FAQ

Material taken from the National Electric Code

is reprinted with permission

from NFPA 70

, 2023 edition. National Electrical Code

NEC

Text

and the marking on the equipment nameplate is not less than the current

marked on the fan or blower motor nameplate, the full-load current marked

on the nameplate of the appliance shall be used to determine the ampacity of

branch-circuit conductors, in addition to the current ratings of the following:

(1) Disconnecting means

(2) Motor controllers

(3) Short-circuit and ground-fault protective devices

(4) Separate overload protective devices

Exception No. 3: For a listed motor-operated appliance that is marked with

both motor horsepower and full-load current, the motor full-load current

marked on the nameplate of the appliance shall be used instead of the

horsepower rating on the appliance nameplate to determine the ampacity of

branch-circuit conductors, in addition to the current ratings of the following:

(1) Disconnecting means

(2) Motor controllers

(3) Short-circuit and ground-fault protective devices

(4) Separate overload protective devices

(2) Nameplate Values. The motor nameplate current ratings

shall be used to determine the values for the following:

(1) Separate motor overload protection

(2) For motors built for low speeds (less than 1200 RPM),

high torques, canned pumps, or multispeed motors, the

following:

a. Ampacity of conductors

b. Current ratings of switches

c. Current ratings of branch-circuit short-circuit and ground-

fault protection

(3) Large motors exceeding the values in Part XIV shall use

the nameplate current rating for conductor sizing.

Expert Analysis

A revision has been made to clarify the requirements

when applying nameplate or table values for general

motor applications.

continued on page 84

Sizing Using Table