The AC-4 rating of 12.5 A at 400 V governs reversing or inching duty — the contactor's ability to break motor starting current repeatedly. At 690 V, the contactor is rated for 7.5 kW, and at 500 V also 7.5 kW, covering common European and North American motor voltages. The AC-12 rating of 10 A applies for resistive loads in control circuits. Type 1 coordination requires a 63 A gL/gG fuse upstream; This matters when designing for selectivity in a motor control center — the fuse size directly affects the upstream breaker coordination.
Screw terminals accept solid conductors from 2x 0.5 mm² up to 2x 4 mm², and stranded conductors up to 2x 10 mm².