The ABB S203P-B6 is a 3-pole miniature circuit breaker from the S200P series, rated at 6 A with a Trip Curve B characteristic. It mounts on a standard DIN rail and provides overcurrent and short-circuit protection for branch circuits up to 277 V AC. The 10 kA interrupting rating at 277 V AC means this MCB can safely clear a fault up to 10,000 A without welding its contacts or cascading damage upstream — sufficient for most commercial and light industrial panelboards where the available fault current stays below that threshold.
Trip Curve B — what it means for the load
Trip Curve B means the magnetic trip fires at 3 to 5 times rated current (18–30 A for this 6 A unit). That makes it the right choice for resistive loads and general-purpose lighting circuits where inrush stays low. It is not intended for motor or transformer starting — those need Curve C or D to ride through the magnetizing inrush without nuisance tripping.
Panel integration — DIN rail fit
Snaps onto a standard 35 mm DIN rail per EN 60715. The 3-pole footprint occupies three modular units (17.5 mm per pole) on the rail. Terminal design accepts copper conductors up to 25 mm² — sized for the 6 A branch circuit it protects.