In the United States, the National Electric Manufacturers Association (NEMA) establishes standard dimensions for electric motors. The rating plate of a motor will give a “frame size,” consisting of a number which may be followed by a letter. In purchasing a replacement motor, it is only necessary to get the same frame size to be sure of a physical fit (horsepower, voltage, type of enclosure, bearings, etc. are another matter). In the home, the most commonly encountered frame sizes are 48 and 56.
Size | D | 2E | 2F | BA | Mounting | NW | U |
---|---|---|---|---|---|---|---|
48 | 2⅝ | 4¼ | 2¾ | 2½ | 11/32 slot | 1½ | ½ |
56 | 3½ | 4⅞ | 3 | 2¾ | 11/32 slot | 1⅞ | ½ |
The NEMA standards also describe the way the motor shaft is modified so that pulleys and gears can be securely fastened to it.
Size | Key on shaft |
---|---|
48 | 29/64″ flat |
56 | 3/16″ wide, 3/16″ deep, 1 3/8″ long slot |
Description | |
---|---|
Bombardier/Alstom HHP-8 |
8,000 horsepower electric locomotive. |
Sorry. No information on contributors is available for this page.
Copyright © 2002 Sizes, Inc. All rights reserved.
Last revised: 3 June 2002.