What it is and what it does
The Siemens SENTRON 3VA2140-5HL36-0AA0 is a 3-pole molded case circuit breaker (MCCB) rated for 40 A continuous current, built around the ETU320 electronic trip unit for line protection duty. Its 40 A rating holds flat across the full ambient range from 40 °C to 70 °C, so no derating is needed in a warm panel — that is the number to match against your load. Breaking capacity runs from 187 kA at 240 V down to 3.7 kA at 690 V; at the common 415 V level it interrupts 121 kA, giving solid SCCR headroom for most industrial distribution panels.
Panel fit and integration
Mounts on a DIN rail or panel-mount baseplate. Dimensions are 105 mm wide × 181 mm high × 86 mm deep — the width is the critical number for multi-pole spacing in a distribution board. Front face carries IP40 protection.
What the ratings mean for your BOM line
Rated insulation voltage is 800 V, so the breaker is safe for 690 V systems with margin. The ETU320 release is an electronic trip unit with LSI curves (long-time, short-time, instantaneous) — not a thermal-magnetic, so coordination studies need the correct trip-characteristic data. Power loss is 1.6 W maximum — negligible for thermal budgeting in a multi-breaker panel, but worth noting if you are populating a sealed enclosure with many units. Operating temperature range is -25 °C to 70 °C; storage range is -40 °C to 80 °C. The storage limit governs handling and warehousing, not running conditions.