What this MCB brings to a 63 A distribution board
The Schneider A9F03763 is an Acti9 iC60N miniature circuit breaker rated 63 A with a B-curve trip characteristic, 3P+N poles, and a 36 kA breaking capacity at 133 V AC. At 400 V AC the breaking capacity drops to 6 kA (Icn per EN/IEC 60898-1) and 10 kA Icu per EN/IEC 60947-2, so for a 400 V board verify the prospective fault current at the point of installation — this breaker is rated for Category A utilisation, meaning it is not intended for current-limiting applications that require Category B selectivity.
The 72 mm width (8 x 9 mm pitches) and 91 mm height fit a standard modular enclosure row; depth of 78.5 mm leaves clearance for a 100 mm deep enclosure with wiring space behind. IP20 finger protection on the front; the toggle and trip indicator are visible through a sealed gland plate.
Dual-certified to EN/IEC 60898-1 and EN/IEC 60947-2, which covers both domestic distribution and industrial branch-circuit applications. Suitability for isolation is confirmed under both standards — the contact position indicator gives a visible gap when the toggle is off, so a qualified electrician can work downstream without a separate isolator.