All questions and answers are based on the 2026 NEC.

Q1: Fill in the blank. The power supply to a mobile home shall be a feeder assembly consisting of not more than one listed _____ mobile home power-supply cord or a permanently installed feeder.

a) 30A

b) 40A

c) 50A

d) 100A

Q2: Fill in the blank. If used to splice service conductors, _____ must be marked “suitable for use on the line side of service equipment” or equivalent.

a) devices for splices and taps

b) power distribution blocks

c) pressure connectors

d) all of these

Q3: Fill in the blank. Aluminum electrical metallic tubing (EMT) shall be provided with approved supplementary corrosion protection where encased in concrete or in direct contact with _____.

a) concrete

b) earth

c) masonry

d) any of these

Q4: Fill in the blank. Where located in a remote location, a transformer disconnecting means shall be _____, and its location shall be field marked on the transformer.

a) accessible only to qualified persons

b) accessible to unqualified persons

c) lockable

d) readily accessible

Q5: Fill in the blank. Disregarding the exception, the smallest copper overhead service conductors allowed for a service are _____ AWG.

a) 8

b) 6

c) 4

d) 2

Q6: Which of these methods is allowed for identifying grounded conductors 6 AWG and smaller?

a) gray outer finish

b) white outer finish

c) white outer finish with a tracer thread

d) any of these

Answers:

Q1: c) 50A

According to Sec. 550.10(A), "The power supply to the mobile home shall consist of not more than one listed 50A mobile home feeder assembly or a permanently installed feeder."

Q2: d) all of these

Section 230.46 requires that devices for splices and taps, power distribution blocks, and pressure connectors shall "be marked or identified as “suitable for use on the line side of service equipment” or equivalent."

Q3: b) earth

Per Sec. 358.10(B)(2): "Aluminum EMT shall be provided with approved supplementary corrosion protection where encased in concrete or in direct contact with the earth."

Q4: c) lockable

Section 450.16 states, "Where located in a remote location, the disconnecting means shall be lockable open in accordance with Sec. 110.25, and its location shall be field marked on the transformer."

Q5: a) 8

According to Sec. 230.23(B), "The conductors shall not be smaller than 8 AWG copper or 6 AWG aluminum or copper-clad aluminum."

Q6: d) any of these

Section 200.7(A) lists gray outer finish, white outer finish, and white outer finish with a tracer thread as permittable means for identifying grounded conductors 6 AWG and smaller.