of the VFD with the top and bottom terminal covers off might help. It looks like the power comes in the top and goes to the motor from the bottom, but there are other inputs and outputs that also have terminals under the bottom cover.

One thing I would recommend is that you scroll through the parameters and write them down. If you should ever need to replace it or send it in for repair, you will need to reload them and it could save a lot of time and aggravation. BTDT.

Jerry

Them gasoline cars will never catch on, steam is where it is at