SCHNEIDER A9R74263 Residual Current Circuit Breaker (RCCB) Type AC 2P 63A 300mA

SCHNEIDER A9R74263 RCD circuit breaker, RCCB residual current protection device, Type AC 2P 63A 300mA
SCHNEIDER A9R74263 is a DIN rail mounted residual current circuit breaker, suitable for 1-phase electrical systems with high loads up to 63 A. The highlight of this model is its 300 mA tripping sensitivity, which is the rating used to prevent property damage or fire caused by earth leakage currents from insulation faults. Since 300 mA sensitivity is not sufficient for complete direct personal contact protection (which requires 30 mA), the A9R74263 is often installed as upstream/main protection to achieve discrimination/selectivity with high-sensitivity 30 mA earth leakage breakers installed downstream.

Specifications
- Fire Hazard Protection: With a 300 mA sensitivity, this device focuses on preventing the risk of fire caused by accumulated leakage currents in the system.
- High Rated Current: Supports high load currents up to 63 A, suitable for use as a main breaker in high-power control panels.
- Voltage Independent: The tripping mechanism operates independently of the supply voltage, ensuring protection remains reliable even under abnormal voltage conditions.
- VisiSafe & VisiTrip: Features that enhance safety and speed up circuit troubleshooting.
- Durable Design: High mechanical and electrical durability (20,000/15,000 cycles) according to Acti9 standards.

Applications & Usage
- Main protection in main distribution boards: Used as the main RCCB to protect against earth leakage in large buildings before branching out into various sub-circuits.
- Fire protection: Installed in areas with high amounts of flammable materials or in systems requiring monitoring of leakage currents that could generate excessive heat.
- Selective System: Used in conjunction with 30 mA low-sensitivity RCCBs or RCBOs in branch circuits, so that when an earth leakage occurs in a branch circuit, only the downstream breaker trips, allowing the rest of the system to continue operating normally (Time/Current Selectivity)