DIYbanter - View Single Post

Jon Elson[_3_]

wrote:

l have come across quite a number of refrigerators that has inverter for
its compressor motor these days. The problem is these compressors will not
work when connected to 50 or 60HZ mains. Please can someone give me an
explanation on how these circuits work, how to test both circuit and
compressor? Thanks
The problem is the motors have no provision for starting, that is supplied
by the motor drive circuit that gradually increases applied voltage and
frequency as the motor picks up speed.

If the windings are not shorted to the housing, the motor is most likely
good. (Can't test the compressor as a whole so simply.)
The drive circuits are VERY complex, probably using IGBTs and a logic
circuit to drive them, which likely has a microprocessor in it.
I'm not sure we can really tell you how to test the drive circuit on such a
forum as this. And, be aware there are dangerous voltages in such circuits.

Jon