What this RCCB is for
Installation fit and panel integration
Snaps onto DIN rail (REG) in any mounting position. Occupies 4 modular width units (4 MW) at 72 mm wide, 90 mm tall, 77 mm deep — the 77 mm depth includes the housing; installation depth is 70 mm. IP20 with connected conductors inside an installed distribution board.
Type B+ — what it catches that Type A misses
Type B+ RCCBs respond to smooth DC residual currents up to the rated value, not just AC or pulsed DC. That matters on circuits with variable-speed drives, photovoltaic inverters, or EV supply equipment where a semiconductor fault can produce a pure DC leakage path. The short-time delayed design prevents nuisance tripping from transient surge currents; it is rated to withstand a 3 kA surge current and a let-through current of 7 500 kA.
Thermal derating and service life
Rated 25 A continuously at ambient up to 45 °C. Above that, derate: 23.5 A at 50 °C, 22 A at 55 °C, 20.5 A at 60 °C, 19 A at 65 °C, 17.5 A at 70 °C.