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Lathe Jaguar VXS inverter - remote pendant

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Sea.dog:
F03 - this is the maximum output frequency which, for an AC motor, is proportional to the RPM, so for 150 (Hz) you'd be getting three times the RPM. I use a top frequency of 100Hz.
F04 - is the minimum output frequency i.e. it controls the lowest RPM you wish to use. F03/04 of course are the maximum and minimum limits of the potentiometer.
F06/07 - are the ramp up and ramp down times. They control acceleration up to running speed (as determined by the output frequency) and deceleration (controlled by injecting a DC voltage to brake the motor. I use 2.5 secs. for my AUD
F10 - That depends on the motor. If you can't find a reference on the web then you'll need to open it up to determine the number.
F12 - Carrier frequency is the operating frequency of the internal digital circuitry. My TEAC was set to 4kHz and gave an annoying whistle. I set it above audible range. This can cause RFI (interference) problems depending on where the VFD is sited in relation to other equipment or radio/tv receivers.

Graham

Pete.:
Motor poles you can tell by the speed rating on the motor plate if it has one or just by measuring the rpm at 50hz. If your motor is doing 1400-ish RPM at 50hz it's a 4 pole. If it's doing 2800-ish it's a 2-pole.

raynerd:
Cheers Pete, will give that a bash today.

SeaDog I really appreciate your time in posting all that and I think I'm good with setting all except f3/4, I still don't feel I truly "get it"!


--- Quote ---F03 - this is the maximum output frequency which, for an AC motor, is proportional to the RPM, so for 150 (Hz) you'd be getting three times the RPM. I use a top frequency of 100Hz.
F04 - is the minimum output frequency i.e. it controls the lowest RPM you wish to use. F03/04 of course are the maximum and minimum limits of the potentiometer.[\quote]

So are you saying that that freq is 3x RPM. So if you are running 100hz you only have a top speed of 300RPM? I am missing something - I'm sure it is me being stupid just I am still none the wiser as to what to set theses values to!
--- End quote ---

hopefuldave:
Not too sure on F04 - on my own ABB and others I've set up the "base frequency" is the normal mains frequency the motor expects, i.e. 50Hz for rest of the world, 60Hz for America.
 The VFD uses this to work out the V/Hz curve when driving the motor, below base frequency the motor voltage is lowered as the inductance of the motor means its impedance drops with frequency, setting base frequency too low will apply too much voltage and send the motor over-current. Having the right V/Hz curve below base frequency puts the motor into constant-torque mode (one reason why you still need back-gear and gears to get best performance from a VFD-motor combination) and once above the base frequency the full mains voltage is applied, giving close to constant-power operation.

There should be a separate parameter to set the minimum frequency (F02?), which could be 0Hz if you wanted, be aware that motor cooling will be reduced a lot as the motor and its fan slow down (I *think* airflow is proportional to the square of the speed?) so either a thermal switch to halt the motor if it overheats or a cooling fan at low speeds is a Very Good Idea (I fitted a big axial fan on the end of the motor that "fails safe", comes on with the VFD's mains power and cuts out above 35Hz from the VFD** when the motor's own fan should supply enough cooling air, I run the motor down as low as 10Hz for jogging, a bit notchy but useful now and then, set my maximum to 85Hz to get 2500 RPM from a 1500 RPM lathe *for short periods* 150Hz may be a bit much unless the motor's built for it, a 3000 RPM motor would be running at 9000, might do a good impression of a hand-grenade).

HTH,
Dave H. (the other one)

**you may have the option to configure one of the VFD's relay outputs to open at a configured "supervisory frequency" if you want this feature and the VFD supports it

Pete.:
I actually typed the same thing this morning about base frequency but deleted it because I didn't know if it was the terminology they used for minimum.

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