Technical information

FEEDER AND BRANCH CIRCUITS

The suitable IEC/UL/CSA component is a 194R-NN060P3 (CCN,WJAZ,

conforming to UL 489) while in a NEMA start a 1494F-N60 (CCN,WHTY,

conforming to UL 98) is used, both with power rating equal to 15 hp (230V).

2.2 Sizing according to the CEC for the Canadian market

The sizing regulations are simplified because no distinction is made between

circuit breaker and switches and only the following rules are applied:

•size in current of the device should not be less than 115% of the current of the

largest motor plus the sum of all the FLAs of the other motors and all the rated

currents of the various loads from the motors.

•The power size of the device, if indicated should not be less than the power of

the largest motor.

2.3 Sizing in accordance with the NEC

The sizing of the switching device in the NEC requires the verification of two

different conditions, depending on the use of a power characterized component

(switch: hp rating) or characterized in current (circuit breaker: rating in A):

however some exceptions are applied. No other distinction is made between

circuit breaker and switches.

•Sizing in current: the size in current of the device should not be lower than

115% of the total current, obtained as the sum of the FLA of all the other loads.

•Sizing in power: two values are calculated, one relative to the sum of the FLAs

(current at full load, tab 430.250 of NEC or tab. 50.1 of UL 508A) and one to the

sum of the LRA (current with the rotor blocked table 430.251(B) of NEC) of all

the motors.The nominal currents of all the other loads (not motor) should be

Sect. (1.15x22) + 8 + 4 >=37.3A

Cond. 1.25 x 22 + 1.25 x 8 + 4 > = 41.5 A

AWG 8 (50A)