Calculations for Motors Flashcards
Article for locked rotor current
430.251
Article for overload selection
430.32
Overloads are sized from the ___
FLA of the motor
Table for OCPD’s
430.52
When sizing the OCPD for a branch ckt, if the size doesn’t correspond to a standard size, it is permissible to size the OCPD ___
Up
When sizing the OCPD for a feeder ckt, if the size doesn’t correspond to a standard size, it is permissible to size OCPD ___
Down
Branch wiring for a motor is sized by ___
125% of the motor FLC
Feeder wiring for multiple motors is sized by ___
125% of the FLC of the largest motor, plus the FLC of all other motors
OCPD for feeders is sized by ___
The largest branch OCPD, plus the FLC of all other motors
Standard disconnect sizes
30, 60, 100, 200, 400, 600, 800, 1200
Table for motor duty cycle
430.22(E)
Motor overloads are sized from the ___ of the motor
FLA
When a fuse is used as the overload protection for a motor, if the calculated requirement doesn’t correspond with an actual size, the fuse selected must be a size ___
Down
A fused disconnect for a motor shall have a rating not less than ___% of the FLC of the motor
115
The demand factors for welders are located in Table
630.11(A)
