Advice for powering up a Hardinge HLV-H 440 Volt

I am sure there is information on this somewhere but I'm not sure on the specifics. So here is my question.

I just picked up a Hardinge HLV-H lathe that is setup for 440 V 3 PH. I have a 20 HP RPC that feeds my three phase panel with the maufactured 3rd PH at 220v or just under. What is the best way to get power at the correct voltage and Amp to this lathe.
I heard that I could come right off the single phase panel into a single phase 240/480 step up transformer then into a VSD with a 3 PH output, but this may be a problem with the 2 speed motor. Another option would be to use a 3 PH 240/480 stepup transformer after the 220 3 PH panel and go directly into the lathe. This will power all the motors (coolant,varidrive,feed) and allow switching speeds and reverse without any problems, you just need to make sure the manufactured leg is on the correct motor starting leg.
Any suggetions or comments, also a little confused over 240/480 stepup transformers when I have 220 volt at the panel and the machine is looking for 440V.

I have only a few minutes to reply so here is the short version.

I looked into the problem when I was trying to buy a HLVH. I concluded the easiest way is to use a single phase transformer to step up to 480 volts then feed this into a 460 volt VFD. The VFD will need to be a 3 phase input-3 phase output and will need to be rated for twice the motor horsepower due to you operating it on single phase input. The VFD will also need to be one that will operate from single phase power and many of them will, espicially the Asian models. You would connect the VFD directly to the motor's high speed windings and bypass any of the orginal switches/ starters. You can connect the orgianal switches to CONTROL the VFD so it will operate as it did orginally.
When you set the VFD for 50% speed (30 hz) you functionally be the same as the orginal low speed. I think I remember the motor is a constant torque design with the high speed hp being twice the low speed hp.
AT 100% speed you operate as the orginal high speed and at 50% speed you will operate the same as the orginal low speed.

I hope all this is a clear as mud. I have been using this setup on a two speed geared head drill press for a number of years so I know it works.

Bruce Norton
Kingsport, Tn

Having done this a number of years ago, all I did was take the 3-phase 220vac output from the RPC and feed it into a transformer. I actually used the windings backward, as the transformer was designed to take 440vac to 220vac. The transformer was vastly over-rated for what I was doing, but I only paid about $75 for it. The transformer is sitting at a friend house in Cincinnati and it weighs a lot (200lbs?). It got moisture inside it from condensation while stored in an old "box truck". It is probably OK and could be acquired for basically scrap value. No help in moving or shipping though.

The problem with using a vfd, is all the control reworking you have to do, and then the levers and features are not as designed. One transformer and your HLV-H will never know the difference.

Another alternative is using a single phase transformer to boost the voltage and then build a 440vac RPC. Seems like a lot of work for nothing, if you already are using a RPC for other machines.

JC has the best approach as far as running your lathe as designed - if you want to fart around changing all the control wiring - there are advantages to going VFD - but if someone has to explain it in painstaking detail . . . go with JC's advice.

There is an additional possibility not yet mentioned. When I was trying to buy a HLVH, I called a local motor repair shop and inquired about rewinding the motor from 440 to 220. This was about 5 years ago and the estimated price was $350. I am sure rewinding costs are higher now due to the increase in copper prices but it may still be a good option. It will be more costly than installing a 240 to 480 transformer (assuming you get a used transformer). It will be less costly than buying a new transformer.

toolnut said:

There is an additional possibility not yet mentioned. When I was trying to buy a HLVH, I called a local motor repair shop and inquired about rewinding the motor from 440 to 220. This was about 5 years ago and the estimated price was $350. I am sure rewinding costs are higher now due to the increase in copper prices but it may still be a good option. It will be more costly than installing a 240 to 480 transformer (assuming you get a used transformer). It will be less costly than buying a new transformer.

Click to expand...

Did they rebalance the motor? (as supplied the HLV-H's motor is balanced to 0.0003" peak-peak)

An RPC is probably the simlest solution if you're running more than one 3ph machine. However, once converted to VFD the lathe has a greater resale value (bigger market) and will generally run sweet as a nut .

Complicated conversion here: Renovating a Hardinge HLV-H

Bill (a VFD fan )

Good Advice!! from all thanks
ARCO Roto Phase gave me some specifics on a General Purpose transformer and Acme did the math.
What I am now looking for is a 3KVA 3 Phase Delta 240/440 General Purpose Transformer with taps.
So far no luck on Ebay and this will run about $800 if purchased new.

Even though the VFD would make the lathe more marketable, I have no intention of reselling this Dream lathe, I like the Transformer it's simple and will get me up and running quickly.

Thanks again for all your ideas,

Thanks Jim
I picking up an Acme T-2A-533281S Transformer from my Rep. @ Grainger for $550.00. Catalog price is around $800, not a bad deal considering the prices out on the internet for new. The transformer is a 3Kva 3 phase Deta in Delta out 240/480 General Purpose transformer with taps for 480,456,432 V.

There is no need to rebalance the motor after a rewind because the work is all on the stator and the armature is unchanged.

A 3 phase transformer is better, but you can use single phase transformers as well. In fact, you can use two in open delta rather than three, but considering that the manufactured leg is not all that stable to begin with, that could have problems.

About a year ago there was mention on an English site of a 220V input (1P or 3P)
and 440V/3P output VFD. My research, now evaporated on the winds of time,
suggested an FOB price from England in the $550 or so range. This was apparently
a Continental approach to the HSM problem of 115V/1P ->220V/3P VFD for low
power motors. Haven't seen a 220-> 440 VFD on sites in the US, however.

Go convince Ferrous Antiquos to actually part out the UM milling machine he has,
and buy the 240 volt motor which is the exact part you would need. Get him
to sell me the drum switches too!