Siemens SENTRON 3VA2340-5HN32-0KH0 — 400 A MCCB, Line Protection, High Interrupting Capacity
The Siemens SENTRON 3VA2340-5HN32-0KH0 is a 3-pole molded case circuit breaker (MCCB) rated for 400 A continuous current at 40 °C, designed for line protection in distribution panels and industrial switchboards. It carries a 187 kA interrupting capacity at 240 VAC, dropping to 121 kA at 415 V and 440 V, 75.6 kA at 500 V, and 7.5 kA at 690 V — the high 240 V figure suits it for low-voltage main or feeder duty where fault current is substantial. The breaker includes a shunt trip release (STL) and is fitted with 2 auxiliary switches plus 1 trip alarm switch (HQ configuration), so it can report its status back to a PLC or SCADA system without an external interface module.
Interrupting Capacity and Selectivity Planning
The 187 kA at 240 V is the headline interrupting rating — this breaker can safely clear a fault at that level without upstream cascading, which matters when the transformer secondary is large or the service entrance is stiff. At 415/440 V (common for industrial motor control centers) the rating is still 121 kA, well above typical panel SCCR requirements. The 7.5 kA at 690 V is a derated value for 690 V systems; if your installation is at that voltage, verify the available fault current stays under that limit. Maximum power loss is 96 W — account for that heat in the enclosure ventilation calculation, especially if the breaker is enclosed without forced airflow.
Mounting and Panel Integration
Dimensions are 248 mm height, 138 mm width, 110 mm depth — a standard MCCB footprint for 400 A class. The 110 mm depth (4.33 in) is shallow enough to fit most 200 mm deep enclosures without crowding the gland plate. Three poles, so it occupies a 138 mm wide slot on the mounting plate. No undervoltage release is fitted (: No), so if your safety circuit requires a UVR, you will need to add one externally or specify a different variant. The breaker includes a trip indicator and a voltage trigger for local status.
Environmental and Derating
Continuous current holds at 400 A from 40 °C through 50 °C ambient. 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. Operating temperature range is -25 °C to +70 °C; storage range is -40 °C to +80 °C. If the breaker sits in a hot panel (e.g., near a transformer or in a sun-exposed enclosure), use the 55 °C or 60 °C column for sizing — do not assume full 400 A capability above 50 °C.