NEC Table 430.247 — Direct-Current Motors Full-Load Current

DC motors running at base speed; voltages are armature voltage ratings.

A 5 HP DC motor draws 20 A at 240 V, and a 125 HP motor draws 185 A at 550 V. Use these values, not the nameplate, to size conductors and short-circuit protection.

Full-load current in amps — direct-current motors
Horsepower90 V120 V180 V240 V500 V550 V
1/4 HP43.121.6
1/3 HP5.24.12.62
1/2 HP6.85.43.42.7
3/4 HP9.67.64.83.8
1 HP12.29.56.14.7
1 1/2 HP13.28.36.6
2 HP1710.88.5
3 HP251612.2
5 HP402720
7 1/2 HP582913.612.2
10 HP76381816
15 HP552724
20 HP723431
25 HP894338
30 HP1065146
40 HP1406761
50 HP1738375
60 HP2069990
75 HP255123111
100 HP341164148
125 HP425205185
150 HP506246222
200 HP675330294

Frequently asked questions

How many amps does a 5 HP direct-current motor draw?

A 5 HP DC motor draws 20 A at 240 V. 40 A at 120 V, 27 A at 180 V, 20 A at 240 V.

Should I use the nameplate amps or the table amps?

Use the table full-load current for sizing branch-circuit conductors, the short-circuit and ground-fault protective device, and the disconnect (430.6(A)(1)). Use the motor nameplate current only for sizing the separate overload protection.

NECTables.com is an independent reference and is not affiliated with, endorsed by, or a substitute for the National Fire Protection Association (NFPA). NEC® and National Electrical Code® are registered trademarks of the NFPA. Values shown are commonly published engineering data and independent calculations based on the methods of NFPA 70; they are not a reproduction of the Code. Always confirm against the edition adopted in your jurisdiction, including local amendments, and consult a licensed electrician or engineer before doing electrical work.