The Schneider Electric A9S60491 is a 4-pole switch disconnector from the Acti9 iSW series, rated 100 A at 415 V AC 50/60 Hz. It is designed for control isolation duty under IEC 60947-3, with an AC-22A utilisation category — meaning it handles mixed resistive and inductive loads typical of distribution panels, not motor starting. The 6 kV impulse withstand voltage (Uimp) and pollution degree 3 rating suit it for industrial environments where transient overvoltages and conductive dust are present. Mounts on a DIN rail (fixed mode) and occupies 72 mm width (4 x 18 mm per pole). The toggle control gives a clear ON/OFF indication, and a contact position indicator confirms the isolation state — critical for lockout/tagout procedures.
The insulation voltage (Ui) is 500 V AC, so the switch is suitable for 400 V class systems with margin. Electrical durability is 10,000 cycles, mechanical durability 50,000 cycles. For a switch disconnector used mainly for isolation (infrequent operation), this is ample. The tropicalisation class 2 indicates the part is treated against humidity and fungal growth — relevant for installations in warm, damp climates.