S801S-K20 — ABB S800S 1P K-Curve 20 A MCB
The ABB S801S-K20 is a 1-pole miniature circuit breaker from the S800S series, rated 20 A with a Trip Curve K characteristic. It mounts on a DIN rail and is rated for 230 VAC circuits. The 50 kA interrupting rating at 230 VAC means it can safely clear a fault up to that level without upstream damage — a key spec for high-fault-capacity panels where selectivity and SCCR headroom matter.
Trip Curve K — what it means for the buyer
Trip Curve K is a magnetic-only characteristic that sits between B and C curves on instantaneous trip threshold. It typically trips at 8–12× rated current (here, 160–240 A magnetic release). This makes it suited for circuits with moderate inrush — motor starters, transformer primaries, or inductive loads where a B curve would nuisance-trip but a D curve would be too slow. For a 20 A K-curve breaker, the thermal element handles overloads (1.13–1.45× In per IEC 60898), while the magnetic element clears short-circuits fast enough to protect downstream wiring.