What the ratings mean for fit
The Siemens SENTRON 3VA2340-5HL42-0DC0 is a 4-pole molded case circuit breaker rated for 400 A continuous current at 40 °C, holding that rating through 50 °C before derating to 385 A at 55 °C and 340 A at 70 °C. At 240 V it interrupts 187 kA, at 415 V and 440 V it delivers 121 kA, at 500 V it provides 75.6 kA, and at 690 V it handles 7.5 kA — the breaking capacity drops sharply above 500 V, so verify the available fault current at your system voltage. The 400 A frame means this breaker is sized for main feeders or large motor branch circuits in industrial distribution. Designed for line protection, it includes an undervoltage release (UVR) and two auxiliary switches (HQ) for status feedback to a PLC or SCADA system. The 110 mm depth, 184 mm width, and 248 mm height fit standard panel layouts — measure your enclosure depth to confirm clearance for the 110 mm projection and the cable bending radius for 400 A terminations.
Panel integration and wiring notes
Mounts on a DIN rail or directly to a backplate. The 4-pole design requires four conductors for the main circuit plus control wiring for the undervoltage release and auxiliary switches. Power loss is 98.5 W maximum — account for this heat in the enclosure thermal calculation, especially when the breaker is loaded near its 400 A rating in a sealed cabinet.