The Siemens 5SP3435-3 is a SENTRON main miniature circuit breaker, 4-pole, rated 35 A at 400 V AC with an E tripping characteristic. That E-curve means it's designed for transformer and motor-starting loads where inrush is higher than a standard B or C curve handles — it holds through the magnetizing surge without nuisance tripping, then clears fast on a hard fault. Breaking capacity is 25 kA per EN 60898, so it's rated for commercial and light industrial service entrance panels where fault current runs that high.
Mounting and integration
Snaps onto standard DIN rail (35 mm). Occupies 6 modular width units — plan for that in the panel layout. IP40 with conductors connected, so it's fine inside a closed enclosure but not for washdown zones. Degree of pollution 3, overvoltage category IV — this is a main breaker, not a branch device; it sits at the panel infeed where surge exposure is highest.
Thermal derating and wiring
Rated 35 A at 30 °C ambient. Derates to 33.25 A at 40 °C, 31.5 A at 50 °C, and 30.625 A at 55 °C — if the panel runs hot, size the upstream protection accordingly. Terminals accept 2.5 to 50 mm² solid or stranded, with saddle terminals and box-terminal infeed. That 50 mm² top end handles the main feeder cable without pigtails.
Lifecycle and sourcing
Current production — no end-of-life notice on this order code. Sourced and quoted to order against an RFQ through independent distribution; availability and current pricing confirmed at quote time. The integrated locking slide accepts a padlock, wire seal, or cable tie for lockout/tagout compliance.