Sizing and fit for the branch circuit
The ABB S202MUC-C16 is a 2-pole miniature circuit breaker from the S200MUC series, rated at 1.6 A with a Trip Curve C characteristic. This means it's sized for a low-current branch — think control transformer primary, small power supply feed, or a lighting circuit with moderate inrush.
Rated 277 VAC and 500 VDC, so it covers single-phase line-to-neutral feeds in 277/480 V distribution and DC branch circuits up to 500 V. In a 277 VAC panel, the 6 kA rating is typical for downstream subpanels with limited available fault current; check your SCCR study to confirm it has headroom.