The Siemens 3VA1020-3ED32-0JH0 is a 3-pole IEC frame 100 molded case circuit breaker with a 20 A fixed thermal-magnetic overload (Ir=20 A) and a fixed short-circuit pickup of 16 × In (320 A). Breaking capacity is class N at 25 kA / 415 V — enough for most downstream distribution panels in commercial or light industrial buildings where fault currents stay under that threshold. The integrated shunt trip (STL) operates on 110–127 V DC or AC 50/60 Hz, letting a remote E-stop or fire-alarm relay drop the breaker without pulling the handle.
What the ratings mean for fit
The 25 kA Icu at 415 V is the maximum short-circuit current the breaker can safely interrupt once. For a panel with a lower available fault current (say 18 kA), the same breaker still works — the rating is a ceiling, not a target. The fixed Ir=20 A means no adjustment dial; the breaker trips at 20 A continuous. The Ii=16 × In (320 A) short-circuit pickup is fixed, so it clears bolted faults fast but may nuisance-trip on high-inrush loads like small transformers if the inrush exceeds 320 A peak — check the load's inrush profile before specifying.