The Siemens SENTRON 3VA1120-4EE32-0AA0 is a 3-pole molded case circuit breaker (MCCB) rated 20 A at 40 °C, designed for line protection in distribution panels. It carries a TM220 thermal-magnetic release — the thermal element handles overloads, the magnetic element clears short-circuits — and is rated for an insulation voltage of 800 V. The 121 kA breaking capacity at 240 V AC means it can safely interrupt fault currents up to that level without upstream devices needing to intervene, which simplifies coordination in high-fault installations like industrial switchboards or mains feeders.
Breaking capacity across voltages
Breaking capacity drops as voltage rises: 75.6 kA at 415 V, 52.5 kA at 440 V, and 11.9 kA at both 500 V and 690 V. At 690 V the 11.9 kA figure is the limiting factor — verify the available fault current at the point of installation before specifying this breaker for a 690 V feeder. The 3-pole frame and 70 mm depth fit standard panel layouts; front-side IP40 protection suits indoor enclosures where tools or fingers won't contact live parts.
Integration notes
Mounts on a DIN rail or panel-mount base in a standard distribution board. The 76.2 mm width (3 in) occupies three 18 mm module spaces on a DIN rail — plan for that footprint during panel layout. No undervoltage release, no shunt trip, no communication module on this variant; if remote tripping or status feedback is needed, specify a different 3VA variant with those accessories. The TM220 release is fixed — not field-interchangeable — so confirm the 20 A rating matches the protected circuit before installation.