Locked Rotor Design Code Letters – Electrical Motors
NEMA code letters designate the classification of electrical motors by the ratio of locked rotor kVA per horsepower. Generally, smaller motors require a higher starting kVA than larger motors. The kVA required by a motor starting at full voltage can be determined from the manufacturer, or from the nameplate on the motor.
Locked Rotor Design Code Letters
| NEMA Code Letter | kVA/HP with Locked Rotor | Approximate Mid-Range Value |
| A | 0- 3.14 | 1.6 |
| B | 3.15 - 3.55 | 3.3 |
| C | 3.55 - 3.99 | 3.8 |
| D | 4.0 - 4.49 | 4.3 |
| E | 4.5 - 4.99 | 4.7 |
| F | 5.0 - 5.59 | 5.3 |
| G | 5.6 - 6.29 | 5.9 |
| H | 6.3 - 7.09 | 6.7 |
| J | 7.1 - 7.99 | 7.5 |
| K | 8.0 - 8.99 | 8.5 |
| L | 9.0 - 9.99 | 9.5 |
| M | 10.0 - 11.19 | 10.6 |
| N | 11.2 - 12.49 | 11.8 |
| P | 12.5 - 13.99 | 13.2 |
| R | 14.0 - 15.99 | 15.0 |
| S | 16.0 - 17.99 | |
| T | 18.0 - 19.99 | |
| U | 20.0 - 22.39 | |
| V | 22.4 - and up |
Standard 3-Phase Motor Locked Rotor Codes
L >> Less than 1 HP >> 9.0 - 9.99 kVA
L or M >> 1 1/2 - 2HP >> 9.0 - 11.19 kVA
K >> 3 HP >> 8.0 - 8.99 kVA
J >> 5HP >> 7.1 - 7.99 kVA
H >> 7.5 - 10 HP >> 6.3 - 7.09 kVA
G >> More than 15HP >> 5.6 - 6.29 kVA
For more assistance determining the wattage you need, use our Power Calculator, or contact a trained Absolute Generators specialist.
