The Siemens 3VA1340-5EE42-0AA0-ZD00 is a 4-pole IEC frame 400 molded case circuit breaker with a 55 kA Icu at 415 V, placing it in breaking capacity class M. The TM220 thermal-magnetic trip unit provides adjustable overload protection from 280 A to 400 A, with a fixed short-circuit pickup at 10 x In. This variant includes an ATFM (Advanced Trip Function Module) and is configured with the N conductor unprotected — a detail that matters when coordinating with downstream distribution boards where the neutral is not switched.
What the Ratings Mean for Fit
The 55 kA Icu at 415 V is the ultimate short-circuit breaking capacity — the maximum fault current the breaker can safely interrupt once. For selectivity studies, the 10 x In instantaneous pickup (Ii = 4000 A) coordinates with downstream 50 kA-rated MCCBs in a typical 415 V distribution panel. The adjustable Ir band (280–400 A) lets you match the breaker to the actual continuous load without swapping the trip unit, which is useful when the same frame size serves multiple transformer or feeder ratings.
Deployment Context
This 4-pole breaker mounts in a standard IEC distribution panel or switchboard — the frame 400 footprint is common across the 3VA1 platform. The nut keeper kit for DC Power OEM in China indicates a specific accessory provision for DC-side applications, though the breaker itself is an AC-rated device per the IEC 60947-2 standard that governs its 55 kA rating. Panel builders should verify the neutral conductor unprotected configuration against the system earthing arrangement before wiring.