Electrical-Level 3, Chapter 1
What is the decimal equivalent of square root of 3?
1.732
The general lighting load (expressed as a unit load per square foot) for a warehouse is _____.
1/4VA/sq ft
What is the current-carrying ampacity for each of 10 No. 10 THHN copper conductors installed in a single conduit?
20A
What is the minimum conductor ampacity for four 1,000W, 208V, 1Ø electric baseboard heaters?
24.04A
Branch circuit conductors supplying continuous duty loads are calculated at _____.
25% of the rated load
A continuous load is defined by the NEC® as a load whose maximum current is expected to continue for at least _____.
3 hours
What is the total load for two small appliance branch circuits rated at 20A, 120V?
3,000VA
The voltage drop for a 208V, 1Ø circuit with a load of 26.5A, using No. 8 stranded copper conductors at a circuit length of 145
5.98V
The voltage drop for a 208V, 1Ø circuit with a load of 26.5A, using No. 8 stranded copper conductors at a circuit length of 145 is _____.
5.98V
What is the recommended maximum voltage drop in a three-phase branch circuit with a voltage supply of 208V?
6.24V
How many receptacles are required for 90 linear feet of show window area?
8
What is the demand load for one range with a nameplate rating of 10.8kW?
8kW
Which size copper branch circuit conductors are required to supply an air conditioning unit with a nameplate rating of 33.5A, 208V, 3Ø?
No. 6
The load for 6 of multi-outlet assembly used simultaneously is _____.
1,080VA
What is the capacity, in amperes, for a 20A circuit breaker supplying a continuous load?
16A
What is the calculated load on a 120V branch circuit that is to supply twenty 60W incandescent fixtures?
10A
What is the calculated load, in amps, for a 120V circuit supplying four 150W recessed incandescent fixtures and six recessed fluorescent fixtures operating continuously? (Each fluorescent ballast is rated at 0.65A.)
11.125A
This question requires you to refer to the tables located in NEC Article 430. What is the motor full load current (FLA) for a 2hp, 230V, single-phase motor?
12A
How many receptacle outlets in a dentist's office can be connected to a 20A, single-phase 120V circuit if all of the outlets will supply noncontinuous loads? (Note: NEC Section 220.14(I) assigns a load of 180VA to each nonresidential outlet.)
13
What is the maximum number of general-purpose noncontinuous duty duplex receptacles that can be connected to a 20A, 120V circuit in a commercial building? What is the NEC® required load rating for each receptacle?
13 receptacles; 180VA
What is the maximum number of general-purpose noncontinuous duty duplex receptacles that can be connected to a 20A, 120V circuit in a commercial building? What is the NEC® required load rating for each receptacle? At a minimum, a 60' long show window would need _____ receptacles.
13 receptacles; 180VA
Using the resistance formula, the voltage drop for an 18A, 208V, 3Ø load with a total circuit length of 105 using No. 10 solid copper conductors is _____.
3.96V
The general lighting load for a store is _____.
3VA/sq ft
A continuous load has a maximum current of 25A. What is the minimum rating of the branch circuit that can be installed?
40A
What is the demand load, in amps, for one household electric range with a nameplate rating of 16.75kW, 1Ø, 240V?
41.67A
What is the demand load, in amps, for a single circuit supplying one wall-mounted oven rated 11.75kW, 1Ø, 240V, and a countertop cooking unit rated 9.6kW, 1Ø, 240V?
48.33A
At a minimum, a 60' long show window would need _____ receptacles.
5
The voltage drop for a 480V, 3Ø circuit with a load of 26.5A, using No. 8 stranded copper conductors at a circuit length of 145
5.18V
Load calculations for circuits supplying lighting units with ballasts are based upon _____.
the ampere ratings of the ballasts
The voltage drop between the point of service and the farthest outlet in a branch circuit should not exceed _____.
3%
What is the total load, in VA, for two small appliance branch circuits in a single-family dwelling?
3,000VA
A warehouse has 12,500 ft2 of floor area. What is the estimated general lighting load in VA?
3,125
What is the load, after applying the appropriate demand factor, for six pieces of commercial kitchen equipment with a total VA rating of 54,000VA?
35,100VA