Side-by-side mounting is permitted, which keeps multi-contactor motor starter assemblies compact on the rail.
The AC-3 rating of 18.5 kW at 500 V governs the motor load this contactor can switch — that is the standard duty for squirrel-cage motors during starting and running, so it covers pumps, fans, and conveyors up to that power. At 400 V AC-3 the rating is 15 kW. For resistive loads (AC-1) the mechanical endurance is 1 200 operations per hour maximum; for AC-3 it is 1 000 operations per hour, and for the most severe AC-4 plugging/reversing duty it drops to 250 operations per hour. The coil holds at 24 VDC; the DC arcing time is 20 to 30 ms, and the overall arcing time is 10 to 15 ms.
The screw-type terminals accept solid conductors 2x (0.25 to 2.5 mm²) and stranded conductors 2x (0.75 to 25 mm²). For the main circuit, the solid or stranded range is 2x (0.75 to 16 mm²). At 40 °C the minimum permissible cross-section is 16 mm². These ranges cover standard panel wiring from control-circuit signal wires up to motor feeder cables.