The Siemens 5SV5642-6 is a SENTRON 4-pole residual current operated circuit breaker (RCCB), Type A, rated 25 A with a 300 mA trip threshold for 400 V AC residential and commercial distribution boards. It mounts on a DIN rail (REG), occupies 4 modular width units, and carries a 6 kA short-circuit current rating per EN 60898 and IEC 61008-1. The instantaneous design (non-delayed) means it trips on the first detectable fault — no intentional time lag for selectivity coordination downstream.
Fit and panel integration
The 70 mm depth and 72 mm width match the standard SENTRON modular footprint; the 90 mm height clears most enclosure lids without a deep gland plate. Mounting position is unrestricted (any orientation). The IP20 rating applies only when the distribution board is installed with conductors connected — treat it as a panel-internal device, not for wet or outdoor locations. Silicon-free construction is relevant for potting or conformal-coating processes in sensitive environments.
What the ratings mean for your BOM line
The 300 mA residual trip is a Type A characteristic — it detects sinusoidal AC faults plus pulsating DC faults up to 6 mA smooth DC superimposed. That covers most modern electronic loads (VFDs, switched-mode supplies, LED drivers) that can produce pulsating DC leakage. The 25 A rating is the continuous current at 40 °C ambient; derate above 45 °C. The 6 kA SCCR is the breaking capacity under short-circuit — adequate for residential and light commercial service entrances where the prospective fault current stays under that level. The 1 kA surge current resistance means it withstands lightning-induced or switching transients without nuisance tripping.