Skip to content

How to find the right motor


There are two ways to determine a suitable motor replacement:

  1. Cross Referencing the Motor Manufacturer's part number

The most accurate method to find a replacement motor is to cross-reference the manufacturer's part number or model number from the motor itself. This number is usually found on the nameplate (label) of the motor along with the other nameplate data, such as horsepower, volts, etc.

 

Click picture to enlarge

 Note: A motor nameplate sometimes has several different identifying numbers, which can be confusing. Keep in mind that some motors are made for other companies who then put their part number on the motor. The key is to locate the motor manufacturer's part number.

If you can't find what you're looking for and would like us to help, please use the form at the bottom of this page. We'll email you the information you're looking for as soon as possible. Or of course you can always call us at 800-270-4579.

 

  1. Matching the Motor Specifications

If cross-referencing doesn't work, another option is trying to match the electrical specifications and physical dimensions of the defective motor itself. It's important to provide as much information as possible since the slightest difference in shaft size, mounting, or electrical specs can mean the difference between success and failure in a motor replacement.

The motor specifications include the following:

Electrical Specs: (these can usually be found on the motor’s nameplate)

  • HP
  • Volts
  • Amps
  • RPMs
  • Service Factor/SF (if applicable)
  • Number of Speeds
  • Rotation (CW, CCW, or Reversible) Note: For single shaft motors, view rotation from the shaft end; for double-shaft motors, view rotation from the lead end (i.e. the end where the wires come out)
  • Phase (1 or 3) Note: Industrial applications often use 3-Phase power.

 

Physical Dimensions:

  • Frame Size (if provided; if not, then continue below)
  • Length and Diameter of Motor
  • Length and Diameter of Shaft
  • Number of Shafts (1 or 2)

 

Mounting:

  • What is the mounting style of the motor? (rigid base, belly band, thru-bolts, cradle [resilient] base, etc.)
  • Vertical or Horizontal. If vertical, is the shaft up or down?

 

Enclosure:

  • Is the motor open drip-proof (ODP), totally enclosed air over (TEAO), totally enclosed fan cooled (TEFC), etc. Basically, how is it enclosed/protected?
  • Does it require any special protection (i.e. hazardous location, washdown duty, etc).

 

Additional Specs:

  • Ball or sleeve bearing?
  • Motor type (shaded pole, permanent split capacitor (PSC), capacitor start, etc.)
  • Motor application (what application is the motor used in? i.e. a furnace blower, vent fan, pool pump, air compressor, etc.)