The Siemens SENTRON 3VA2340-5JQ32-0DA0 is a 3-pole molded case circuit breaker rated for 400 A continuous current, built around the ETU560 electronic trip unit for line protection. It carries a 187 kA interrupting capacity at 240 V and 121 kA at 415 V — numbers that tell you this breaker handles high-fault utility feeds without cascading upstream. The 800 V rated insulation voltage gives it headroom for 480 V and 600 V class systems common in North American and European industrial panels.
Ratings and what they mean for the panel
Rated continuous current holds at 400 A up to 50 °C ambient — that's the full frame rating without derating in a typical ventilated enclosure. Above that it steps down: 375 A at 55 °C, 350 A at 60 °C, 325 A at 65 °C, and 300 A at 70 °C. If your panel runs hot near the top of the gland plate, factor the 55 °C or 60 °C row into the BOM, not the 400 A nameplate. Interrupting capacity drops with system voltage: 187 kA at 240 V, 121 kA at 415 V and 440 V, 75.6 kA at 500 V, and 17 kA at 690 V. That 17 kA at 690 V is the number to check if this breaker lands on a 690 V mining or marine distribution bus — it's still adequate for most downstream subfeeds but not for a main with high fault current. The ETU560 electronic trip unit provides adjustable long-time, short-time, instantaneous, and ground-fault protection curves. Ground-fault monitoring uses summation current formation on the L-conductor — it detects leakage without a separate neutral CT. Communication function is built in, so the breaker can report status and trip events over the plant network without an add-on module.
Panel fit and integration
Dimensions are 248 mm high, 138 mm wide, 110 mm deep. Mounts on a DIN rail or direct panel-mount via the base. No auxiliary contact version is fitted from the factory, but the slot accepts the 3VA9608-0BB25 auxiliary trip if you need remote status later. Power loss at full load is 98.5 W maximum — that's the heat you need to vent. In a multi-breaker lineup, sum the losses and size the enclosure ventilation accordingly. Operating temperature range is -25 °C to 70 °C; storage range is -40 °C to 80 °C, so it can sit in an unheated warehouse through winter without damage.