What this MCCB carries — and what it doesn't
The 3VA1163-6MH32-0JA0 is a 3-pole IEC frame 160 MCCB from the Siemens 3VA1 series, rated 63 A with a TM120M thermal-magnetic trip unit. The magnetic short-circuit pickup is adjustable from 5 to 15× In. Breaking capacity is class H: Icu = 70 kA at 415 V AC. That is the maximum fault current the breaker can interrupt once and still be functional. This variant ships without overload protection — the TM120M provides short-circuit protection only, with the thermal element omitted. That's deliberate: it's meant for starter-protection duty where the upstream overload relay handles the thermal curve. Pair it with a properly sized contactor and overload for motor branch circuits. The integrated shunt trip (STL) operates on 110–127 V DC or AC, 50/60 Hz. That's a remote-trip coil — energize it and the breaker opens instantly. Typical use: emergency-stop circuit, fire-alarm shunt, or a PLC-driven safe-state signal that kills power to the motor control center. A nut keeper kit is included in the box — that's the hardware to retain the terminal nuts on the line/load lugs so vibration on a mill or conveyor frame doesn't back them off. Built for the pit, not the panel shop.
Where it fits in the panel
The 3VA1 frame 160 mounts on a standard DIN rail or can be screw-fixed to a backplate. The 3-pole footprint is compact for the 70 kA rating — roughly the same width as a standard 160 A frame. Leave clearance above and below for the arc-chute exhaust; Siemens specifies minimum 100 mm free air for the gas vent. The shunt trip terminals are separate from the main power lugs. Verify the control voltage matches your panel's 110–127 V supply before energizing.