What the ratings mean for your panel
The Siemens SENTRON 3VA1332-6EF32-0AA0 is a 3-pole molded case circuit breaker (MCCB) rated for line protection, carrying 320 A continuously at 40 °C and holding that same rating through 50 °C — only then does it begin a gentle derating curve: 313 A at 55 °C, stepping down to 292 A at 70 °C. That means in a warm enclosure you lose only about 9 % of capacity at the upper end, which gives you headroom for a crowded panel without oversizing the frame. Breaking capacity is where this MCCB earns its keep for high-fault installations. At 240 V it interrupts 220 kA; at 415 V and 440 V it still holds 154 kA, dropping to 121 kA at 500 V and 17 kA at 690 V. Those numbers tell you the 3VA1332 can sit downstream of a large transformer or in a heavy industrial service entrance without needing a current-limiting fuse upstream to protect it — the breaker itself handles the fault. The overcurrent release is a TM240 — a thermal-magnetic fixed-trip design at 240 A, which means the breaker's thermal element responds to sustained overloads while the magnetic element catches short-circuits. No electronic trip unit, no communication module, no ground-fault monitoring. It is a straightforward, field-reliable choice for a feeder or main where you do not need adjustable trip curves or remote signaling.
Lifecycle and sourcing reality
Rated insulation voltage is 800 V, and the front face carries IP40 protection — enough for a clean indoor panel but not for washdown zones. The breaker measures 248 mm high by 138 mm wide by 110 mm deep, which is the standard 3VA frame footprint; it drops into the same mounting pattern as other 3VA three-pole breakers in this frame class.
Integration notes
Mounts on a DIN rail or direct-panel via the 3VA base plate. The 138 mm width occupies three 45 mm pole spaces — standard for a 3-pole MCCB in this class. Power loss at full rated current is 80.1 W maximum, so factor that into your enclosure thermal calculation; a 320 A breaker dumping 80 W inside a sealed cabinet raises the internal temperature by several degrees and shifts the derating curve you saw above. No undervoltage release, no shunt trip, no communication function, and no voltage-trigger accessory are included on this variant. If your circuit requires remote trip or status feedback, you will need to add the appropriate accessory module from the 3VA system — the basic breaker is a standalone thermal-magnetic device with no auxiliary contacts or trip indicator.