Siemens SENTRON 3VA2340-7HL32-0DH0 — 400 A MCCB with Undervoltage Release
The Siemens SENTRON 3VA2340-7HL32-0DH0 is a 3-pole molded case circuit breaker (MCCB) rated for 400 A continuous current, designed for line protection in distribution panels. Its interrupting capacity reaches 330 kA at 240 V and 242 kA at 415 V and 440 V, dropping to 187 kA at 500 V and 7.5 kA at 690 V — the 690 V figure is the one that governs high-voltage industrial feeds, so verify your fault level against that number if your system runs at 690 V line-to-line. The breaker carries an undervoltage release (UVR) as the auxiliary release type, plus two auxiliary switches and one trip alarm switch (HQ). The UVR trips the breaker when supply voltage drops below a threshold — useful for preventing motor re-acceleration after a sag or for coordinated load shedding. The trip indicator on the front confirms whether the breaker opened on fault or manual command. Thermal derating is flat at 400 A from 40 °C through 50 °C, then steps down: 385 A at 55 °C, 370 A at 60 °C, 355 A at 65 °C, and 340 A at 70 °C. If your panel ambient runs above 50 °C, the continuous current you can count on is the derated value, not the nameplate 400 A. Maximum power loss is 98.5 W, which factors into enclosure thermal calculations.
Panel Fit and Integration
Dimensions are 248 mm high, 138 mm wide, and 110 mm deep. The 3-pole footprint matches standard Siemens SENTRON 3VA mounting patterns, so it drops into existing panel cutouts and busbar arrangements for the series. The undervoltage release and auxiliary switch block add depth on the side — account for wiring clearance when laying out the enclosure.