What this MCCB is and what it does
The Siemens SENTRON 3VA2040-8HM46-0AA0 is a 4-pole molded case circuit breaker (MCCB) rated for 40 A continuous current, with an adjustable thermal-magnetic trip unit covering 60 A to 480 A — meaning you set the actual protection threshold anywhere in that band to match the downstream load, not just the fixed 40 A frame rating. Its interrupting capacity reaches 440 kA at 240 V AC, 330 kA at 415 V and 440 V, 220 kA at 500 V, and 52.5 kA at 690 V — so it handles high-fault-current scenarios typical of industrial distribution panels without needing an upstream current-limiting fuse. Designed for line protection (not motor or generator protection), this MCCB integrates ground-fault monitoring via summation current sensing on L + N conductors, which is useful for detecting leakage in four-wire systems without a separate GFCI module.
Panel fit and dimensions
The breaker measures 181 mm high, 140 mm wide, and 86 mm deep — a standard SENTRON 3VA frame size that mounts directly onto a DIN rail or panel-mount adapter without adaptor plates for most enclosures.
Environmental and compliance
Operates from -25 °C to 70 °C ambient and stores from -40 °C to 80 °C, with no derating of the 40 A continuous rating across the full operating range (tested at 40 °C through 70 °C). Maximum power loss is 1.2 W at rated current — negligible for panel thermal budgeting. Rated insulation voltage is 800 V. RoHS and REACH declarations available on request.