Renovating a Hardinge HLV-H

[BillTodd]

Applied power to the thing for the first time.

First I rewired the control transformer to accept 240v input (instead of 440) then checked the contactors were operating OK.

Checked the power feed controls - they were working OK, except I'd reversed the connections to the variable transformer so high speed was low and vice-versa (easily fixed).

I then bodged* my 440v VFD on, temporarily using the control transformer as a step-up. Got the spindle spining in both high and low speed and up & down the speed range.

But, while doing all this, I noticed the slow-start resister on the VFD was smoking (It's an old 5HP Toshiba device and has a softstart to prevent fuses popping on switch on). I powered down to investigate why the relay, which bypasses the resister, was not working. I had to take the VFD apart to find out why (I have no manual for this thing). I stuck it back together only to get no responce at all. I then realised I'd forgotten to replace the current limit lead (which has to be removed to get at the relay).

It popped a 600v 20A fuse and killed one of the IGBT modules :(
( a MG50M2CK1, if you have any in your pockets)

BTW Mike:

I found a couple of subtle differences between my machine and the wiring diagram from your site:

The spindle interlock contactor is wired in a different place it disconnects the 3ph only to the motor and the 1ph control power to the up/down contactors

A couple of spare contacts on the fwd/reverse switch are used to break the main contactor coil circuit - so if the fwd/rev switch is changed while running it stops the machine.

I'll draw a diagram of it for your site if you wish.


*(I do this sort of thing for a living, so by bodged, I do not mean unsafe)

[aafradio]

BTW Mike:
I found a couple of subtle differences between my machine and the wiring diagram from your site.
I'll draw a diagram of it for your site if you wish.

I'm not surprised. That's one of the reasons that they have a pocket in the electrical door - to hold the as-built condition of the machine when it went out the door of the factory. That condition does change over time, usually in minor ways. I've also noticed occasional cultural differences in wiring design between the US and European models, mostly related to safety practices on each side of the pond.

I'd be delighted to put it up on the aafradio site as another variation if you'd like to e-mail it to me. Never can tell who it might help in the future.