What this MCCB is and what it does
The Siemens SENTRON 3VA2140-5HL32-0AB0 is a 3-pole molded case circuit breaker (MCCB) rated for 40 A continuous current across the full 40 °C to 70 °C ambient range — no derating needed up to that ceiling. It carries a 187 kA interrupting capacity at 240 VAC and 121 kA at 415/440 VAC, which puts it in the high-fault category for industrial distribution panels and motor control centers where available fault current is significant. The ETU320 electronic trip unit provides adjustable overload and short-circuit protection curves, a step up from fixed thermal-magnetic releases for coordination selectivity.
Breaking capacity — what the numbers mean
The 187 kA at 240 VAC and 121 kA at 415 VAC are the ultimate short-circuit breaking capacities (Icu) per IEC 60947-2. At 500 VAC it still clears 75.6 kA, and at 690 VAC the rating drops to 3.7 kA — a steep fall that reflects the arc-extinction challenge at higher voltages. For a 480 VAC panel (common in North America), the 75.6 kA at 500 VAC is the closest reference; for 400 VAC systems (Europe/Asia), the 121 kA at 415 VAC applies. The rated insulation voltage is 800 V, so the breaker is electrically rated for 690 VAC systems but with the interrupting capability at that voltage confirmed at 3.7 kA.
Trip unit and auxiliary configuration
The ETU320 electronic trip unit is the overcurrent release on this variant. It supports LSI protection (long-time, short-time, instantaneous) with adjustable pickups and time delays, which is what you need for selective coordination downstream of a transformer or upstream of feeder breakers. The breaker ships with two HP auxiliary switches built in — no separate add-on module required for status feedback to a PLC or SCADA. The basic switch order code is 3VA21405HL320AA0, which is the internal switching mechanism; the full breaker includes it. There is no undervoltage release, no ground-fault monitoring, and no communication function on this order code — it is a straight power distribution breaker.
Physical fit and panel integration
Dimensions are 105 mm wide, 181 mm tall, and 86 mm deep. The 105 mm width is standard for a 3-pole SENTRON 3VA2 frame — it fits the same mounting footprint as other 3VA2 breakers in the same frame size. Front IP40 protection means it is suitable for enclosed panel mounting where tools are required to access live parts; no washdown rating. The breaker is designed for screw-mounting to a backplate or mounting plate, not DIN rail. Operating temperature range is -25 °C to 70 °C, storage from -40 °C to 80 °C.