What it is and what it does
The Siemens SIRIUS 3RV1011-1GA15-ZI45 is a motor protection circuit breaker in the S00 frame size, designed to protect three-phase motors up to its rated operating current of 6.3 A. Its thermal overload release is adjustable from 4.5 to 6.3 A, so you dial it in to match the motor's full-load amps — no need to carry a separate overload relay for this range. The magnetic short-circuit release is fixed at 82 A, which clears a bolted fault fast enough to protect the contactor and cable. The CLASS 10 trip curve means it will disconnect on a locked-rotor condition within 10 seconds at 7.2× current, matching standard IEC motor starting requirements for most pumps, fans, and compressors.
Panel fit and integration
This breaker snaps onto a 35 mm DIN rail per DIN EN 60715 and can be mounted in any position — handy when you're squeezing it into a tight enclosure corner. The screw-type terminals on top and bottom accept up to 2.5 mm² stranded wire, and the S00 frame width of 45 mm means it occupies the same footprint as the matching SIRIUS contactor it pairs with, keeping the wiring straight and the panel layout clean. The built-in transverse auxiliary switch (1 NO + 1 NC) gives you a remote status signal without bolting on an extra block, saving one DIN slot.