SENTRON 3VA1140-5EF32-0BC0 — 40 A MCCB for Line Protection
The Siemens SENTRON 3VA1140-5EF32-0BC0 is a 3-pole molded case circuit breaker (MCCB) rated at 40 A continuous current, designed for line protection in distribution panels. Its breaking capacity reaches 187 kA at 240 VAC, dropping to 121 kA at 415 VAC and 75.6 kA at 440 VAC — figures that govern selectivity coordination with downstream breakers. At 500 V and 690 V the interrupting rating holds at 17 kA, so this unit suits 400 V class systems where high fault current is expected at the service entrance or main switchboard. Rated current holds at 40 A from 40 °C through 50 °C ambient, then derates gradually: 39 A at 55–60 °C, 38 A at 65 °C, and 37 A at 70 °C. The maximum operating temperature is 70 °C, with storage range from -40 °C to 80 °C. Power dissipation at rated load is 13.3 W — a figure to include in enclosure thermal calculations when grouping several breakers. This MCCB ships with an undervoltage release (UVR) and two auxiliary switches (HQ design) factory-fitted. The UVR trips the breaker when control voltage drops below a set threshold — common in emergency-stop or undervoltage protection schemes. The auxiliary switches provide status feedback (open/closed/tripped) to a PLC or indication lamp without requiring a separate contactor block. Rated insulation voltage is 800 V.
Integration — Panel Fit and Wiring Notes
Dimensions are 130 mm high, 76.2 mm wide (3 inches), and 70 mm deep. The 3-pole footprint matches standard SENTRON 3VA panel cutouts and busbar systems. The breaker accepts screw-clamp terminals for cable or busbar connection; the UVR coil terminals are separate and polarity-sensitive if DC-supplied. Mounting is screw-fixed to a mounting plate or DIN rail adapter (not included).