The Siemens SENTRON 3VA2340-5JQ32-0HC0 is a 3-pole molded case circuit breaker rated 400 A at 40 °C, designed for line protection in distribution panels. Its interrupting capacity reaches 187 kA at 240 V and 121 kA at 415 V, with a 7.5 kA floor at 690 V — so it handles high-fault utility feeds without cascading upstream. The breaker ships with a factory-installed shunt trip (STL) and two auxiliary switches (HQ), and supports communication functions for integration into a monitored power system.
Breaking capacity and thermal derating
At 240 V the MCCB clears 187 kA — that's a very high rating for a 400 A frame, suited for service-entrance or main-tie applications where available fault current is high. At 415 V it still holds 121 kA, dropping to 75.6 kA at 500 V and 7.5 kA at 690 V. The thermal continuous rating is 400 A from 40 °C through 50 °C; above that it derates to 375 A at 55 °C, 350 A at 60 °C, 325 A at 65 °C, and 300 A at 70 °C. For a panel that runs warm — say 55 °C ambient inside the enclosure — you lose 25 A of headroom, so size the upstream transformer or bus accordingly.
Integrated accessories and communication
This variant comes with a shunt trip (STL) for remote tripping and two HQ auxiliary switches for status feedback — no separate add-on kit needed. It also includes an undervoltage release (voltage trigger) for undervoltage protection. Communication function is built in, so the breaker can report status and alarms to a BMS or PLC without an external gateway module. The base switch itself is order code 3VA2340-5JQ32-0AA0; the -0HC0 suffix adds the releases and aux switches.
Dimensions and panel fit
The breaker measures 248 mm high, 138 mm wide, and 110 mm deep. That 110 mm depth (4.33 in) is shallow enough for a 200 mm deep enclosure with room for rear bus connections. The 138 mm width (5.43 in) means it occupies three standard 45 mm pole spaces on a DIN rail — verify your backplate layout if swapping from a different frame. Operating temperature range is -25 °C to 70 °C; storage from -40 °C to 80 °C.