It combines overcurrent and residual current protection in one assembly — a common approach in final-distribution boards where space is tight and selectivity matters. Type A means it detects sinusoidal AC fault currents plus pulsating DC fault currents, covering most modern electronic loads like switched-mode power supplies and variable-speed drives.
The 63 A rating governs the maximum continuous load.
The unit occupies 3 width units — 54 mm of rail space — and requires 70 mm installation depth. Terminal capacity accepts solid conductors 0.75 to 35 mm² and stranded 0.75 to 25 mm².