SENTRON 3VA1120-3EF36-0KC0: 20 A MCCB with 75.6 kA SCCR
The Siemens SENTRON 3VA1120-3EF36-0KC0 is a 3-pole molded case circuit breaker (MCCB) rated for line protection in distribution panels. Its headline interrupting capacity is 75.6 kA at 240 V — that means it can safely clear a fault up to that level without welding contacts or cascading upstream, which is the deciding spec for high-fault industrial services where a standard 10 kA or 25 kA breaker would fail coordination. At 415 V it still handles 52.5 kA, and at 690 V it holds 11.9 kA, so it covers low-voltage motor control centers and transformer secondaries across common global voltages. Rated current is 20 A continuously at 40 °C ambient, with full thermal rating holding through 55 °C before derating to 19 A at 60–70 °C. That gives you a solid 20 A handle for feeder circuits in warm enclosures without oversizing the frame. The 800 V rated insulation voltage (Ui) confirms it is suitable for 480 V and 600 V class systems with margin.
Auxiliaries and integration
Factory-fitted with a shunt trip (STL) auxiliary release and two HQ auxiliary switches — the STL lets you remotely trip the breaker via a control signal, which is standard for emergency-stop circuits or PLC-controlled load shedding. The two auxiliary switches provide status feedback (open/closed/tripped) to the control system. No undervoltage release or ground-fault monitoring on this variant; those are separate order codes if your spec requires them. Dimensions are 130 mm height, 76.2 mm width, 70 mm depth — a standard 3-pole MCCB footprint that fits SENTRON panelboards and most DIN-rail adapter plates. The supplied basic switch is order code 3VA11203EF360AA0, which is the internal switching mechanism; the complete unit ships as one assembly, no separate subcomponents to order.
Lifecycle and compliance
Maximum power loss is 12 W at rated load, which is typical for a 20 A MCCB frame and helps with enclosure thermal calculations. Operating temperature range is -25 °C to +70 °C; storage range is -40 °C to +80 °C.