The Siemens 3VA2340-5HN32-0LC0 is a 3-pole IEC frame 400 molded case circuit breaker from the SENTRON 3VA2 series, rated for line protection with an ETU350 LSI trip unit. Its interrupting capacity hits 55 kA Icu at 415 V AC — that is the 'M' (medium) breaking capacity class, sized for industrial distribution panels where fault currents are substantial but not extreme. The continuous current rating In is 400 A, with overload protection Ir adjustable from 160 A to 400 A, and short-circuit protection Isd adjustable from 1.5 to 10 times Ir. Instantaneous pickup Ii is fixed at 10 x In. This breaker also includes a universal release 24 V DC accessory for shunt or undervoltage tripping, plus space for up to two auxiliary switches.
What the ratings mean for fit
The 55 kA Icu @ 415 V tells you this breaker can safely interrupt a fault current up to that level without welding its contacts or rupturing the arc chamber. In a 400 V distribution panel fed by a transformer of 1000 kVA or larger, prospective fault currents often exceed 25 kA — this unit handles that margin. The LSI trip (Long-time, Short-time, Instantaneous) gives you selective coordination: you can set the short-time delay so that a downstream breaker clears a bolted fault before this one trips, keeping the rest of the bus live. The ETU350 is an electronic trip unit, meaning it holds its calibration over temperature and allows finer adjustment than a thermal-magnetic. The 24 V DC universal release accessory is wired separately for remote tripping via a safety circuit or emergency-stop chain.
Deployment context
This breaker mounts into a standard Siemens 3VA2 fixed or plug-in base on a DIN rail or mounting plate inside a switchboard or distribution panel. The nut keeper kit (included) secures the breaker to the busbar assembly — a detail that saves time during panel build because the nuts stay captive while you torque the bus connections. The 3-pole configuration is typical for three-phase 400 V line protection feeding motor control centers, lighting panels, or sub-distribution boards.