VFD Drive

There are other pertinant data to consider. Please expound.

The correct response is, ask Schneider, they are the only ones who can accurately respond based on the design of their product.

As a general rule, VFDs can be connected to motors as low as 50% of their intended rating. Technically it would not matter at all, but in programming you must tell the VFD what the motor FLA is, and many mfrs have the programming lower limits set to 50% of the rating. This is (generally) because of measurement error that will increase at lower levels of current through the sensors. For example most use Hall Effect transducers to sense current. At the rated current of 65A they are typically looking at 0 to +5VDC from the transducer and the FLC should fall into the +3VDC area to allow working room above and below. But if connected to a motor that is only 10A FLC, that same transducer range makes the measurement now crowded into 0 to 0.77VDC, too narrow to be reasonably accurate.

Simple rule of choosing the inverter, choose one which capacity is not less than the motor capacity. See #4 comment @ http://cr4.globalspec.com/thread/68086#newcomments

For this case, Thing may happen is that the torque produced by the inverter may exceed the torque of motor then the motor may become overtemperature. If the inverter has a torque regulation, then you will adjust so there would not be an issue.

It isn't the inverter that determines whether or not the system is safe. It is the overload trip setting in the inverter parameter list and the supply fuses upstream of it; if it cannot be set low enough, then the overload trip will not prevent the motor from overload and burn-out.

The overload trip is there to protect the motor. The fuses are there to protect the cable. For guidance on this sort of thing, refer to British Standard 7671.

Welome to CR4, BTW.

Dear Mr.warlock,

The answer for your Question is YES - 30 KW RATING Motor WILL WORK IN A 45 KW VFD SYSTEM. It will safely work.

DHAYANANDHAN.S