Hardinge HLV-H Control Circuit

[citizen kane]

I've been playing with the electrics on the Hardinge today. I wanted to check that the control circuit was working OK. The control circuit is 230V AC, this is normally supplied by two of the phase connected to the primary side of a transformer and the 230V comes from the secondary. My initial plan was to disconnect the secondary and wire this directly to a 240V supply. Problem is the 0V on the secondary is tied directly to earth. I swapped the input to the primary to the 220V input just to check things were OK but I was rather hoping to take the transformer out of the circuit. Don't really know enough about these things to know if its wise or safe to remove the link between the 0V on the secondary and earth then feed mains directly into the control circuit, hoping someone on here has done it before or knows enough about these things to help out.

 

[Dcal]

@Pete. the man on these.

 

[Pete.]

That looks like a HLV-H/KL1 wiring diagram, quite a bit different to mine plus it's a bit blurry s o I can't read it properly.

The 0v on the control transformer shouldn't be connected to earth, perhaps it's a CTE isolating transformer and the centre tap is earthed putting the outputs equal amounts above and below for safety. Put up a pic.

 

[citizen kane]

Better picture of the wiring for the transformer and a few of the electrics box.

 

[Pete.]

Ok so they have tied the 0v part of the circuit to earth to stop it floating. If you want to feed that circuit with 240V mains power you can remove the earth connection and run the 0V to Neutral. Make sure it's fused.

 

[citizen kane]

Many thanks Pete.

I was hoping to use the transformer to step up the voltage to 440V to run the speed change motor, any advice would be most welcome.

 

[Pete.]

The speed change motor is 3 phase so you might be able to do that if you can find a 600v capacitor. There is only one motor AFAIK it's just shown twice on the drawing, once for fwd and once for rev. A small VFD might be better, even if the motor can't be re-configured for 240v delta it shoud still have enough oomph to work in star.

 

[citizen kane]

That was my plan for the speed change motor, I think its only 1/20 hp, is there a way of working out what value capacitor to use?

Don't think the speed change motor is easily reconfigured to delta, interesting that it may still work in star from a VFD.

The other motor in the diagram is the coolant pump, luckily that can be easily changed to delta.

 

[citizen kane]

A question about VFD wiring.

I now have three separate VFD's for controlling the Hardinge. Can I common the commons on the multi function inputs on all three or should I keep them isolated.

 

[Brad93]

A question about VFD wiring.

I now have three separate VFD's for controlling the Hardinge. Can I common the commons on the multi function inputs on all three or should I keep them isolated.

keep them isolated as far as i know, but someone else will probably know better

 

[Pete.]

A question about VFD wiring.

I now have three separate VFD's for controlling the Hardinge. Can I common the commons on the multi function inputs on all three or should I keep them isolated.

Keep each one common to the VFD. They might all be tied to earth anyway but why risk ground offsets if you don't need to.

 

[citizen kane]

Thanks.

The generic Chinese VFD's seem to come with very little documentation. Does anyone know if the emergency stop function does something distinctly different to the normal stop function?

 

[Brad93]

Thanks.

The generic Chinese VFD's seem to come with very little documentation. Does anyone know if the emergency stop function does something distinctly different to the normal stop function?

not on the chinese ones no

 

[RichardM]

Thanks.

The generic Chinese VFD's seem to come with very little documentation. Does anyone know if the emergency stop function does something distinctly different to the normal stop function?

Usually coasts to stop and needs a reset to re-start.

 

[citizen kane]

Interesting, sounds like its much better to avoid the E stop and use the normal stop function, at least its brought to a controlled stop.

 

[RichardM]

Yes my "normal" stop is ramp down with the vfd controlling it (no braking resistor) and restart when "go" switch pressed. E stop is coasting with no power to drive until it's reset.

 

[Pete.]

e-stop on my mill is a fast stop via the controls. I can't think of any incidence where it's been necessary to kill all of the power to the drive/machine, so e-stop is on the control circuit. If you're gonna use it, it's much more likely to be something that YOU have done wrong when using it.

 

[RichardM]

My stop switches are all set to decell stop Coasting stop is the other programming option if you don't choose decell.

 

[citizen kane]

Eventually got all the VFD's fitted and wired up to a combination of the existing cam switches and contactors. Need to tidy the wiring up a bit and document it all before I forget how it works.6

 

[citizen kane]

Looking to get some cutting oil for the lathe. Experience suggests I wont use it wet that often, any recommendations or should I just put some cheap hydraulic oil in the tank.