What it is and what it does
The Siemens 3RV2131-4VA10 is a SIRIUS motor protection circuit breaker designed for motor protection with an integrated overload relay function. It combines short-circuit and overload protection in one device, sized for motor loads up to 45 A at 480 V and 45 A at 600 V. Rated for a supply voltage range of 20 to 690 V, it delivers a breaking capacity of 30 kA at 400 V and 100 kA at 240 V — enough to handle high-fault-current panels without cascading upstream. At 690 V the breaking capacity drops to 2 kA, so verify the available fault current at that voltage level. The Class 10 trip characteristic means it clears overloads fast enough to protect standard induction motors during start-up — a common requirement for pump, fan, and compressor duty. Phase failure detection is built in; ground fault detection is not.
Mounting and integration
Mounts via screw and snap-on onto a 35 mm standard mounting rail per DIN EN 60715, in any position. The 75 mm width and 140 mm height fit a standard MCCB slot in a motor control center; depth is 149 mm. Clearance requirements: 50 mm upwards and downwards, 10 mm at the side, zero forwards and backwards. Main circuit terminals are screw-type, accepting 2x 1 to 25 mm² or 1x 1 to 35 mm² solid or stranded conductors. Screw size is M6. The operating temperature range is -20 to +60 °C, with temperature compensation active across that span.