The ABB S203P-C25 is a 3-pole miniature circuit breaker rated 25 A with Trip Curve C, designed for DIN-rail mounting in distribution panels. It carries a 10 kA interrupting capacity at 277 V AC per pole, which means it can safely clear a fault up to 10,000 A without welding contacts or cascading failure upstream — a solid match for commercial and light industrial branch circuits where the available fault current stays under that threshold.
Curve C and selectivity
Trip Curve C means the magnetic trip fires at 5 to 10 times rated current (125–250 A for this 25 A unit). That's the standard choice for general-purpose loads like lighting, socket outlets, and small transformers — moderate inrush that Curve B would nuisance-trip on, but not the high-starting-current motors that call for Curve D. In a panel coordinated for Curve C downstream, this breaker holds selectivity with a 63 A or 80 A upstream Curve C MCB up to roughly 6 kA fault level, depending on the manufacturer's let-through chart.
Panel integration
Snaps onto standard 35 mm DIN rail per EN 60715. The 3-pole body occupies three modular units (17.5 mm each). Terminals accept up to 25 mm² conductor — solid or stranded — with a strip length of 12 mm. Busbar comb can be inserted from the top or bottom; the terminal screws are captive and require a Pozidriv #2 bit.