Had a True T23F tripping a breaker. Isolated down to the condenser. Ohmed comp windings as good. No issues there. Megger tests to compressor case was good too.
With condenser practically in my lap, using an extension cord and an in-line GFCI as aux power source, I'd plug in condenser. The compressor would do an abbreviated startup kick along with the sound of something from the compressor's vicinity akin to the nearly imperceptible noise of dropping a tennis ball on carpet from say...a foot high.
I ordered and replaced the start components. SAME RESULT!
Retested compressor. Same readings. Compressor WASN'T testing as shorted.
Disconnected compressor terminals. Applied power. Carefully touched line input to C terminal. Tennisball noise and GFCI tripped.
Now I have no faith in my megger.