Motor protection circuit breaker, SIRIUS 3RV2011-1GA25-ZX95
The Siemens SIRIUS 3RV2011-1GA25-ZX95 is a motor protection circuit breaker designed for the main current circuit of three-phase motors. It integrates overload and short-circuit protection in a single device, with a Trip Class 10 characteristic — meaning it will trip within 10 seconds at a locked-rotor current of 7.2× the thermal setting, per IEC 60947-4-1. This makes it suitable for standard induction motor starting profiles where the inrush transient decays within that window. The breaker carries a 100 kA breaking capacity at 400 V AC, which covers most industrial distribution fault levels without requiring an upstream current-limiting fuse. At 690 V the breaking capacity drops to 4 kA — still adequate for a motor branch circuit fed from a 690 V supply with a transformer-limited fault current. Phase failure detection is built in, so the breaker will trip if one phase is lost — a common cause of single-phasing motor damage. Ground fault detection is not included, so a separate ground-fault module or residual-current device would be needed for that layer of protection.
Mounting and wiring
Mounts via screw or snap-on onto a 35 mm standard mounting rail per DIN EN 60715. The 45 mm width means it occupies a single 45 mm module on the rail — standard for this class of motor-protective device. Any mounting position is permitted, so vertical or horizontal rail orientation is fine. The main current circuit uses spring-loaded terminals, accepting 2 × (0.5... 2.5 mm²) solid or stranded conductors. No screw torque to verify — just strip to 8–10 mm and push in. The 97 mm depth leaves clearance for wiring ducts or adjacent components on the rail. Clearance requirements: 50 mm upwards and downwards, 30 mm at the sides, 0 mm forwards and backwards. That 0 mm forwards/backwards means the breaker can be butted directly against the back panel or enclosure door without derating — useful in shallow enclosures.
Auxiliary contact ratings and switching capacity
The auxiliary contact block (integrated or add-on, depending on variant) is rated for switching at several control voltages: 1 A at 24 V, 0.5 A at 120 V, 0.5 A at 125 V, 0.5 A at 230 V, and 0.15 A at 60 V. These are the maximum continuous currents for the respective AC/DC voltage levels — useful for PLC input or contactor coil circuits. The main power circuit is rated for gL/gG fuse backup at 50 A at 400 V, 40 A at 500 V, and 35 A at 690 V. These values define the maximum fuse rating that can be placed upstream while maintaining the breaker's short-circuit coordination.