A 150 kVA, single-phase transformer having a secondary voltage of one hundred twenty/240 is
to be hooked up at a multi-own family living. The modern-day to be had on the secondary is
_____ amperes.
A) 329
b) 421
c) 625
d) 729 - ANS-C: 625
Sol:
I = P/E
I = 150,000 va / 240 volts
I = 625 amperes
A receptacle outlet installed for a gasoline or electric garments dryer in the laundry room of a
residing unit need to be established within at LEAST _____ toes of the intended place of the
dryer.
A) 6
b) four
c) 10
d) three - ANS-A: 6
Ref: 210.50(C)
All 125-volt, unmarried-section, 15- and 20-ampere receptacles hooked up in residential
garages shall be _____.
I) covered by a listed arc-fault interrupter
II) provided with ground-fault circuit-interrupter protection
a) I handiest
b) II only
c) each I and II
d) neither I nor II - ANS-B: II simplest
Ref: 210.8(A)(2); 210.12(B)
Electrical outlet packing containers mounted in partitions and ceilings are required to be _____.
A) visible
b) quite simply accessible
c) available
d) steel - ANS-C: available
Ref: 314.29
Ferrous steel enclosures for grounding electrode conductors will be _____.
A) electrically continuous
, b) electrically isolated
c) now not authorised
d) inflexible metal conduit (RMC) only - ANS-A: electrically continuous
Ref: 250.64(E)
Given: a one hundred twenty-volt lighting branch-circuit is to deliver best six a hundred watt, one
hundred twenty-volt, incandescent luminaires. Determine the full cutting-edge on this
branch-circuit.
A) 30 amperes
b) 20 amperes
c) five amperes
d) 12 amperes - ANS-C: five amperes
Sol:
a hundred x 6 = 600 watts overall
I = P/E
I = 600 watts / a hundred and twenty volts
I = five amperes
Given: a 40-gallon electric powered water heater has a nameplate rating of 4,500 watts at 240
volts. What is the MAXIMUM fashionable length circuit breaker the NEC permits to shield the
water heater?
A) 20 amperes
b) 25 amperes
c) 30 amperes
d) forty five amperes - ANS-C: 30 amperes
Ref: 422.Eleven(E)(3); 240.6(A); Current Formula
Sol:
I = P/E
I = 4500 va / 240 volts
I = 18.Seventy five amps x a hundred and fifty percentage
I = 28.1 amperes
Given: you're to put in a 20-ampere, 120-volt, GFCI included, buried, UF cable
department-circuit that resources landscape lights for a house. The UF cable is required to have
a ground cowl of at LEAST _____.
A) 6 inches
b) 12 inches
c) 18 inches
d) 24 inches - ANS-B: 12 inches
Ref: Tbl. Three hundred.5, Col. 4
If a cable or raceway enters an enclosure which include a meter base, above uninsulated live
components in a moist place, the fittings used to connect the enclosure have to be _____ for
wet locations.