The Schneider Electric G12E4F20 is a GoPact MCCB 125 molded case circuit breaker, 4-pole, rated 20 A at 40 °C with a TM-D thermal-magnetic trip unit.
Above that, thermal derating applies per the LI curve. For selectivity studies, this is a Category A breaker — no intentional short-time delay, so it trips instantaneously on magnetic pickup. The thermal element tracks RMS heating, so it handles motor inrush without nuisance tripping as long as the starting current stays within the time-current curve. The magnetic pickup is fixed, not adjustable — verify coordination with downstream devices before committing the BOM line. Rated insulation voltage (Ui) is 440 V AC, and the operational voltage (Ue) is 415 V AC — this breaker is specced for 400 V class distribution panels common in European and Asian installations. Mechanical durability is 30,000 cycles; electrical durability is 8,000 cycles at rated current and voltage. That's typical for a distribution breaker — not a switching device for frequent load cycling, but fine for infrequent manual isolation and automatic fault clearing.
Connection pitch is 25 mm between poles, matching standard busbar spacing. Screw terminals accept copper or aluminium conductors; front-facing connections on both sides simplify panel wiring and busbar runs. IP20 finger-safe protection on the front face — suitable for enclosed panel use only.