The Siemens SENTRON 5SP3735-3 is a 1-pole miniature circuit breaker rated 35 A with an E tripping characteristic, designed for 230 V AC, 50 Hz systems.
The E characteristic (class E) is a less common curve than B/C/D — it sits between C and K in magnetic trip threshold, typically used for transformer or motor-start protection where a moderate inrush delay is needed without the wide band of a K curve. At 35 A and 25 kA SCCR, this breaker handles general lighting and distribution loads in commercial or multi-residential subpanels where fault levels are high but load inrush is moderate. The 6 kV surge voltage resistance confirms it can withstand transient overvoltages typical at the service entrance without nuisance tripping or damage. Conductor cross-section from 2.5 mm² to 50 mm² (solid or stranded) via saddle terminals gives flexibility for both downstream branch wiring and incoming feeder cables. The 1.5 width units (approx. 27 mm on a 35 mm DIN rail) is wider than a standard 1-pole MCB — account for this when laying out the panel to avoid running out of rail space.
The integrated locking slide accepts a padlock, wire seal, or cable tie — useful for lockout/tagout on a main breaker position. Supply cord can enter from any position (top or bottom feed), and infeed at the box terminal is supported — no forced orientation.