The Schneider Electric A9N16246 is a 2-pole residual current circuit breaker (RCCB) from the Acti9 xID family, rated at 63 A with a 300 mA earth-leakage sensitivity. It's a Type A-SI (Super Immunised) device with a selective time delay, meaning it's built for circuits where nuisance tripping from high-frequency harmonics or surge currents is a concern — common on supply lines feeding VFDs, UPS systems, or welding equipment. The selective delay coordinates with downstream RCCBs so only the faulted branch trips, keeping the rest of the installation live.
The 63 A continuous rating (In) covers the full load of a typical sub-distribution board feeding multiple final circuits — sized for a 3-phase incomer on a residential or light commercial DB. The 300 mA sensitivity is the standard for fire protection (not personal shock protection), so this RCCB goes upstream of the 30 mA devices on socket outlets. The Type A-SI classification handles pulsating DC fault currents and is immunised against unwanted tripping from 50 Hz harmonics and transient surges up to several kA — the SI suffix means it passes the 3 kA surge-withstand test per IEC 61008-1 without tripping. The selective time delay (marked "S") introduces a deliberate 40-150 ms delay before tripping, allowing downstream 30 mA RCCBs to clear first; if they don't, this unit backs them up.
Tunnel terminals accept 1-35 mm² rigid or 1-25 mm² flexible copper — strip 14 mm, torque to 3.5 N·m. The 18 mm phase-to-phase pitch matches the Acti9 busbar system for a clean feed through a distribution board. IP20 rated for enclosure use only; no washdown rating.
Standards and environmental
Designed and certified to IEC 61008-1, EN 61008-1, and EN 61008-2-1 — the core RCCB standards for residual current protection. Storage range -40 to 85 °C covers most site conditions. Pollution degree 2 (normal, non-condensing). Isolation suitability is confirmed, with a visible contact position indicator and padlocking provision for lockout/tagout.