The S801UE-K20 is a 2-pole miniature circuit breaker from ABB's S800 series, rated 6 A with a Trip Curve B characteristic. It mounts on a standard DIN rail and provides branch-circuit overcurrent protection for resistive and light inductive loads — think lighting panels, heater banks, and control transformers where the inrush stays under 3–5× rated current.
What the ratings mean for fit
The 6 A rating sets the continuous current the breaker carries without tripping. Trip Curve B means the magnetic trip fires at 3–5× In (18–30 A) — fast enough to clear a hard short but forgiving of the mild inrush from resistive loads. For motor circuits or transformer primaries with higher inrush, a Curve C or K breaker would be the better call; Curve B is for circuits where you want nuisance-tripping protection against small overloads. Two poles let it switch both line and neutral on a 277 VAC single-phase circuit, or both legs of a 110 VDC supply. The 6 kA interrupting rating means it can safely clear a fault up to 6,000 A at 277 VAC — adequate for most commercial-distribution panels downstream of a larger feeder breaker.
Panel integration
Snaps onto a standard 35 mm DIN rail. Two-pole width is 36 mm — two module spaces. Wire termination is via tunnel terminals; strip length and torque follow the ABB S800 series installation guide. No auxiliary contact slot on this base unit, but the S800 range accepts plug-in accessories for alarm or shunt-trip if the application needs remote signaling.