The smaller drives only had flag fuses which did double duty as main fuse AND alarm, the larger capacity had a large 3 phase fuse bank as well at the top of the drive, each fuse being in parallel with one each flag fuse.
MS connector is a multipin for the encoder and thermal switch, you cannot see the switch without opening up the motor, but testing across the pins for it, you can check continuity.
It should show shorted, open for fault.
Al.