Quote:
Originally Posted by pugs
But what happens if you have a fet that is open and not short???? an open fet might not appear blown as in burn't either because it blows inside across the switching gate and has no outside or visual damage........if it can't turn but do's if you spin the rotor the chances are the one or two of the fets is open..... not shorted out  and this might not show on a meter reading because you are reading the working ones in the bank  |
If there is more than one FET for each pole of the motor then if one had gone open circuit, it would tesk OK, and the others would still work and drive the motor, just less efficiently,
If one was shorted, it would test as if all are shorted and probably cause it to get hot with or without a motor connected.