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JohnAXA
1st Aug 2016, 02:13 AM
Hello to all, and hopefully one of you Lads can provide advice... I have a 3 phase Milling machine and want to run it off a single phase supply. It has a 1.5 HP motor on it.

I need to know the best way to jump.

Kind Regards, John

Vernonv
1st Aug 2016, 08:19 AM
If only one motor, probably a VFD would be "easiest". Other options are a static or rotary phase converter, or even a single phase motor swap.

jackaroo
1st Aug 2016, 09:31 AM
Hi John,

I am using this unit and it seems ok. The extra knob on the control pad for frequency control is nice. Search for "VFD" in the forum, there are a few threads
1500W 2HP 240V 7A Single Three Phase Variable Frequency Drive Inverter VFD | eBay (http://www.ebay.com.au/itm/1500W-2Hp-240V-7A-Single-Three-phase-Variable-Frequency-Drive-Inverter-VFD-/391515687942?hash=item5b28274c06:g:fc0AAMXQHU1RsC8j)

tanii51
1st Aug 2016, 09:40 AM
If you go the vfd way make sure you can configure the motor to delta depending on which motor some just need to have the jumpers changed ive just converted a Tom Senior mill which didnt have jumpers but with a bit of careful study it wasnt too hard to find the star point junction and change it.If your not too sure i suggest a motor rewinder or sparky should be consulted
John

Oldneweng
1st Aug 2016, 12:48 PM
It would be useful if you could post pictures of the motor data plate and the motor connector block. There may be a diagram of the motor connections under the cover of the motor connection block as well.

Dean

jhovel
1st Aug 2016, 10:50 PM
I agree with Dean: Show us the motor and we'll help you avoid some traps.
Also, the $150 VFD jackaroo pointed out to you is the better choice over the lower cost ones currently on eBay. It is a Huanyang and lots of people here have them and have gathered lots of experience with them (including me). The lower cost current crop isaninferior product with minimal settings only. I got 'trapped' by the price andthe very similar look of them.They are significantly different to the Huanyangs.
You other alternative is to contact Chris Parks by PM (a member on this forum) who can source a Powtron VFD which is a bit better still.

JohnAXA
13th Aug 2016, 12:17 AM
Hi Lads, Thanks for the replies... I have been a bit off colour lately and have not had a chance to reply. I have taken a few pictures and will post them when I get over this minor OP this coming Monday. I seem to take a lot longer to do anything these days, bugger to be getting Old.

John

KBs PensNmore
13th Aug 2016, 01:44 PM
Get well soon, John:2tsup:

Ryan in Melbour
14th Aug 2016, 09:22 AM
http://metalworkforums.com/f303/t198582-lathes-dummies-resurrection-sheraton-cub-600-a/page-5

posts 4 thought to 10 is me rambling through the same problem!
good luck

JohnAXA
14th Aug 2016, 04:38 PM
Having trouble getting around sending a couple of pictures... I'll try with this message...NO Luck

Oldneweng
14th Aug 2016, 09:28 PM
Try looking at this post

http://metalworkforums.com/f36/t168803-uploading-photos-attachments

Dean






(http://metalworkforums.com/f36/t168803-uploading-photos-attachments)

JohnAXA
16th Aug 2016, 11:08 AM
Well I think I have attached two photo's containing the needed info, and thanks to Dean for pointing me in the right direction. I hope that it will provide enough to enable a solution to my problem. And, I only need the
device for one motor. no info inside the cover.

I do have a three phase motor and controller on a VICMARC VL-300 wood lathe but it was all setup when I bought it many years ago. I did make a four foot extension to enable me to turn stuff up to
eight feet long. My brother wanted me to turn the posts for a 4 poster bed he wanted, out of cedar and that was the reason for the extension. The lathe is able to run from about 30 to 3000 revolutions per minute at
the turn of the Pot...

John

Vernonv
16th Aug 2016, 12:21 PM
If I'm reading that right, it's a 2 speed motor ... not 100% sure, but I don't think you can run them off a VFD (or at the very least you will lose the dual speed facility)

BobL
16th Aug 2016, 12:41 PM
That is indeed a 2 speed (Dahlander, ∆/2Y) motor.

It is wired for 415V only.

On either speed (even the ∆ config) it will only run at half power on 240V 3P.

It can be rewired internally only for the 2Y side, converting it to a 2∆ which will develop full power at 240V 3P.
I don't think motor rewinders would approve of this and it would be better and not much more expensive to buy a new dedicated 240V 3P motor.

Oldneweng
16th Aug 2016, 12:51 PM
Does the mill have 2 speed settings?

It seems the motor is Delta/YY. Normally you would find which connections were the Delta ones. This would be the black wires labelled with either 1UVW or 2UVW. These delta connections would be connected to the output of the VFD.

Delta will give 1480rpm and YY will give 2850rpm if I am reading that plate correctly.

Dean

Oldneweng
16th Aug 2016, 01:02 PM
Bob beat me and he knows far more than I do.

Bob what tells you that this is different to a normal Delta/YY motor?

Dean

BobL
16th Aug 2016, 01:57 PM
Bob beat me and he knows far more than I do.

Bob what tells you that this is different to a normal Delta/YY motor?

Isn't that what I said it is?

JohnAXA
16th Aug 2016, 03:27 PM
Hi Dean. I have included another photo of the face of the machine with the other 2 pics, and I think it has a switch for 2 speeds... not sure as I have not had it running but it has been tested on 3 phase.

John

BobL
16th Aug 2016, 08:38 PM
In this thread there is some info on a ∆∆/Y motor I jiggered to run on 240 3P
WIring arrangements on a ∆∆/Y motor (http://www.woodworkforums.com/f271/wiring-arrangements-motor-183910)

Now Here's what the ∆/YY looks like
363903

The LHS delta is usually set up for 415V, The RHS can be converted to run on 240 3P by breaking open common point C and the connecting as follows.
I would class the conversion a RRPITA (Right Royal PITA)


363904

My Large Finisher/Belt sander has been converted like this and its been running well between 10 and 60Hz.

Oldneweng
16th Aug 2016, 09:04 PM
Isn't that what I said it is?

I was asking you a question, but don't worry about it I have it figured.

Dean

Oldneweng
16th Aug 2016, 09:08 PM
If I'm reading that right, it's a 2 speed motor ... not 100% sure, but I don't think you can run them off a VFD (or at the very least you will lose the dual speed facility)

That depends on the motor. My lathe has a ∆/2Y motor and it is set up to run at both speeds which have been checked with a tacho to be correct.

Dean