Eaton Logo

Selecting a contactor or motor starter

Eaton sells a variety of contactors and starters; we need some more information in order to help you select one.

First - what type of contactor or starter do you need? This is application dependent. If you know which one you want, scroll down to the link that corresponds to the type - if you aren't sure here's the options:  

NEMA: Historically the North American market used NEMA rated contactors and starters. NEMA develops design standards and test specifications for device qualification.  They are considered very robust and have a very long electrical life.   These have a higher price point.  But if you are installing them into a more severe duty, industrial application that you want the product to last for decades, NEMA is the way the go. Steel mills, pulp & paper, petro-chem, rock crusher applications, etc. tend to use NEMA rated devices.  NEMA contactors and starters are not din rail mounted.  If you are looking for an enclosed starter, NEMA is the most readily available in a box.

IEC - This is an international standard that has been seeing increased usage in the U.S due to its cost effectiveness.  IEC contactors and starters are generally smaller/more compact than NEMA devices. They can be used in any application type but will not have the electrical life expectancy that NEMA rated devices will have, unless you use published utilization curves to achieve your desired electrical life.  Commonly used in material handling, car wash, packaging and OEM control panels.  IEC contactors and starters can be mounted on a din rail (up to 65amps) or panel mounted.

Definite Purpose (DP) - Definite purpose contactors and starters are intended to be used in the HVAC markets where low cost is the top priority, and the duty cycle is low.  These contactors are not designed to be turned on and off several times a minute.  They have a lower electrical life than both NEMA and IEC contactors.  

Once you have determined which type, you will need to know -

  • Is the motor non-reversing or reversing?
  • Load/motor Voltage, 
  • Control Voltage (ac/dc), also known as coil voltage.
  • Load Current (full load amps) ( or motor horsepower).  
  • Is the application three phase, single phase or DC?
  • Do you want the device open or enclosed (i.e., in a box  - if yes, what is the enlcosure type/ rating such as NEMA 1, NEMA 3R, NEMA 4X)?

For part# selection of NEMA open starters, click here:

How do I select a Freedom NEMA open contactor or starter?

For part# selection of NEMA enclosed starters, click here:

How do I select an enclosed Freedom NEMA starter?

For part# selection of open IEC contactors and starters click here:

How do I select an IEC contactor or motor starter?

For part# selection of Definite Purpose contactors and starters click here:

How do I select a definite purpose or DP contactor or starter?

Eaton Logo