Electrician Practice Tests

Total connected load = 140 KVA

Refer : NEC Table 220.88

First 200 KVA load is at 80% so

Total demand load  140 * 0.8 = 112 KVA

ampacity I = VA / [E * 1.732 ] = (112 * 10³ )  / (208 * 1.732)

= 311 amperes

Refer : NEC 440.22 (A)

The branch circuit protection ratings should be 175% of motor current rating.

branch circuit rating = 20 * 1.75 = 35 amperes

Refer : NEC 210.23(B)

30 ampere branch circuit with heavy duty lamp holders is permitted to supply fixed lightening units other than dwelling unit .

Refer :  NEC Table 220.12

for dwelling unit minimum general lightening load is 3 VA / square foot

Total load = 1500 * 3 = 4500 VA

Refer : I = P / E

I  = 48000 / 240 = 200 amperes

Refer: NEC 220.56

For load calculation of a commercial kitchen with only one electric appliance should be rated at 100%. For applying deductions there must be at-least three or more appliances should be available.

If more than 3 conductors are placed in a conduit the conductor ampacity must be derated.

Refer: NEC Table 310.15(B)(3)

For 5 conductors in a conduit the de-rating factor is 80%

maximum allowable ampacity = 0.8 * 195 = 156 amperes

Refer : NEC 406.3 (D)

An orange triangle located on the face of the receptacle.

Refer : NEC 408.36 (A)

the maximum rating of Panel boards containing 30 amperes or less snap switches should be less than 200 amperes.