What this 3VA1 MCCB delivers
The Siemens 3VA1020-3ED32-0AA0-ZD00 is a 3-pole IEC frame 100 molded-case circuit breaker in breaking capacity class N, rated Icu=25kA at 415 VAC. The TM210 trip unit gives fixed thermal-magnetic overload protection: Ir=20 A fixed, Ii=16 x In (320 A magnetic instantaneous). No adjustment dials on the overload or short-circuit pickup — this is a fixed-setting breaker, so the BOM line is locked once specified.
The nut keeper kit (included per the order-code suffix) secures the line-side and load-side terminals for DC Power OEM builds in China; if you are wiring into a panel with ring-tongue or fork terminals, the keeper prevents nut spin-out during torque-down. The TM210 trip is thermal-magnetic, so no auxiliary power is needed for the protection element — it is self-powered from the line current.