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Hardinge HLV-H Electrical

racingjason

Plastic
Joined
Jun 25, 2017
HLV-H - using VFD strictly to produce 3-phase?

Hello all,

Please forgive me bringing up this subject again; I have read all the posts that I can find about the subject of single/three phase/dc/vfd's/phase converters on this lathe and what I have realized is that I may not (probably don't) understand how the HLV-H's are designed. I am presently looking at what seems to be a decent used example that is 220v. My plan was to buy a similar VFD to the one I use on my Millrite MVN (https://cdn.automationdirect.com/static/specs/gs2drive.pdf) but since the lathe has variable speed already, just set the VFD to 60 HZ and then leave it alone. (Similarly I could look for a digital phase converter to take switch from 230v to 220v 3-phase) My assumption was that the three phase power fed into the HLV-H was transformed/inverted within the electrical panel to run the accessory single phase and dc motors. Is this correct?

Many people are quite adamant that a VFD is a bad idea on the HLV-H. Now I understand that running at a lower/higher frequency will mess with the accessory motors but could I used the VFD simply as a digital phase converter? I realize it does not take advantage of all the benefits of a VFD but in this case I just want a simple unobtrusive way to run the lathe.

Thank you,
Jason Porter
 
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I think what he wants to do is to use the VFD strictly to produce three phase power, nothing else, what is the old days was called a drive. The problem is that switching motors and such on the output side of a VFD is not a good idea. Better to get a small rotory and leave the lathe alone.

Tom
 
Thanks JR, I have updated the title as recommended.

Tom is correct about what I was thinking about doing. I will look into a rotary more closely; I was avoiding them for space considerations. Thank you for the insight regarding the switching in the output side, I will look into this more.
 
My assumption was that the three phase power fed into the HLV-H was transformed/inverted within the electrical panel to run the accessory single phase and dc motors. Is this correct?

Yes

Many people are quite adamant that a VFD is a bad idea on the HLV-H. Now I understand that running at a lower/higher frequency will mess with the accessory motors but could I used the VFD simply as a digital phase converter? I realize it does not take advantage of all the benefits of a VFD but in this case I just want a simple unobtrusive way to run the lathe.

It wouldn't be a bad idea except for the way the on/off and low/high speed controls work. The lathe panel button for on/off will initiate a clunk sound because a set of contacts is closing. Then when you work the low/high speed lever another set of contacts will make a clunk sound. You don't want this kind of activity on the output of your VFD even if it is operating at a fixed frequency.

I could come up with a way to sequence the low voltage switching first before the VFD is turned on. That would mean a separate supply for the low voltage controls and some changes in the electrical cabinet. It would also require that you stay in the low or high speed range. Using a RPC is easier.
 
I learned a long time ago that a VFD is not a phase converter in that they don't simply substitute for a rotary phase converter unless you are only running one motor and are only using the VFD logic controls to operate that motor.

I wired a Hardinge HSL speed lathe with a VFD and bigger 3 phase motor that is far superior to the OEM motor and control. Instead of three spindle speeds, forward only, I have reversing and a much wider range between lowest and highest speed with complete variability. I built a filing machine in 1976 with a single speed, single phase motor. Once VFD's got cheap (a little one used to cost $1000), I installed a VFD and 3 phase motor, making it a better machine.

But my 440 V TFB-H is run from a rotary phase converter and a 3 phase transformer that makes power close enough to 440 V 3 phase to trick the main drive motor and all the extra motors into normal operation while leaving all the OEM switches and levers to do what they were meant to do. The fake 3 phase power hooks up to the input terminals in the lathe control enclosure. Period. No messing with any of the lathe wiring, but you do have to watch which input wire goes to which input terminal, which you would have to do if even if you were feeding it real 3 phase power. As simple as it can get. Even simpler if you are lucky enough to get a 220 V lathe.

Larry
 
Years ago, I purchased and mounted a small, dedicated, rotary converter for an HLV-H inside the lathe cabinet. I built a small frame and used isolation dampers to keep it quiet. All I added was a toggle switch to the face (operator's side) of the electrical cabinet. I took the two single-phase lines right off the fuses inside and then fed back to the third leg fuse from the rotary converter. Very simple and tidy install.
 
1) set the varispeed drive at midpoint.

2) wire the VFD direct to the motor, fixed in hi range.

2a) disconnect all the associated original wiring, fuses, contactors, switches, etc.

3) you probably don't run coolant, correct?

Then you are done. Use the VFD logic controls to change speed and set fwd/rev.
 
Vfd's as already mentioned as already mentioned are designed to take over all controls that are downstream of it, using controls downstream and not controlled by the vfd is a quick way to ruin the vfd. You will find many examples of ways to do it, but unless you are willing to redo everything, then just supply 3 phase to the machine and let it work the way it was designed. You can buy a plug and play rpc that will run this machine for about 450. You mention space constraints, they take up about 3sq foot on your wall, I use the smaller model from American rotary I have 8 machines, only run 1 at a time, since it's just me, and it works great
 
Thank you everyone for the detailed explanations. I am currently researching an RPC (American Rotary 5hp and Phase-a-matic units)and have a general question on wiring to the RPC to the Hardinge. From what I have read (and was told by the salesman), there should be a 3-phase switch/breaker/magnetic safety switch/fused safety switch between the control box and the lathe. My understanding is that there will be two phases to the lathe at all times and the additional switch prevents someone from trying to start the lathe without having the RPC operating and thus causing damage. My question is, of all the options listed above, it seems that the magnetic safety switch is the only one that should ensure that the power is interrupted as the others can be left on thus negating the purpose of having them. Is this correct?

Cheers,
Jason
 
Thank you everyone for the detailed explanations. I am currently researching an RPC (American Rotary 5hp and Phase-a-matic units)and have a general question on wiring to the RPC to the Hardinge. From what I have read (and was told by the salesman), there should be a 3-phase switch/breaker/magnetic safety switch/fused safety switch between the control box and the lathe. My understanding is that there will be two phases to the lathe at all times and the additional switch prevents someone from trying to start the lathe without having the RPC operating and thus causing damage. My question is, of all the options listed above, it seems that the magnetic safety switch is the only one that should ensure that the power is interrupted as the others can be left on thus negating the purpose of having them. Is this correct?

Cheers,
Jason

What? Forget Phase-a-matic.

All you need is a magnetic contactor between the main power line and the RPC. A good RPC will already have that contactor inside. The power will only be on when the contactor is closed. The power to the idler on the RPC and the lathe occur at the same time.
 
I have a mid-70's HLV-H that I bought from a PM member. It is being powered by 208V single phase.

The lathe is set up with one VFD for the main drive motor and a very small VFD for the motor on the speed variator drive. I'm not running a coolant pump.

The setup works very nicely. Ironically I have real 3-phase power in my shop but see no reason to change the setup since it works so well.

So that is your option if you don't want to run a rotary phase converter or a Phase Perfect.
 








 
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