The Siemens SENTRON 3VA1120-6EF32-0JA0 is a 3-pole molded case circuit breaker rated for 20 A continuous at 40 °C, with a TM240 thermal-magnetic release — meaning the thermal element handles overload protection and the magnetic element handles short-circuit interruption without electronic adjustment.
Panel fit and thermal derating
Dimensions are 70 mm deep, 76.2 mm wide, 130 mm high — a standard 3-pole MCCB footprint that mounts on DIN rail or panel-mount adapter, leaving room for adjacent breakers in a multi-pole distribution block. Thermal derating is flat at 20 A from 40 °C through 55 °C, then drops to 19 A at 60 °C and 65 °C, and holds at 19 A through 70 °C — minimal derating for a 20 A frame, which simplifies panel sizing in warm enclosures.