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Hardinge HLV-H-EM Power Supply

Dec 24, 2022
Hi all,

I'm relatively new to manual machining and even newer to electrical controls/ circuits, so I'd like to apologize for my incompetence in advance of this inquiry.

I am trying to figure out the power supply for my first Hardinge machine - a mid-'90s HLV-H-EM. Unfortunately, there is no wiring diagram for the machine and the previous owner has passed away. I reached out to Hardinge Service, but I'm hoping that someone here might provide some information about the main drive motor and controls. The nameplate indicates the machine requires 208 V Supply for the 1.0 HP motor. After further inspection though, it seems the original spindle motor was replaced with a Pacemaker Motor which lists the voltage as 230/460 and the horsepower as 1.5 (pictures attached).

Is this discrepancy between the machine supply volts and the motor supply volts standard? Put differently - does the control cabinet include the necessary components to safely supply the motor with 230V (without risk of overheating) if the machine is being fed 208V? machine name plate.jpgmotor name plate.jpg
Sorry to de-rate your machine motor on the first reply...

"H.P. 1/.5" means 1 HP at 208V and 0.5 HP at 460V.
Opinion is that you don't have an issue. As long as the motor is wired for low volts and 1675 RPM.

The machine tag stamp for "208" meant something from a previous relationship.
Look inside the cabinet and locate a coil from a relay or contact. Will most probably be 220 or 230.
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"H.P. 1/.5" means 1 HP at 208V and 0.5 HP at 460V."

Doubtful. It's a two speed motor. 1675/520 rpm. 1 hp high speed , 1/4 hp low speed.

This is either a dual winding motor or a dual voltage consequent pole motor, probably 12 leads if the latter.
Doubtful. It's a two speed motor. 1675/520 rpm. 1 hp high speed , 1/4 hp low speed.
I believe Jim R has it right, though probably meant to type 1/2 hp low speed.

Could this actually be the OEM supplied motor? That does not explain the discrepancy between the supplied voltage and motor voltage but several other specs are consistent with OEM supplied motors. My experience is with older Hardinge machines, but the two speed RPMs, HP/RPM ratios, amperages and special balancing are consistent with Hardinge supplied motors. Likely would have been very hard to find an off-the-shelf motor of those specs, as well as very expensive, to solve for the difference between 208 and 230 supplied voltages.
I think the motor is correct for a Hardinge lathe because the balance and noise ratings indicate a premium class motor typical of what Hardinge would install. Further, the 1800/600 RPM synchronous speeds of the two-speed motor are correct for that model lathe (3:1 speed ratio). My 1960 Hardinge has a similar rating motor made in my city by GE.

A 230 V rated motor will operate on 208 V. I found a Magnetek Pacemaker 1 HP motor on eBay that is rated 230/460 V but also mentions 208 V on the nameplate. I agree that it would be a good idea to verify the starter coil voltages (should be 115 V) and the control transformer connections (might be 208 instead of 230 V) to see if they are suited to the owner's supply voltage.

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I have the correct manual and wiring diagram for your lathe. Note on the electrical dataplate that your lathe calls out for wiring diagram CKB-0008220-L. In the attached pdf id wiring diagram CKC-0008220L, I believe that should be close enough for your purposes.


  • New Electrical Schematics from Hardinge.pdf
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"probably meant to type 1/2 hp low speed."

Damn old age is setting in!

Concur it's probably OEM, but has to be dual winding type with that speed difference.
Thanks for all the help, fellas! I think I've got it sorted out. For those interested, here's my current understanding of the motor/ electrical controls and my plan for power supply to the machine:

The motor is almost certainly original, and the machine is currently wired up for a 3-phase input at 208V. The previous owner had 208V 3-phase service to his garage shop; unfortunately, my garage is stuck with 240V single-phase.

Notes in the wiring diagram seem to suggest I can simply disconnect the autotransformer (pictured below) and supply 230V 3-phase to power the machine without issue. My other two machines require 230V 3-phase input, so I feel like the simplest solution would be to disconnect the autotransformer and install a digital phase converter that is capable of supplying power to all three machines.

Am I way off on this?


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The nameplate people were nice enough to specify the type of grease.
How would they know that Chevron would stay in business. :drink:
I take that to mean the autotransformer is only used with a 208 V supply, as marg stated in post #11.

I read that exactly as stated. Only use the 208 V because the wiring to the transformer is configured for 208.
Reconnect the internals for 230 V. And then re-stamp the nameplate.