What the ratings mean for fit
The S201-C25NA: The C-curve (5–10× In) means it's sized for moderate inrush loads — think small motors, transformers, or lighting banks in a control cabinet. The 480Y/277 V rating covers common North American 277/480 V wye distribution panels, so it slots into a lighting panel or a branch circuit feeding a VFD. The 1P+N configuration switches the line and monitors neutral, which is standard for single-phase branch circuits in a three-phase panel.
Panel integration
Snap-on DIN rail mount, 1 module wide (17.5 mm). The C-curve and 25 A rating mean it's a common choice for a lighting or general-purpose branch circuit in a 277/480 V panelboard. No special derating for side-by-side mounting at 25 A in a 30 °C ambient, but check the thermal derating curve above 40 °C if the panel runs hot.