What this 3VA1 frame breaker carries
The Siemens 3VA1125-3GD42-0AA0-ZD00 is a current-production IEC frame 160 molded-case circuit breaker, 4-pole, rated 25 A with a breaking capacity of 25 kA at 415 V (class N). It's built for line protection using a TM210 thermal-magnetic trip unit — fixed overload protection set at Ir = 25 A and fixed short-circuit protection at Ii = 12.8 x In. The N conductor is protected at 100%.
The Ii = 12.8 x In (about 320 A instantaneous) gives a high magnetic pickup, which avoids nuisance trips on motor inrush or transformer energization but still clears hard faults fast.
Where it fits — panel integration
The nut keeper kit (included per the OEM spec) helps when landing lugs in a high-vibration environment — keeps the hardware from backing off on a pump or conveyor line. The 100% N conductor protection means the neutral pole is fully rated, not reduced, so it's suited for 4-wire systems where neutral harmonics or unbalanced loads are a concern.