MCCB for high-fault panel applications
The Siemens SENTRON 3VA1120-6EF36-0JA0 is a 3-pole molded case circuit breaker rated for 20 A continuous current, with a line protection release (TM240) and a built-in shunt trip (STL). It's built to handle serious fault current: 220 kA at 240 V, 154 kA at 415 V, and 121 kA at 440 V — numbers that tell you this breaker is meant for high-available-fault-current panels where a standard MCCB would weld its contacts shut. The interrupting capacity at 690 V drops to 17 kA, so if you're on a 690 V system, check that the fault level stays under that.
Thermal derating and panel fit
This breaker holds its full 20 A rating up to 50 °C ambient. Above that it derates linearly: 19.2 A at 55 °C, 18.8 A at 60 °C, 18.4 A at 65 °C, and 18 A at 70 °C. If the panel runs hot — say next to a drive or inside a non-ventilated enclosure — you'll need to account for that drop. The case dimensions are 130 mm high by 76.2 mm wide by 70 mm deep, and it carries an IP40 front protection rating, so it's fine for general indoor panel mounting but not for washdown areas. No auxiliary contacts, no communication module, no undervoltage release — this is a bare-bones line-protection breaker with a shunt trip for remote opening.