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. The instantaneous design (non-delayed) means it trips on the first detectable fault — no intentional time lag for selectivity coordination downstream.
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. 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.
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 1 kA surge current resistance means it withstands lightning-induced or switching transients without nuisance tripping.