The Siemens 5SN6225-8CP is a 2-pole miniature circuit breaker from the SENTRON 5SN series, rated for 400 V AC at 50 Hz. It provides overcurrent and short-circuit protection for branch circuits in distribution boards, control panels, and machinery.
Physical Fit and Installation
The top and bottom terminals accept solid conductors up to 35 mm², which covers the range from 1.5 mm² lighting circuits up to 10 mm² feeder taps in a sub-distribution board. The 90 mm height leaves clearance under a standard 120 mm distribution board cover.
Electrical Ratings and Application
Rated for multi-phase and single-phase operation at 440 V AC maximum, with a DC voltage rating of 72 V maximum — so it can also serve as a DC branch protector in control circuits supplied from a 48 V or 60 V battery bank, provided the fault current stays within its DC interrupting capability (not separately stated, but the DC rating is the voltage limit). Power loss per pole at rated current in hot operating state is 2.1 W; for a 2-pole breaker that is 4.2 W total heat to dissipate inside the enclosure, which matters when grouping multiple breakers in a sealed panel.
Environmental Range
No derating curve is provided in the spec record, but the -40 °C floor is unusual for a standard MCB — it signals suitability for outdoor telecom shelters or unheated electrical rooms in northern climates.