The Siemens 3VA2025-5HN32-0AH0 is a 3-pole IEC frame 100 molded case circuit breaker with a 55 kA breaking capacity at 415 V (class M). Overload protection Ir is adjustable from 10 A to 25 A; short-circuit protection Isd ranges from 1.5 to 10 times Ir, and the instantaneous pickup Ii is fixed at 12 times In.
The ETU350 LSI trip unit gives you selective coordination capability. The short-time delay (S) function lets you set Isd with a time delay so that a downstream breaker clears a fault first, keeping this breaker closed and upstream loads online. This is essential for a selective distribution scheme — without it, a fault on a branch trips the main and takes down half the plant. The 25 A In with Ir adjustable down to 10 A means this breaker covers a wide range of load sizes from a single frame. You can set it for a 10 A lighting panel or a 25 A motor feeder without changing hardware. The nut keeper kit is a small but appreciated detail — it prevents the mounting nuts from backing off under vibration, common in panels near compressors or conveyors.