CBS-NEMA Electric Motor Frame Chart
This Site Is Provided As A Service Of
Clarksville Bearing & Supply, Inc.
Call Toll Free 888-414-3933 Fax 479-754-9721
NEMA
frame guide
| The National Electrical Manufacturers Association (NEMA) has
established industry-standard, base-mounted motor dimensions, which we have listed below. What this means, is that all motors manufactured under NEMA specifications, will have the same dimensions, regardless of who manufactured the motor. So, if a motor is a 143T frame, then all motors with a 143T frame will have the dimensions. NOTE: any frame designation followed by either a "Z" or "Y" or "YZ" means that the motor has been changed and no longer follows these rules. The shaft may be different, ie, longer, shorter, diameter, threaded, ect. And as a result is no longer a "standard" motor. |
|
All Dimensions in
inches
|
NEMA |
D* |
2E |
2F |
BA |
H |
N Min. | U shaft |
V |
Key |
Key |
Key |
| 42 | 2 5/8 | 3 1/2 | 1 11/16 | 2 1/16 | 9/32 slot | 1 1/8 | 3/8 | _ | _ | 3/64 flat | _ |
| 48 | 3 | 4 1/4 | 2 3/4 | 2 1/2 | 11/32 slot | 1 1/2 | 1/2 | _ | _ | 3/64 flat | _ |
| 48H | 3 | 4 1/4 | 4 3/4 | 2 1/2 | 11/32 slot | 1 1/2 | 1/2 | _ | _ | 3/64 flat | _ |
| 56 | 3 1/2 | 4 7/8 | 3 | 2 3/4 | 11/32 slot | 1 7/8 @ |
5/8 @ | _ | 3/16 @ | 3/16 @ | 1 3/8 @ |
| 56H | 3 1/2 | 4 7/8 | 3&5@@ | 2 3/4 | 11/32 slot | 1 7/8 @ |
5/8 @ | _ | 3/16 @ | 3/16 @ | 1 3/8 @ |
| 56HZ | 3 1/2 | ** | ** | ** | ** | 2 1/4 | 7/8 | 2 | 3/16 @ | 3/16 @ | 1 3/8 @ |
| 66 | 4 1/8 | 5 7/8 | 5 | 3 1/8 | 13/32 slot | 2 1/4 | 3/4 | _ | 3/16 | 3/16 | 1 7/8 |
| 143T | 3 1/2 | 5 1/2 | 4 | 2 1/4 | 11/32 | 2 1/4 | 7/8 | 2 | 3/16 | 3/16 | 1 3/8 |
| 145T | 3 1/2 | 5 1/2 | 5 | 2 1/4 | 11/32 | 2 1/4 | 7/8 | 2 | 3/16 | 3/16 | 1 3/8 |
| 146AT | 3 1/2 | 5 1/2 | 5 1/2 | 2 3/4 | 11/32 | 2 1/4 | 7/8 | 2 | 3/16 | 3/16 | 1 3/8 |
| 148AT | 3 1/2 | 5 1/2 | 7 | 2 3/4 | 11/32 | 2 1/4 | 7/8 | 2 | 3/16 | 3/16 | 1 3/8 |
| 149AT | 3 1/2 | 5 1/2 | 8 | 2 3/4 | 11/32 | 2 1/4 | 7/8 | 2 | 3/16 | 3/16 | 1 3/8 |
| 1412AT | 3 1/2 | 5 1/2 | 11 | 2 3/4 | 11/32 | 2 1/4 | 7/8 | 2 | 3/16 | 3/16 | 1 3/8 |
| 182 | 4 1/2 | 7 1/2 | 4 1/2 | 2 3/4 | 13/32 | 2 1/4 | 7/8 | 2 | 3/16 | 3/16 | 1 3/8 |
| 184 | 4 1/2 | 7 1/2 | 5 1/2 | 2 3/4 | 13/32 | 2 1/4 | 7/8 | 2 | 3/16 | 3/16 | 1 3/8 |
| 182T | 4 1/2 | 7 1/2 | 4 1/2 | 2 3/4 | 13/32 | 2 3/4 | 1 1/8 | 2 1/2 | 1/4 | 1/4 | 1 3/4 |
| 184T | 4 1/2 | 7 1/2 | 5 1/2 | 2 3/4 | 13/32 | 2 3/4 | 1 1/8 | 2 1/2 | 1/4 | 1/4 | 1 3/4 |
| 182AT | 4 1/2 | 7 1/2 | 4 1/2 | 2 3/4 | 13/32 | 2 1/4 | 1 1/8 | 2 | 1/4 | 1/4 | 1 3/8 |
| L182ACY | 4 1/2 | 7 1/2 | 4 1/2 | 2 3/4 | 13/32 | 2 1/4 | 7/8 | 2 | 3/16 | 3/16 | 1 3/8 |
| 182AT | 4 1/2 | 7 1/2 | 4 1/2 | 2 3/4 | 13/32 | 2 1/4 | 1 1/8 | 2 | 1/4 | 1/4 | 1 3/8 |
| 186ACY | 4 1/2 | 7 1/2 | 7 | 2 3/4 | 13/32 | 2 1/4 | 7/8 | 2 | 3/16 | 3/16 | 1 3/8 |
| 186AT | 4 1/2 | 7 1/2 | 7 | 2 3/4 | 13/32 | 2 1/4 | 1 1/8 | 2 | 1/4 | 1/4 | 1 3/8 |
| L186AT | 4 1/2 | 7 1/2 | 7 | 2 3/4 | 13/32 | 2 1/4 | 1 1/8 | 2 | 1/4 | 1/4 | 1 3/8 |
|
NEMA |
D* |
2E |
2F |
BA |
H |
N Min. |
U |
V |
Key |
Key |
Key |
| 189AT | 4 1/2 | 7 1/2 | 10 | 2 3/4 | 13/32 | 2 1/4 | 1 1/8 | 2 | 1/4 | 1/4 | 1 3/8 |
| 203# | 5 | 8 | 5 1/2 | 3 1/8 | 13/32 | 2 1/4 | 3/4 | 2 | 3/16 | 3/16 | 1 3/8 |
| 204# | 5 | 8 | 6 1/2 | 3 1/8 | 13/32 | 2 1/4 | 3/4 | 2 | 3/16 | 3/16 | 1 3/8 |
| 213 | 5 1/4 | 8 1/2 | 5 1/2 | 3 1/2 | 13/32 | 3 | 1 1/8 | 2 3/4 | 1/4 | 1/4 | 2 |
| 215 | 5 1/4 | 8 1/2 | 7 | 3 1/2 | 13/32 | 3 | 1 1/8 | 2 3/4 | 1/4 | 1/4 | 2 |
| 213T | 5 1/4 | 8 1/2 | 5 1/2 | 3 1/2 | 13/32 | 3 | 1 3/8 | 3 1/8 | 5/16 | 5/16 | 2 3/8 |
| 215T | 5 1/4 | 8 1/2 | 7 | 3 1/2 | 13/32 | 3 3/8 | 1 3/8 | 3 1/8 | 5/16 | 5/16 | 2 3/8 |
| 219AT | 5 1/4 | 8 1/2 | 11 | 3 1/2 | 13/32 | 2 3/4 | 1 3/8 | 2 1/2 | 5/16 | 5/16 | 1 3/4 |
| 2110AT | 5 1/4 | 8 1/2 | 12 1/2 | 3 1/2 | 13/32 | 2 3/4 | 1 3/8 | 2 1/2 | 5/16 | 5/16 | 1 3/4 |
| 224 # | 5 1/2 | 9 | 6 3/4 | 3 1/2 | 13/32 | 3 | 1 | 2 3/4 | 1/4 | 1/4 | 2 |
| 225 # | 5 1/2 | 9 | 7 1/2 | 3 1/2 | 13/32 | 3 | 1 | 2 3/4 | 1/4 | 1/4 | 2 |
| 254# | 6 1/4 | 10 | 8 1/4 | 4 1/4 | 21/32 | 3 3/8 | 1 1/8 | 3 1/8 | 1/4 | 1/4 | 2 3/8 |
| 254U | 6 1/4 | 10 | 8 1/4 | 4 1/4 | 17/32 | 3 3/4 | 1 3/8 | 3 1/2 | 5/16 | 5/16 | 2 3/4 |
| 256U | 6 1/4 | 10 | 10 | 4 1/4 | 17/32 | 3 3/4 | 1 3/8 | 3 1/2 | 5/16 | 5/16 | 2 3/4 |
| 254T | 6 1/4 | 10 | 8 1/4 | 4 1/4 | 17/32 | 4 | 1 5/8 | 3 3/4 | 3/8 | 3/8 | 2 7/8 |
| 256T | 6 1/4 | 10 | 10 | 4 1/4 | 17/32 | 4 | 1 5/8 | 3 3/4 | 3/8 | 3/8 | 2 7/8 |
| 284 # | 7 | 11 | 9 1/2 | 4 3/4 | 21/32 | 3 3/4 | 1 1/4 | 3 1/2 | 1/4 | 1/4 | 2 3/4 |
| 284U | 7 | 11 | 9 1/2 | 4 3/4 | 17/32 | 4 7/8 | 1 5/8 | 4 5/8 | 3/8 | 3/8 | 3 3/4 |
| 286U | 7 | 11 | 11 | 4 3/4 | 17/32 | 4 7/8 | 1 5/8 | 4 5/8 | 3/8 | 3/8 | 3 3/4 |
| 284T | 7 | 11 | 9 1/2 | 4 3/4 | 17/32 | 4 5/8 | 1 7/8 | 4 3/8 | 1/2 | 1/2 | 3 1/4 |
| 286T | 7 | 11 | 11 | 4 3/4 | 17/32 | 4 5/8 | 1 7/8 | 4 3/8 | 1/2 | 1/2 | 3 1/4 |
| 284TS | 7 | 11 | 9 1/2 | 4 3/4 | 17/32 | 3 1/4 | 1 5/8 | 3 | 3/8 | 3/8 | 1 7/8 |
| 286TS | 7 | 11 | 11 | 4 3/4 | 17/32 | 3 1/4 | 1 5/8 | 3 | 3/8 | 3/8 | 1 7/8 |
| 324 # | 8 | 12 1/2 | 10 1/2 | 5 1/4 | 21/32 | 4 7/8 | 1 5/8 | 4 5/8 | 3/8 | 3/8 | 3 3/4 |
| 326 # | 8 | 12 1/2 | 10 1/2 | 5 1/4 | 21/32 | 4 7/8 | 1 5/8 | 4 5/8 | 3/8 | 3/8 | 3 3/4 |
| 324U | 8 | 12 1/2 | 10 1/2 | 5 1/4 | 21/32 | 5 5/8 | 1 7/8 | 5 3/8 | 1/2 | 1/2 | 4 1/4 |
| 326U | 8 | 12 1/2 | 12 | 5 1/4 | 21/32 | 5 5/8 | 1 7/8 | 5 3/8 | 1/2 | 1/2 | 4 1/4 |
| 324T | 8 | 12 1/2 | 10 1/2 | 5 1/4 | 21/32 | 5 1/4 | 2 1/8 | 5 | 1/2 | 1/2 | 3 7/8 |
| 326T | 8 | 12 1/2 | 12 | 5 1/4 | 21/32 | 5 1/4 | 2 1/8 | 5 | 1/2 | 1/2 | 3 7/8 |
| 324TS | 8 | 12 1/2 | 10 1/2 | 5 1/4 | 21/32 | 3 3/4$ | 1 7/8$ | 3 1/2$ | 1/2 | 1/2 | 2 $ |
| 326TS | 8 | 12 1/2 | 12 | 5 1/4 | 21/32 | 3 3/4$ | 1 7/8$ | 3 1/2$ | 1/2 | 1/2 | 2 $ |
| 364 # | 9 | 14 | 11 1/4 | 5 7/8 | 21/32 | 5 5/8 | 1 7/8 | 5 3/8 | 1/2 | 1/2 | 4 1/4 |
| 364S # | 9 | 14 | 11 1/4 | 5 7/8 | 21/32 | 3 1/4 | 1 5/8 | 3 | 3/8 | 3/8 | 1 7/8 |
| 365 # | 9 | 14 | 12 1/4 | 5 7/8 | 21/32 | 5 5/8 | 1 7/8 | 5 3/8 | 1/2 | 1/2 | 4 1/4 |
| 364U | 9 | 14 | 11 1/4 | 5 7/8 | 21/32 | 6 3/8 | 2 1/8 | 6 1/8 | 1/2 | 1/2 | 5 |
| 365U | 9 | 14 | 12 1/4 | 5 7/8 | 21/32 | 6 3/8 | 2 1/8 | 6 1/8 | 1/2 | 1/2 | 5 |
| 364T | 9 | 14 | 11 1/4 | 5 7/8 | 21/32 | 5 7/8 | 2 3/8 | 5 7/8 | 5/8 | 5/8 | 4 1/4 |
| 365T | 9 | 14 | 12 1/4 | 5 7/8 | 21/32 | 5 7/8 | 2 3/8 | 5 7/8 | 5/8 | 5/8 | 4 1/4 |
| 364TS | 9 | 14 | 11 1/4 | 5 7/8 | 21/32 | 3 3/4$ | 1 7/8 | 3 1/2$ | 1/2 | 1/2 | 2 $ |
| 365TS | 9 | 14 | 12 1/4 | 5 5/8 | 21/32 | 3 3/4$ | 1 7/8 | 3 1/2$ | 1/2 | 1/2 | 2 $ |
| 404T | 10 | 16 | 12 1/4 | 6 5/8 | 13/16 | 7 1/4 | 2 7/8 | 7 | 3/4 | 3/4 | 5 5/8 |
| 405T | 10 | 16 | 13 3/4 | 6 5/8 | 13/16 | 7 1/4 | 2 7/8 | 7 | 3/4 | 3/4 | 5 5/8 |
| 404TS | 10 | 16 | 12 1/4 | 6 5/8 | 13/16 | 4 1/4$ | 2 1/8$ | 4 $ | 1/2 | 1/2 | 2 3/4$ |
| 405TS | 10 | 16 | 13 3/4 | 6 5/8 | 13/16 | 4 1/4$ | 2 1/8$ | 4 $ | 1/2 | 1/2 | 2 3/4$ |
| 404U | 10 | 16 | 12 1/4 | 6 5/8 | 13/16 | 7 1/8 | 2 3/8 | 6 7/8 | 5/8 | 5/8 | 5 1/2 |
| 405U | 10 | 16 | 13 3/4 | 6 5/8 | 13/16 | 7 1/8 | 2 3/8 | 6 7/8 | 5/8 | 5/8 | 5 1/2 |
| 444T | 11 | 18 | 14 1/2 | 7 1/2 | 13/16 | 8 1/2 | 3 3/8 | 8 1/4 | 7/8 | 7/8 | 6 7/8 |
| 445T, 447T && |
11 | 18 | 16 1/2 | 7 1/2 | 13/16 | 8 1/2 | 3 3/8 | 8 1/4 | 7/8 | 7/8 | 6 7/8 |
| 444TS, 447TS&& |
11 | 18 | 14 1/2 | 7 1/2 | 13/16 | 4 3/4$ | 2 3/8$ | 4 1/2$ | 5/8 | 5/8 | 3 $ |
| 445TS | 11 | 18 | 16 1/2 | 7 1/2 | 13/16 | 4 3/4$ | 2 3/8$ | 4 1/2$ | 5/8 | 5/8 | 3 $ |
| 444U | 11 | 18 | 14 1/2 | 7 1/2 | 13/16 | 8 5/8 | 2 7/8 | 8 3/8 | 3/4 | 3/4 | 7 |
| 445U | 11 | 18 | 16 1/2 | 7 1/2 | 13/16 | 8 5/8 | 2 7/8 | 8 3/8 | 3/4 | 3/4 | 7 |
| 449T | 11 | 18 | 25 | 7 1/2 | 13/16 | 8 1/2 | 3 3/8 | 8 1/4 | 7/8 | 7/8 | 6 7/8 |
| 449TS | 11 | 18 | 25 | 7 1/2 | 13/16 | 4 3/4$ | 2 3/8$ | 4 1/2$ | 5/8 | 5/8 | 3 $ |
* Dimension D Will never be greater than the above values on rigid mount motors, but it may be less so that shims up to 1/32" thick (1/16" on 364U and 365U frames) may be required for certain machines.
@@Motors designated 56H have two sets of 2F mounting holes--3" and 5".
$ Standard short shaft for direct drive applications.
# Discontinued "pre-NEMA" frame.
**Base of 56HZ frame motors has holes and slots to match NEMA 56,56H,143T & 145T mounting dimensions.
& Dimension "V" is shaft length available for coupling, pinion or pulley hub--this is a minimum value.