MCCB for line protection — 80 A, 4-pole, TM240 trip
The Siemens 3VA1116-5FF46-0AA0 is a SENTRON molded case circuit breaker designed for line protection, carrying a rated current of 80 A across all four poles. The TM240 thermal-magnetic overcurrent release handles both overload and short-circuit events without external control power — the bimetal element tracks load heating, while the magnetic coil responds to instantaneous fault currents. Breaking capacity is voltage-dependent: 187 kA at 240 V, 121 kA at 415 V, 75.6 kA at 440 V, and 17 kA at both 500 V and 690 V, which covers most low-voltage distribution panels and motor control centers where the available fault current at the bus is known.
Thermal derating and panel integration
The breaker maintains its full 160 A current rating from 40 °C through 50 °C ambient, then derates to 158 A at 55 °C, 155 A at 60 °C, 153 A at 65 °C, and 150 A at 70 °C. That means in a sealed enclosure with internal temperature rise, you lose only about 6 % of capacity at the 70 °C ceiling — usable headroom for a densely packed panel. Dimensions are 130 mm high, 101.6 mm wide, and 70 mm deep; the 4-pole width (101.6 mm) matches the standard SENTRON 4-pole footprint, so it drops onto a DIN rail or mounting plate in the same cutout as other 3VA frames. Front-side IP40 protection keeps dust and tools out of the mechanism; the rear terminals remain accessible for busbar or cable connection per the panel builder's wiring practice.
What the ratings mean for fit
The 80 A rating is the continuous current the breaker carries without tripping — sized for a feeder or a large motor circuit where the full-load amps sit below that mark. The TM240 designation on the overcurrent release means the thermal element is calibrated for a 240 A frame; the 80 A rating is set by the installed rating plug or fixed trip setting inside that frame. No undervoltage release, no shunt trip, no communication function, and no ground-fault monitoring are built in — this is a plain line-protection MCCB, not a multifunction power breaker. Rated insulation voltage is 800 V, so it is suitable for 480/277 V and 600 V systems with margin. Maximum power loss at rated load is 38 W per pole, which factors into enclosure ventilation calculations when multiple breakers are ganged.