SENTRON 3VA2340-6JQ32-0KH0 — 400 A MCCB with 242 kA Breaking at 240 V
The Siemens SENTRON 3VA2340-6JQ32-0KH0 is a 3-pole molded case circuit breaker rated for line protection, carrying a continuous current of 400 A at 40 °C ambient and delivering a breaking capacity of 242 kA at 240 VAC — enough to handle high-fault utility feeds or transformer secondaries without cascading upstream. Rated current holds flat at 400 A from 40 °C through 50 °C, then derates to 375 A at 55 °C, 350 A at 60 °C, 325 A at 65 °C, and 300 A at 70 °C — useful when the breaker sits in a warm enclosure near other heat sources. Breaking capacity drops with system voltage: 187 kA at 415 V and 440 V, 121 kA at 500 V, and 7.5 kA at 690 V. That 690 V figure is the weak point — verify your fault current at that voltage level before specifying.
Trip Settings and Auxiliary Configuration
The electronic trip unit is adjustable from 80 A (initial value) to 400 A (full-scale), giving flexibility to match the protected conductor or load without swapping the breaker frame. Comes factory-fitted with 2 auxiliary switches plus 1 trip alarm switch (HQ design) and a shunt trip release (STL) for remote tripping — covers status feedback and emergency-off integration without adding modules later. A voltage-trigger function is present; undervoltage release is not included. Communication function is built in, so the breaker can report status and accept remote commands over the plant network.
Physical Fit and Panel Integration
Dimensions: 248 mm height, 138 mm width, 110 mm depth (9.76 × 5.43 × 4.33 in). Mounts on a DIN rail or direct panel surface — the 138 mm width is a standard 3-pole MCCB footprint, so it drops into existing SENTRON or comparable panel layouts without re-drilling. Maximum power loss is 96 W at rated load — account for that heat in enclosure sizing, especially if the breaker is grouped with other high-current devices.