What it is and what it does
The Siemens 3VA1180-4EF32-0DA0 is a SENTRON molded case circuit breaker (MCCB) for line protection — the main disconnect and fault interrupter in a distribution panel or motor control center. It's a 3-pole unit rated for 80 A continuous current at up to 50 °C ambient, with a TM240 thermal-magnetic overcurrent release that handles both overload and short-circuit protection in one package. The interrupting ratings are what decide where this breaker fits in a fault-current study: 121 kA at 240 V AC, 75.6 kA at 415 V, 52.5 kA at 440 V, and 11.9 kA at 690 V. That 121 kA figure at 240 V means it can safely clear a bolted fault on a high-capacity transformer secondary without the arc flashing over — a requirement for service-entrance or main-breaker positions in large commercial or light industrial panels.
Thermal derating and real-world current
The 80 A rating holds flat from 40 °C through 50 °C ambient. Above that it starts to step down: 76.8 A at 55 °C, 75.2 A at 60 °C, 73.6 A at 65 °C, and 72 A at 70 °C. If this breaker lives in a hot enclosure — say a non-ventilated panel next to a drive — the 72 A ceiling at 70 °C is the number to size against, not the nameplate 80 A.
What's built in and what's not
This version ships with an undervoltage release (UVR) fitted — part of the auxiliary release design. That means the breaker will trip if control voltage drops below the release threshold, which is useful for emergency-stop circuits or undervoltage protection on motor loads. There's no auxiliary contact block, no ground-fault monitoring, no phase-failure detection, and no communication function. It's a straight line-protection breaker with a UVR and nothing else on the accessory rail. The integrated auxiliary trip is specified as order code 3VA9608-0BB25 — that's the factory-fitted UVR module. If you need to add auxiliary contacts or a shunt trip later, those are separate add-on accessories that mount to the breaker's side slots.
Panel fit and mounting
Dimensions are 130 mm high, 76.2 mm wide, 70 mm deep. The 76.2 mm width is a standard 3-pole MCCB footprint — it drops into a panel that was laid out for a SENTRON 3VA frame without re-drilling the mounting plate. IP40 on the front face means it's protected against tools and wires >1 mm, but not against water ingress; keep it inside a closed enclosure.