Author Topic: VFD motor controller help needed  (Read 1522 times)

Offline picclock

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VFD motor controller help needed
« on: August 16, 2016, 08:13:50 AM »
Hi
I'm new to the VFD 3 phase thing. I'm using it to control a 1.5hp, 3 phase motor. The VFD model in question is a HY02D223B, a std 220V in, to three phase out 2.2kW controller. I can get the motor to start and run OK but it lacks torque. I can stop it easily with my hand holding a 100mm pulley. The motor is connected with three wires, each going to one end of the three windings. The other end of the winding are connected together and go nowhere else. I have measured the voltage across the output connections, phase to phase, and it is only 140V or so. Phase to motor winding common is around 90V.  The voltage is equal across all windings so its not a phase issue. 

My limited understanding of the way these things operate is that the mains is full wave rectified to produce +/- 310 volts which is then switched hi/lo or off using insulated gate bipolar transister. The power to the motor is then controlled by using the on/off ratio of the switches, which also helps to make a sine wave.

The vfd also has a torque compensation setting (Pn 13 - value 0-4) which I have set to 3.5. A note next to the setting indicates large parameters may damage the motor. This appears to be the only way to get some torque though nowhere near as much as it should be.

So far I am using the vfd front panel to do the controlling, so no issues there.

If anyone has one of these could you measure the phase to phase voltage to confirm if this is the problem or just a red herring ? Just measuring using a std multimeter on AC Volts.

Any help or info much appreciated.

Best Regards

picclock
Engaged in the art of turning large pieces of useful material into ever smaller pieces of (s)crap. (Ferndown, Dorset)

Offline philf

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Re: VFD motor controller help needed
« Reply #1 on: August 16, 2016, 08:24:49 AM »
Hi Piclock,

It sounds as though your motor is connected star and not delta which it should be for a 220v output inverter.

If connected delta there are no "other ends" of the windings.

See: http://www.inverter.co/single-phase-inverters-224369.html

Phil.
Phil Fern
Location: Marple, Cheshire

Offline picclock

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Re: VFD motor controller help needed
« Reply #2 on: August 16, 2016, 09:02:01 AM »
Hi PhilF

Thanks for the info and the link. It sounds like a plan.

No info in the 'manual' as to which configuration so I will go and give it a try.

Best Regards

picclock

Tried it and its all sorted  :nrocks: . Loads of torque, and unstoppable by me without burning my pinkies. Many Thanks  :beer:
Engaged in the art of turning large pieces of useful material into ever smaller pieces of (s)crap. (Ferndown, Dorset)

Offline David Jupp

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Re: VFD motor controller help needed
« Reply #3 on: August 16, 2016, 11:15:59 AM »
Now remember to go back and return the torque compensation value to 'normal', unless of course your application really needs it.

Offline philf

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Re: VFD motor controller help needed
« Reply #4 on: August 16, 2016, 02:10:30 PM »
Good news!

Glad it's sorted.

Phil.
Phil Fern
Location: Marple, Cheshire

Offline JHovel

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Re: VFD motor controller help needed
« Reply #5 on: August 17, 2016, 07:44:29 AM »
...andthe likely reason you measured 90V across the phases is that your multimeter is designed to averageout sinus wave forms and the VFD produces only a rough approximation with steep steps up and down and the multimeter can't follow that fast and shows you the average of it 'sees'. An oscilloscope would show you the actual tops and shoae and you could then calculate the real RMS - if you are so inclined.
Cheers,
Joe
Cheers,
Joe