Electrical Code Calculations lvl 2 Lesson 1- Determining Conductor Ampacity

The neutral conductors of a 4-wire, 3-phase wye circuit, where most of the load is nonlinear and connected to ? , are considered to be current-carrying conductors according to the provisions of Table 310.15(C)(1).

fluorescent lighting 310.15(E)(3)

Three 1/0 AWG XHHW-2 aluminum conductors are installed in a rigid metal conduit, Type RMC, in an ambient temperature of 105°F. All of the conductors are current-carrying conductors. Determine the ampacity of the current-carrying conductors. Calculate to the nearest ampere.

117A

Nine 3/0 AWG THHN aluminum conductors are installed in a three-inch RMC in an area with an ambient temperature of 35°C. Only six of the conductors are current-carrying conductors. Determine the ampacity of the 3/0 AWG conductors for this application. Calculate to the nearest ampere.

134A

Twelve 12 AWG THHN copper conductors are installed in a one-inch EMT in an ambient temperature of 32°C. These twelve conductors are comprised of three 4-wire multiwire branch circuits. The multiwire branch circuits are supplied by a 4-wire, 3-phase, wye-connected system. The major portion of the load for each multiwire branch circuit consists of nonlinear loads. Determine the ampacity of each of the 12 AWG conductors. Calculate to the nearest ampere.

14A

Twenty 10 AWG THWN aluminum current-carrying conductors are installed in the same conduit in an ambient temperature of 30°C. Determine the ampacity of each of the current-carrying conductors. Calculate to the nearest ampere.

15A

Twelve 12 AWG THHN copper conductors are installed in a one-inch EMT in an ambient temperature of 32°C. These twelve conductors are comprised of three 4-wire multiwire branch circuits. The multiwire branch circuits are supplied by a 4-wire, 3-phase, wye-connected system. The neutral conductor in each of these multiwire branch circuits carries only the unbalanced current from the other conductors in each respective multiwire branch circuit. Determine the ampacity of each of the 12 AWG conductors. Calculate to the nearest ampere.

20A

Two 3-phase, 4-wire multiwire branch circuits supply LED lighting loads from a 3-phase, 4-wire, wye system. The branch circuits consist of eight 10 AWG THWN copper conductors installed in EMT in an ambient temperature of 86°F. Determine the ampacity of the 10 AWG conductors in this application. Calculate to the nearest ampere.

25A

Two "A" phase conductors, two "B" phase conductors, and two neutrals are installed as two 3-wire multiwire branch circuits of a 120/208-volt system. They are installed in EMT in an ambient temperature of 30°C. The conductors are 10 AWG THHN copper. What is the ampacity of each of the current-carrying conductors? Calculate to the nearest ampere.

32A

A three-conductor 8 AWG Type NM cable is installed in an area with an ambient temperature of 94°F. Determine the ampacity of the copper circuit conductors. Calculate to the nearest ampere.

40A

Determine the ampacity of six 8 AWG THW copper conductors installed in EMT in an ambient temperature of 30°C. All of the conductors are current-carrying conductors. Calculate to the nearest ampere.

40A

Determine the ampacity of three 8 AWG THWN copper conductors installed in EMT in an ambient temperature of 40°C. All of the conductors are current-carrying conductors. Calculate to the nearest ampere.

44A

Nine 4 AWG THW aluminum conductors are installed in a rigid nonmetallic conduit. Three 8 AWG THW copper conductors are installed in the same raceway for use as equipment grounding conductors. The conductors are installed in an area with an ambient temperature of 30°C, and all of the 4 AWG conductors are current-carrying conductors. Determine the ampacity of the circuit conductors. Calculate to the nearest ampere.

46A

A 3-conductor 8 AWG copper Type MC cable is installed in an area with an ambient temperature of 96°F. The conductors within the cable assembly have THHN insulation, and all three conductors are considered current-carrying conductors. Determine the ampacity of the current-carrying conductors in this application. Calculate to the nearest ampere.

50A

Determine the ampacity of three 8 AWG THWN copper conductors installed in EMT, in an ambient temperature of 30°C. All of the conductors are current-carrying conductors.

50A Table 310.15(B)(16)

Twelve 1 AWG THWN copper conductors are installed in a three-inch EMT in an ambient temperature of 101°F. All of the conductors are current-carrying conductors. Determine the ampacity of the 1 AWG THWN conductors for this application. Calculate to the nearest ampere.

57A

Six 4 AWG THW copper conductors are installed in the same raceway in an ambient temperature of 30°C. All of the conductors are current-carrying conductors. Determine the ampacity of the 4 AWG current-carrying conductors. Calculate to the nearest ampere.

68A

Control circuits are considered to be current-carrying conductors according to the provisions of Table 310.15(C)(1).

False 310.15(B)(3)(a)

The equipment grounding conductor is considered to be a current-carrying conductor according to the provisions of Table 310.15(C)(1).

False 310.15 (B)(6)

The neutral conductor of a 2-wire, single-phase circuit supplying a household refrigerator is considered to be a current-carrying conductor according to the provisions of Table 310.15(B)(3)(a).

True 310.15(B)(3)(a)