The SOL40F3A400 is a 3-pole molded-case circuit breaker from Schneider Electric's EasyPact Solar line, built for solar distribution and general 800 V AC power distribution.
Push the ambient higher and you derate; the trip unit's thermal memory means it tracks past heating, so repetitive overloads close to the threshold accumulate. Insulation voltage (Ui) is 1250 V AC, operational voltage (Ue) is 800 V AC 50/60 Hz — both per EN/IEC 60947-2. The IP20 finger-safe front keeps accidental contact out but isn't rated for washdown — this lives inside an enclosure. Mounts fixed to a backplate with a 40 mm pole pitch. Screw terminals front-connected both top and bottom. Toggle control, horizontal or vertical mounting. At 205 mm tall, 120 mm wide, 105 mm deep, it needs a solid backplate and enough swing clearance for the toggle.
Durability and thermal budget
Mechanical endurance is 20,000 cycles; electrical endurance at rated 800 V and 400 A is 4,000 cycles — that's the contact wear life under load. Power dissipation is 40 W per pole, so 120 W total through the breaker at full rated current. That heat has to leave the enclosure; factor it into your panel thermal calculation.
Listed as current production. No end-of-life notice or successor identified.