The Siemens SENTRON 5SM1746-6 is a 4-pole residual current circuit breaker (RCCB) rated 63 A at 40 °C with a 500 mA tripping fault current, Type A sensitivity. It mounts on a DIN rail (REG) and is designed for 50 Hz networks at 400 V AC supply voltage. The 10 kA short-circuit current rating (SCCR) per IEC 61008-1 means it can safely interrupt fault currents up to that level without upstream damage — a key coordination figure for panel builders.
Ratings & Fit
Rated 63 A continuous at 40 °C ambient; derates to 60.48 A at 50 °C, 57.96 A at 55 °C, 55.44 A at 60 °C, 52.92 A at 65 °C, and 50.4 A at 70 °C — so in a warm panel the effective current capacity drops. The 500 mA trip threshold suits circuits with higher leakage (e.g., long cable runs or industrial loads) where a 30 mA device would nuisance-trip. Type A detects pulsating DC residual currents from rectifiers or VFDs, not just sinusoidal AC. The 4-pole design (3 phases + neutral) is standard for three-phase distribution boards. Overvoltage category III means it's rated for fixed-installation downstream of the main distribution board. IP20 with connected conductors — suitable for enclosed distribution boards only, not outdoor or washdown locations.
Mounting & Panel Integration
Snap-on DIN rail (REG) mounting, any position. Occupies 4 modular width units (approx. 72 mm at 18 mm per unit). Installation depth 55 mm. Supply connection top or bottom. Silicon-free construction. Mechanical service life typical 10 000 switching cycles.