How to Read Electric Motor Nameplate Data

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The nameplate of a motor provides important information necessary for proper ordering, replacement and application. To help in the proper application of electric motors, the National Electrical Manufacturers Association (NEMA) and other bodies like the IEC (International Electrotechnical commission) define some basic design, performance and mounting parameters to aid in standardizing electric motors. These parameters are then coded onto the motor nameplate to give a basic definition of what you have received.
Motor nameplate data can be categorized according to the following parameters:

(a) General Data
(b) Electrical input
(c) Mechanical output
(d) Motor Design
(e) Performance
(f) Safety
(g) Reliability
(h) Construction

Nameplate data is the critical first step in determining motor replacement.  It is a treasury of important information about a motor. If you specify, buy, maintain, or replace motors, you should know how to read them by going through this post.
The following parameters are the minimum information that can be found on the nameplates of single and poly-phase induction motors:

General Data
A typical nameplate also include general information such as the motor's brand name, a "Serial No." or other identifying number unique to that motor, that would let the manufacturer trace the motor back through manufacturing. The nameplate also includes the manufacturer's name, and its principal city and state and "Made in U.k." if U.k -made.