SIRIUS motor protection circuit breaker with overload relay
The Siemens 3RV2131-4WA10 is a SIRIUS motor protection circuit breaker that integrates the overload relay function directly into the breaker body — no separate overload block needed. It's designed for protecting three-phase motors against short-circuit and overload conditions, with a Class 10 trip characteristic that clears overloads fast enough to protect standard induction motors during start-up. Rated operating voltage range spans 20 to 690 V, and the unit delivers 30 kA breaking capacity at 400 V — enough to handle high-fault-current industrial panels without cascading upstream breakers. Mounts via screw or snap-on onto 35 mm DIN rail per DIN EN 60715, in any orientation. Terminal capacity accepts up to 2x 35 mm² or 1x 50 mm² solid/stranded copper, using M6 screw-type terminals on the main circuit. Phase failure detection is built in — if one phase drops, the breaker trips, preventing single-phasing damage to the motor. No ground fault detection on this variant.
Breaking capacity across voltage levels
The interrupting capacity varies by line voltage: 100 kA at 240 V, 30 kA at 400 V, 4 kA at 500 V, and 2 kA at 690 V. For 480 V systems it's rated 52 A continuous, and at 600 V also 52 A continuous. Maximum switching frequency under AC-3 duty (motor starting) is 15 operations per hour — fine for conveyor or pump cycling, but not for rapid reversing applications.
Dimensions and clearances
Physical footprint: 75 mm wide, 140 mm tall, 149 mm deep. Required clearances for heat dissipation: 50 mm above and below, 10 mm to the side, zero forward or backward clearance needed.