What this MCCB is and what it does
The Siemens 3VA1080-3ED36-0AC0 is a SENTRON molded case circuit breaker (MCCB) built for line protection — the primary feeder or branch protection in a distribution panel. It's a 3-pole unit rated 80 A at 40 °C, with a TM210 thermal-magnetic trip unit that handles both overload (thermal) and short-circuit (magnetic) events. The 75.6 kA interrupting rating at 240 V gives it serious fault-clearing headroom for high-available-fault-current installations like a main service entrance or a large motor control center bus. No communication module, no ground-fault monitoring, no undervoltage release — this is a straightforward, non-communicating breaker. The auxiliary switch bay is populated with two HQ auxiliary switches (form C), which is enough for status feedback to a PLC or a remote indication lamp. The insulation voltage is rated 800 V, so it's comfortable on 480/277 V and 600 V systems.
Breaking capacity and thermal derating — the numbers that matter
The interrupting capacity drops as system voltage rises: 75.6 kA at 240 V, 52.5 kA at 415 V, 32 kA at 440 V, and 7.5 kA at both 500 V and 690 V. That 7.5 kA at 690 V is the floor — verify it against your available fault current if you're running a 690 V drive bus or a mining distribution system. Thermal derating is minimal up to 50 °C — it holds 80 A flat. At 55 °C it drops to 78 A, at 65 °C to 75 A, and at 70 °C to 74 A. If your panel ambient runs hot (say, a non-climate-controlled enclosure in a foundry or a solar combiner box), that 74 A at 70 °C is the number to size against, not the 80 A nameplate. Maximum power loss is 19.2 W — that's the heat the breaker dumps into the enclosure, so factor it into your thermal budget.
Panel fit and mounting
Width is 76.2 mm (3 in), depth is 70 mm (2.76 in), height is 130 mm (5.12 in). That 3-inch width per pole is standard for SENTRON 3VA MCCBs — it occupies three 1-inch spaces on the DIN rail or the mounting plate. The breaker accepts both front-connection and rear-connection lug kits (not included), and the TM210 trip unit is field-interchangeable if you need to change the rating plug later.