What this MCCB carries
The Siemens 3VA1112-5MH36-0AG0 is a 3-pole molded case circuit breaker on the 3VA1 platform, IEC frame 160, rated In=125A with a breaking capacity class M delivering Icu=55kA at 415 VAC. That 55 kA interrupting rating means it can clear a bolted fault up to that level without self-destructing or cascading the arc upstream — critical for panel SCCR coordination when the transformer or feeder can push that much current.
Starter protection and short-circuit settings
This breaker ships with a TM120M release — a thermal-magnetic trip unit sized for motor starter protection. The thermal element provides overload protection, though the description explicitly notes this variant is configured without overload protection, relying instead on the upstream starter's overload relay. The magnetic short-circuit pickup Ii is adjustable from 5 to 15 times In (625 A to 1875 A), letting you dial in the instantaneous trip threshold to coordinate with the motor inrush and downstream cable protection.
Auxiliary and alarm switching
Factory-fitted with one auxiliary switch (HP) and one trip alarm switch (HP). The auxiliary signals the breaker's open/closed position to a PLC or status lamp; the trip alarm latches on a fault trip (short-circuit or overload) and stays closed until manually reset — essential for remote fault annunciation on an unattended line.
Connection and panel fit
Terminated via clamp connections — box-type lugs that accept aluminum or copper conductors without compression lugs. The 3VA1 frame mounts on a DIN rail or directly to a backplate; the 160 frame size fits standard MCCB panel cutouts and busbar riser spacing.