The Siemens 5SM3314-0KL is a SENTRON residual current operated circuit breaker (RCCB), 2-pole, type AC, rated at 40 A with a 30 mA trip sensitivity at 230 V AC. It is designed for instantaneous fault-current detection and carries a 10 kA short-circuit current rating. The N-left configuration means the neutral conductor connects on the left side of the device, which matters when laying out the DIN-rail assembly in the distribution board.
The 40 A rated current and 30 mA residual trip are the two numbers that decide whether this RCCB fits your circuit. The 40 A is the continuous load it can carry without tripping on thermal overload — sized for a 40 A feeder or submain. If your service entrance has a higher available fault current, you would need to coordinate with a current-limiting upstream MCB or fuse. Ambient temperature range is -5 °C to +45 °C for normal operation, with storage extremes of -40 °C to +75 °C. The -5 °C lower limit means it is not rated for unheated outdoor enclosures in freezing climates — the bimetal or electronic trip elements may not respond within spec below that point. The 45 °C upper limit is typical for enclosed distribution boards; if the panel internal temperature exceeds that, derating applies.
Installation depth is 70 mm, which fits standard distribution board enclosures. IP20 protection applies once the conductors are connected and the board is closed — the device itself is not rated for wet or dusty environments. This is not a device intended for frequent manual switching — it is a protective device. Each trip event counts as one cycle, and the mechanism is rated for that many operations before replacement is recommended. The test button requires a minimum of 100 V to function, so it will not trip the test circuit on a low-voltage supply.