The Siemens 5SN6210-8CP is a 2-pole miniature circuit breaker from the SENTRON 5SN series, rated for 400 V AC at 50 Hz. The 10 000 mechanical operating cycles are typical for an MCB in a panel that sees occasional switching — not a contactor duty cycle, but adequate for a protective device that trips infrequently.
The dual breaking capacity is the main spec to check against your supply transformer and cable length. At 6 kA per EN 60898, this breaker clears faults in standard residential/commercial panels. Rated 400 V AC for multi-phase operation, with a maximum of 440 V AC. DC rating maxes at 72 V.
Accepts solid conductors up to 35 mm².