Motor protection breaker — 3VA2 frame, ETU860M trip unit
The Siemens 3VA2110-5MQ36-0HC0 is a 3-pole motor protection circuit breaker on the IEC frame 160 platform, rated In=100A with an ETU860M electronic trip unit covering LSIG (long-time, short-time, instantaneous, ground-fault) protection. Breaking capacity hits 55kA at 415V — class M on the 3VA2 scale, which means it clears high-fault scenarios on motor feeders without cascading upstream. The overload protection range Ir=40A...100A gives you a wide tap to match motor FLA, and the ground-fault element Ig=0.2...1 x In with adjustable time delay tg=0.05-0.8s covers sensitive earth-leakage coordination.
What the ratings mean for fit
The 55kA Icu @ 415V is the key coordination number — it tells you this breaker can interrupt a fault up to that level without needing a current-limiting fuse upstream. The ETU860M LSIG trip unit is programmable: Isd (short-time pickup) from 1.2 to 15x In, Ii (instantaneous) from 3 to 15x In. That range covers motor starting inrush (typically 6-8x FLA) without nuisance tripping, while still catching bolted faults. The shunt trip (STL) coil accepts 12-30V DC or 24V AC — common for remote trip from a safety relay or E-stop circuit. Two auxiliary switches (HQ) give status feedback to the PLC or SCADA.
Deployment context
This breaker mounts on a DIN rail in the motor control center or distribution panel. The 3VA2 frame size fits alongside other IEC 60947-2 devices for coordinated motor feeder protection. Typical deployment: protecting a 75-100A motor circuit on a 415V three-phase supply in a manufacturing plant, water treatment facility, or HVAC central plant.