The Siemens SENTRON 3VA2340-6HL32-0JH0 is a 3-pole molded case circuit breaker rated for 400 A continuous current across the 40 °C to 50 °C ambient range — no derating needed in a standard 40 °C panel environment. At 415 V and 440 V it still holds 187 kA, dropping to 121 kA at 500 V and 7.5 kA at 690 V — the steep roll-off above 500 V means this breaker is primarily sized for 240–500 V distribution, not 690 V motor circuits. The basic switch assembly is order code 3VA2340-6HL32-0AA0 — the -0JH0 suffix adds the shunt trip and auxiliary contact block. Maximum power loss is 96 W — plan for that heat rejection inside the enclosure if the breaker is loaded near its 400 A rating continuously.
Thermal derating curve — where the 400 A rating holds and where it drops
At 55 °C it derates to 385 A, at 60 °C to 370 A, at 65 °C to 355 A, and at 70 °C to 340 A.
Physical fit — panel integration notes
The 138 mm width across three poles means a 4-pole version of the same frame would be roughly 184 mm. Mounting is via the rear panel or DIN rail adapter (not included in this variant). Allow the 96 W dissipation in the thermal budget; forced ventilation may be needed if the enclosure is sealed and loaded continuously.