The Siemens 3VA1020-4ED36-0HH0 is a 3-pole SENTRON molded case circuit breaker (MCCB) rated for continuous current of 20 A across the 40 °C to 55 °C band, derating to 19 A at 60 °C through 70 °C. That thermal stability means it holds its full rating in a warm panel without forced cooling — a common concern when breakers are ganged on a DIN rail. Breaking capacity is the headline: 121 kA at 240 V, 75.6 kA at 415 V, 52.5 kA at 440 V, and still 11.9 kA at 500 V and 690 V. Trip indicator is present for quick visual fault isolation during a line-down event.
Front-face protection class IP40 means it's splash-protected against tools and fingers in a dry enclosure interior, but not for washdown. Maximum power loss is 12 W — negligible for thermal budget in a ventilated panel, but worth checking if the breaker is sealed in a non-vented enclosure with other heat sources.
This is a straight thermal-magnetic breaker — no electronic trip, no Modbus, no auxiliary power supply. If your spec calls for those, you're looking at a different 3VA variant.