The SENTRON 3VA2125-8KQ46-0AA0 is a 4-pole molded case circuit breaker (MCCB) rated for line protection, carrying a continuous current Iu of 25 A that holds flat across the full 40 °C to 70 °C operating range — no derating needed as the panel warms up, which is unusual for a compact-frame MCCB. The ETU860 electronic trip unit gives you adjustable long-time delay (tr) from 0.5 s to 25 s and N-conductor protection configurable OFF or 40 % to 160 % of the phase setting, so it handles both 3-phase and 3-phase + N distribution without a separate neutral breaker. Breaking capacity is the headline figure here: 440 kA at 240 V, 330 kA at 415 V and 440 V, 220 kA at 500 V, and 53 kA at 690 V. The IP40 front protection means it's splash-resistant from the front but not sealed; install it in a clean indoor panel, not a washdown zone.
The built-in communication function means it can integrate with higher-level monitoring systems via the SENTRON communication modules — useful for energy management or remote trip indication in a BMS or SCADA environment.
The 3VA2163-8JQ32-0AA0 is the nearest functional sibling — same 4-pole frame, same ETU860 trip unit family, but rated for a higher continuous current. The deciding factor between them is the load current: the 3VA2125-8KQ46-0AA0 tops out at 25 A, while the 3VA2163-8JQ32-0AA0 carries a higher rating. If your BOM specifies 25 A, this is the correct order code; the sibling won't drop in without rewiring the load side.
Deployment context
Ground-fault monitoring via summation current formation (L + N) is built into the ETU860 — no external GFCI module needed for residual current detection.