Test Your Code IQ — September 2025

Courtesy of www.MikeHolt.com.

All questions and answers are based on the 2023 NEC.

Q1: In information technology rooms, the remote disconnect controls shall be located at approved locations that are _____ in case of fire to authorized personnel and emergency responders.

a) accessible

b) readily accessible

c) secured

d) restricted

Q2: For circuit sizing calculations of PV systems without adjustment and/or correction factors, the minimum conductor size must have an ampacity not less than the maximum currents calculated in Sec. 690.8(A) multiplied by _____. 

a) 75%

b) 100%

c) 125%

d) 150%

Q3: Interior metal water piping that is electrically continuous with a metal underground water pipe electrode and is located not more than _____ from the point of entrance to the building, as measured along the water piping, is permitted to extend the connection to an electrode(s).

a) 2 ft

b) 3 ft

c) 4 ft

d) 5 ft

Q4: Receptacles mounted in boxes flush with the finished surface or projecting beyond it shall be installed so that the mounting yoke or strap of the receptacle is held rigidly against the _____.

a) box or box cover

b) faceplate

c) finished surface

d) bonding connection

Q5: Where ungrounded supply conductors are paralleled in two or more raceways, the supply-side bonding jumper for each raceway shall be based on the size of the _____ in each raceway.

a) overcurrent protection for conductors

b) grounded conductors

c) largest ungrounded supply conductors

d) sum of all conductors

Q6: No conductor shall be used where its _____ temperature exceeds that designated for the type of insulated conductor involved. 

a) operating

b) ambient

c) highest

d) lowest

Answers:

Q1: b) readily accessible

Per Sec. 645.10(A)(1): "Remote disconnect controls shall be located at approved locations readily accessible in case of fire to authorized personnel and emergency responders."

Q2: c) 125%

Section 690.8(B)(1) states, "The minimum conductor size with an ampacity not less than the maximum currents calculated in Sec. 690.8(A) multiplied by 125%." 

Q3: d) 5 ft

According to Sec. 250.68(C)(1), "Interior metal water piping that is electrically continuous with a metal underground water pipe electrode and is located not more than 5 ft from the point of entrance to the building, as measured along the water piping, is permitted to extend the connection to an electrode(s)."

Q4: a) box or box cover

Per Sec. 406.5(B): "Receptacles mounted in boxes that are flush with the finished surface or project therefrom shall be installed such that the mounting yoke or strap of the receptacle is held rigidly against the box or box cover."

Q5: c) largest ungrounded supply conductors

As stated in Sec. 250.102(C)(2)(1), "An individual bonding jumper for each raceway or cable shall be selected from Table 250.102(C)(1) based on the size of the largest ungrounded supply conductor in each raceway or cable.”

Q6: a) operating

Section 310.14(A)(3) states, "No conductor shall be used in such a manner that its operating temperature exceeds that designated for the type of insulated conductor involved." 

These materials are provided by Mike Holt Enterprises in Leesburg, Fla. To view Code training materials offered by this company, visit www.mikeholt.com/code.