What minimum size aluminum THW grounded service-entrance conductor is required for a single-family dwelling unit with the calculated neutral load of 85 amperes supplied from a 120/240-volt system?
2 AWG
A duplex Ground Fault Circuit Interrupter (GFCI) receptacle is installed using a rigid nonmetallic conduit and a metal device box. Two 12 AWG conductors enter the box and are spliced to two 12 AWG conductors leaving the box and to two pigtails, which feed the receptacle. A bare 12 AWG equipment grounding conductor enters the box, connects to the box grounding screw, and continues through the box. What is the minimum size metal device box for this installation?
3 in. × 2 in. × 31/2 in. device box
What is the maximum standard size overcurrent protective device permitted to protect a 1 AWG THHW-2 conductor when terminated to equipment rated 75°C?
150 Amp
Which should be determined first after the continuous and non-continuous loads are calculated, the size of the overcurrent protective device or the size of the conductor?
Overcurrent protective device first, then conductor.
What is the minimum length for a pull box when four runs of 3 1/2" RMC are installed adjacent to each other and are run straight through the same box, provided that the conductors are sized 4 AWG or larger and are not spliced?
28"
What is the maximum percentage of fill for a conduit with only one conductor? Provide Article of code for points.
53%
Chapter 9 Table 1
One 10-2 Nonmetallic-Sheathed Cable is installed in an area with the ambient temperature of 40°c. What is the ampacity of the current-carrying conductors?
30 Amps
What minimum size copper THW ungrounded service-entrance conductors are required for a single-family dwelling unit with the calculated load of 150 amperes supplied from a 120/240-volt system?
1 AWG
What is the maximum number of 12 AWG THWN-2 copper conductors permitted in a 1" EMT?
26
This happens to resistance when ambient temperature decreases.
What is decreases?
This NEC code prohibits exceeding the maximum operating temperature of an insulated conductor?
310.14(A)(3)
What is the resistance of 400 feet of 2 AWG uncoated stranded copper conductor? Round the FINAL answer to four decimal places.
.0776 ohms
Two 12 AWG THWN, three 4 AWG THWN, and two 10 AWG THWN copper current-carrying conductors are installed in the same conduit in an area with an ambient temperature of 30°C. What is the ampacity of the 4 AWG conductors?
59.5 A
What is the minimum size EMT needed for five 2 AWG THW conductors, eight 6 AWG THW conductors, and four 8 AWG THW conductors, when all conductors are of the compact aluminum type?
2 1/2" EMT
A 12-3 (plus ground) copper SE cable is installed to supply a 120/240-volt dryer receptacle in a dwelling unit. The cable is constructed with RHW insulation and is installed in direct contact with thermal insulation. What is the ampacity of the cable?
20 Amps
What is the voltage drop on a single-phase, 480 volt branch circuit supplying a 100-ampere load at a distance of 180 feet, with 1/0 AWG THWN copper uncoated conductors at maximum operating temperature? Round the FINAL answer to two decimal places
14.36 volts
What is the maximum length of a single-phase, 120-volt branch circuit supplying a 20-ampere load with 10 AWG solid copper conductors permitted without exceeding a voltage drop of 3.0 V? Round the FINAL answer to two decimal places.
60.35ft