MCCB for line protection — 80 A continuous, 75.6 kA interrupting
The Siemens 3VA1080-3ED36-0KH0 is a SENTRON molded case circuit breaker (MCCB) designed for line protection in distribution panels. It carries 80 A continuously at 40 °C ambient, with thermal derating to 74 A at 70 °C — the full curve matters when the panel runs hot. Interrupting capacity hits 75.6 kA at 240 V AC, dropping to 52.5 kA at 415 V and 32 kA at 440 V; at 500 V and 690 V it holds 7.5 kA. That's a strong SCCR for 240 V service, but at higher voltages the fault-current ceiling is lower — check your available fault current before specifying. Rated insulation voltage is 800 V, and the 3-pole form factor fits standard DIN-rail or panel-mount enclosures. The auxiliary switch complement — two auxiliary switches plus one trip alarm switch (HQ) — gives remote status feedback for PLC or SCADA integration. A shunt trip (STL) release is built in, so remote tripping is wired out of the box; undervoltage release is not fitted on this variant.
Thermal derating and power loss — panel-builder considerations
Maximum power loss is 19.2 W. In a sealed enclosure that adds up — account for it in the thermal budget alongside adjacent devices. The 80 A rating holds flat from 40 °C through 50 °C; above that it drops 1–2 A per 5 °C step. If the panel ambient sits at 55 °C, the breaker is good for 78 A; at 65 °C, 75 A. The trip indicator (mechanical flag) gives a quick visual on tripped state without needing to reset the handle — useful during fault isolation.