SIRIUS 3RV1031-4FA10-ZX95 — motor protection circuit breaker, 40 A, CLASS 10
The Siemens 3RV1031-4FA10-ZX95 is a SIRIUS motor protection circuit breaker rated 40 A continuous current, designed for motor protection with CLASS 10 trip characteristics. It switches 18.5 kW at 400 V and carries a 50 kA breaking capacity at 400 V AC, dropping to 10 kA at 500 V and 4 kA at 690 V — the high fault current at 240 V hits 100 kA. The 40 A rating and CLASS 10 trip mean it protects standard induction motors against overload and short circuit, tripping fast enough for most pump, fan, and conveyor applications without nuisance tripping on startup inrush. Phase failure detection is built in; ground fault detection is not.
Mounting and integration
Snap-on mounting onto 35 mm DIN rail per DIN EN 50022, plus screw fixing. The 55 mm width and 140 mm height fit a standard MCCB slot; depth is 149 mm. Mounting position is any — no derating for horizontal or vertical orientation. IP20 on the front means it is protected against finger contact but not washdown; install inside a panel. The screw-type terminals for the main circuit accept 2x solid conductors 0.75–16 mm² or 2x stranded 0.75–25 mm², with a single larger terminal taking up to 35 mm² stranded. Auxiliary and control circuits also terminate on screw terminals. Zero clearance needed at the sides or rear — 0 mm backwards and at the side.
Electrical and environmental ratings
Rated insulation voltage 690 V, surge voltage resistance 6 kV. Operating temperature range -20 to +60 °C; storage and transport -50 to +80 °C. Shock resistance 25g at 11 ms. Power dissipation at rated current in hot state is 29 W total, 9.7 W per pole — factor that into enclosure thermal calculations. Operating frequency at AC-3 duty is 15 cycles per hour maximum. RoHS compliance date is July 1, 2006.