What it is and what it does
The Siemens 3VA1132-4EF36-0DH0 is a SENTRON molded case circuit breaker (MCCB) built for line protection in distribution panels. It's a 3-pole unit rated at 32 A continuous current at 40 °C, with a rated insulation voltage of 800 V — comfortable for 480 V and 600 V class systems. Where this breaker earns its keep is the interrupting capacity: 121 kA at 240 V AC, 75.6 kA at 415 V, 52.5 kA at 440 V, and still 11.9 kA up at 690 V. That's serious fault-current muscle for a 32 A frame — means it can sit downstream of a big transformer without worrying about cascading failure.
Thermal performance and derating
The breaker holds its full 32 A rating from 40 °C up through 50 °C. At 55 °C it derates to 31 A, at 65 °C to 30 A, and at 70 °C it still carries 30 A. That's a shallow derating curve — good for a warm panel or a cabinet sitting next to a motor drive. Operating temperature range is -25 °C to 70 °C, storage from -40 °C to 80 °C. Max power loss is 13.1 W — modest enough that you don't need forced cooling in a standard enclosure.
Built-in accessories
This version ships with an undervoltage release (UVR) and a complement of auxiliary switches: two auxiliary switches plus one trip alarm switch (HQ). The UVR means the breaker will drop out if control voltage is lost — useful for emergency-stop circuits or safety interlocks where you want the load isolated on power loss. No ground-fault monitoring on this variant, and no communication module. It's a straight line-protection breaker with mechanical indication — the trip indicator is present, so you get a visual flag on the front when it's tripped.
Panel fit and dimensions
The breaker measures 130 mm high, 76.2 mm wide, and 70 mm deep. That's a standard 3-pole MCCB footprint — mounts on a DIN rail or directly to a backplate with the usual screw terminals. The supplied basic switch is order code 3VA11324EF360AA0, so if you need a replacement switch mechanism, that's the part to reference.
Lifecycle and sourcing
For a BOM freeze or a panel build, this breaker is a straight drop-in for any 32 A, 3-pole MCCB slot in a SENTRON lineup. If you're cross-referencing from another brand, the interrupting capacities at your system voltage are the key check — at 480 V it's still well above typical available fault current.