What this 40 A MCCB delivers — and where the ratings matter
The Siemens SENTRON 3VA2040-6HL36-0AA0 is a 3-pole molded case circuit breaker rated for 40 A continuous current with no derating all the way up to 70 °C ambient — same 40 A at 40 °C, 55 °C, even 70 °C. That means you size the breaker for the load, not the panel temperature. Its interrupting capacity hits 242 kA at 240 V AC and 187 kA at 415 V AC. At 690 V AC it still clears 3 kA. Those numbers cover high-fault utility feeds and transformer secondaries — the 242 kA figure is what you need for a 240 V service entrance or a large distribution board where the available fault current is serious. The ETU320 electronic trip unit gives you adjustable thermal and magnetic protection curves for the line protection version. No voltage trigger, no ground-fault monitoring, no communication function — this is a straight distribution breaker, not a power monitor.
Panel fit — dimensions and mounting
At 105 mm wide, 181 mm tall, and 86 mm deep, this breaker fits standard SENTRON panel footprints. The IP40 front protection means it's fine inside a closed enclosure — no special sealing needed for the operator face. Rated insulation voltage is 800 V, so it's comfortable on 690 V line-to-line systems with headroom. Maximum power loss at rated current is 2.2 W — negligible for thermal budgeting inside a panel.