Whenever someone brings up IEC contactors IEC contactors/starters are more appication specifc. NEMA contacts often times an overkill. When an IEC device is properly applied they are less expensive as well as smaller.
IEC ratings for contactors are sized based on application and motor ratings. For AC motors there are four utilization categories:
AC1- Resistive loads such as heaters with a power factor greater than .95
AC2- Starting, plugging, inching and jogging of slip ring motors.
AC3- Line starting and breaking during normal running of standard squirrel cage inductive motors. Application examples include lifts, conveyers, pumps, fans etc. This is considered ?normal? duty for AC motors.
AC4- Plugging, inching and jogging of squirrel cage and slip ring motors. Application examples include cranes, hoists, printing machines, etc.
IEC contactors are sized precisely based on one of the AC utilization ratings noted above. Normal duty or the AC3 rating is typically used for sizing the contactor. For example a 32 amp IEC contactor like our CRC 32 is rated for 32 amps full load current at 220 to 460VAC in AC3 applications. To size the contactor properly you will need to know the voltage, current and HP and use the appropriate 'AC' rating.