Part identity and class
The ABB 1SAZ511301R1002 is a thermal overload heater for starters, listed under the Contactors and Starters category as part of the broader Circuit Breakers, Fuses & Protection line. Heaters in this class mount to the matching ABB overload relay base and carry the motor heating element that trips the relay on sustained overcurrent — they are the consumable, current-rated element inside the starter assembly, not a standalone protective device.
Panel-side fit and integration
On the panel, the heater clicks into the matching ABB overload relay base — wiring practice is the same spring/screw cage pattern used across the line, so the panel builder's termination rhythm carries over from adjacent starters. The check that matters at FAT is that the heater's current range brackets the motor's full-load amps with the relay dial set inside that range; a heater that is one size bracket off will nuisance-trip on cold start or fail to protect on locked rotor.