The 187 kA interrupting rating at 240 V is the figure that governs fault-current compliance on a 480Y/277 V secondary — the 121 kA at 415/440 V still covers most industrial low-voltage switchgear applications. At 690 V the 3 kA rating is a residual capability for special installations, not the primary duty. Power loss is 7.9 W maximum — low enough to gang multiple breakers without forced ventilation.
Built-in accessories and wiring
The UVR means the breaker drops out on loss of control voltage — a standard safety interlock for emergency-stop circuits and undervoltage protection schemes. The base switch assembly is order code 3VA20635HL320AA0; if you ever need to replace the switching mechanism alone, that is the spare part number to order.