What this 3VA2 breaker brings to the panel
The Siemens 3VA2340-6JP42-0AJ0 is a 4-pole IEC frame 400 circuit breaker with an 85 kA breaking capacity at 415 V — class H, meaning it handles high fault currents common in industrial distribution without needing a current-limiting upstream device. The ETU550 trip unit gives you LSI protection: long-time (overload) adjustable from 160 A to 400 A, short-time (selective) from 0.6x to 10x In, and instantaneous from 1.5x to 10x In. That adjustable short-time delay is what lets you coordinate downstream breakers for selectivity — a key requirement for plant engineers who want only the faulted branch to open, not the whole feeder. The N-conductor protection is adjustable from OFF to 100%, so you can match the neutral sizing to the load — useful on 4-wire systems where the neutral carries harmonics from single-phase loads. The built-in 2 auxiliary changeover switches and 1 trip alarm changeover switch give remote status without adding external relays, which saves DIN rail space and wiring time.
Integration notes for panel OEMs and field installers
Mounts on a standard DIN rail in the enclosure — the 4-pole form factor takes up four module widths. The nut keeper kit (included per the description) keeps the busbar screws from dropping into the panel during assembly, a small but real time-saver on a production line. For commissioning engineers: the ETU550 is field-adjustable; the rotary dials for Ir, Isd, and Ii are accessible without removing the cover, so you can dial in the coordination study values on-site with a screwdriver. No special software needed.