Inverter and 3Ph Motor - Very slow revs

[CaptainBarnacles]

Hi All,

I bought myself a new motor (0.55kw, dual voltage, 4 pole) for my Myford lathe and to test it I thought I'd hook it up to my Chinese 2.2kw VFD that I bought for my CNC router. I have used the VFD with router spindle and it works fine so I know that the VFD is functional. I swapped the links in the motor to make it delta configuration and wired up U,V,W and Earth to the VFD and powered up.

On the VFD I pressed the Run button and slowly started to increase the frequency. The motor started to turn slowly but as I increased the Hz the shaft slowed and eventually stopped turning altogether. The thing I found most wierd was that the motor sounded like it was getting faster as I increased the Hz on the VFD but the shaft speed didn't reflect that. I would say that it reaches about 50-60 RPM (not Hz) before the shaft speed drops off again.

The VFD is completely unaltered from new, I haven't changed any of the parameters. I have looked through the manual and I can't see that any of the parameters would have an effect on the symptoms that I am experiencing - but I'm certainly not sure of that. I have tried swapping a couple of the phase wires around, rechecked all my connections, turned it off and back on again (a 25 year career in IT - can you tell?), checked the ribbon cable to the VFD's control panel, and re-wired it all up again in case I had a brain-fart but I am still getting the same result. Anyone know where I might be going wrong - am I doing something properly daft? Or could I have a duff motor?

[JAZZCNC]

Completely different motor to the Chinese spindles so you will need to re-program the VFD parameters to suit.
Give me the details of the motor ie: current, volts etc and I'll take a look and tell you which parameters to change.

Edit: And the Vfd make and model just in case it's not a huanyang

[CaptainBarnacles]

Here's a picture of the spec plate. Oh, and the VFD is a HY02D223B. Cheers Jazz.

27534

[JAZZCNC]

Erm, I've left my manual for Huanyang VFD at work but I've done enough of these now to know these are the main parameters to check and looked back at a few posts to verify.
Obviously make a note of the current settings before changing so can set back.

Pd04 = base frequency so need 50hz
Pd05 = Max freq so set this to the max you want to run this motor at ie: 100hz wouldn't go above that.
Pd08 = Max voltage set to 240V
Pd141 = rated volts set to 230V
Pd142 = rated current set to 2.74
Pd143 = # poles set to 4
Pd144 = motor speed set 1370

[CaptainBarnacles]

You're a legend Jazz. I'll give it a go.

[CaptainBarnacles]

Result!

As ever I'm in your debt. :beer:

I'm kicking myself for not having spotted the rated current setting. I was mighty surprised that the frequency was set to 400Hz, I just assumed that it would be 50Hz. Clearly the spindle operates at much higher frequencies than the squirrel cage motor and presumably that's how it reaches 24k RPM. I have some motor related bedtime reading tonight!

[JAZZCNC]

I'm kicking myself for not having spotted the rated current setting. I was mighty surprised that the frequency was set to 400Hz, I just assumed that it would be 50Hz. Clearly the spindle operates at much higher frequencies than the squirrel cage motor and presumably that's how it reaches 24k RPM.

I'm no expert on VFD's but sure your problem was more the Frequency than the current but yes wouldn't help. This is why I said wouldn't run much more than 100hz with a 50hz motor and why you heard the frequency change but not the speed as the motor got saturated. Suppose it's a little like when steppers get saturated at high rpm and stall.

[Voicecoil]

Another issue could be that a 50Hz motor is likely to have a rather higher inductance than a spindle?? hence if you apply 400Hz, you'll only get 1/8th of the current, which won't get it going well.