The Siemens SENTRON 5SM3621-4KK14 is a 2-pole residual current operated circuit breaker (RCCB), type B+, rated 16 A with a 300 mA trip sensitivity at 230 V AC. It is designed for DIN-rail mounting in distribution boards and carries a short-circuit current rating of 10 kA per IEC 61008-1 and EN 60898. The short-time delayed switching function (selective type) allows coordination with downstream devices, so that only the faulted branch clears on a ground fault — useful for maintaining supply to critical loads in a panel.
Selectivity and fault coordination
The short-time delayed design (type B+, selective) means this RCCB withstands a brief inrush or transient without tripping, giving downstream MCBs or RCCBs time to clear a fault first. The 10 kA SCCR at 230 V AC (per IEC 61008-1 and EN 60898) defines the maximum prospective fault current it can safely interrupt — sized for typical residential and light commercial distribution boards where fault levels stay under that threshold.
Mounting and panel integration
Occupies 4 modular width units (72 mm) on a DIN rail (REG). Depth is 70 mm, height 90 mm. Mounting position is unrestricted. The supply connection can enter from top or bottom; the SIGRES function (switched-off state detection) remains powered from the bottom supply even when the device is off. Rated IP20 with connected conductors in an installed distribution board — suitable for enclosed panels only, not for washdown or outdoor exposure.
Lifecycle and sourcing
Listed as current production. The part is sourced and quoted to order against an RFQ through independent distribution channels; availability and current pricing are confirmed at quote time. No official successor has been issued for this order code.
Environmental and installation notes
Rated for ambient temperatures from -25 °C to +45 °C; storage range extends to -40 °C. Silicon-free construction. Overvoltage category III. Mechanical service life is 10 000 operating cycles typical. Supplementary devices (auxiliary contacts, shunt trips, etc.) can be installed on the right side.