Code Hunter: Connections, 2017 NEC

1) Where a tightening torque is indicated as a numeric value on equipment or in installation instructions provided by the manufacturer, a __________ torque tool shall be used to achieve the indicated torque value, unless the equipment manufacturer has provided installation instructions for an alternative method of achieving the required torque.

  1. Listed
  2. Digital
  3. Certified
  4. Calibrated

2) Premises wiring shall not be __________ connected to a supply system unless the latter contains, for any grounded conductor of the interior system, a corresponding conductor that is grounded.

  1. Directly
  2. Electrically
  3. Permanently
  4. Magnetically

3) The temperature correction and adjustment factors shall be permitted to be applied to the ampacity for the temperature rating of the conductor, if the corrected and adjusted ampacity does not exceed the ampacity for the temperature rating of the __________ in accordance with the provisions of 110.14(C).

  1. Enclosure
  2. Equipment
  3. Connector
  4. Termination

4) Nonconductive coatings (such as paint, lacquer, and enamel) on equipment to be grounded shall be removed from threads and other contact surfaces to ensure good electrical continuity or be connected by means of fittings __________ so as to make such removal unnecessary.

  1. Listed
  2. Welded
  3. Designed
  4. Identified

5) A clamp assembly that incorporates a cable termination for the cable conductors shall be listed and __________ for use with specific nonmetallic boxes.

  1. Marked
  2. Suitable
  3. Identified
  4. Approved

6) Terminations on __________ cables rated over 600 volts, nominal, shall be accessible only to authorized and qualified personnel.

  1. Fixed
  2. Flexible
  3. Portable
  4. Exposed

7) A luminaire shall be permitted to be connected with a cord terminating in a __________ attachment plug or busway plug.

  1. Rated
  2. Locking
  3. Permanent
  4. Grounding-type

8) A multiwire branch circuit consists of two or more ungrounded conductors that have a voltage between them, and a grounded conductor that has equal voltage between it and each ungrounded conductor of the circuit and that is connected to the neutral or grounded conductor of the system.

  1. True
  2. False

9) Round boxes are required to be used where conduits or connectors requiring the use of locknuts or bushings are to be connected to the side of the box.

  1. True
  2. False

10) For isolated ground receptacles, the receptacle grounding terminal is required to be connected to an insulated equipment grounding conductor run with the circuit conductors.

  1. True
  2. False

Bonus Question

[mlw_quizmaster quiz=3]

Answers

1) D, Calibrated. Section 110.14(D) is new language added for the 2017 NEC. Although torque tool use has always been required based on the language in 110.3(B), this new language clarifies the requirement and adds an explicit requirement for torque tool calibration. The code-making panel rationale in First Revision 40 stated, “Use of proper torque tools is essential to verify that terminations are properly made and the equipment will function properly throughout its life cycle. Testing has shown that installers use the wrong torque values in up to 75% of installations unless a torque measuring tool is used.”

2) B, Electrically. This requirement is found in 200.3, which goes on to say “For the purpose of this section, electrically connected shall mean connected so as to be capable of carrying current, as distinguished from connection through electromagnetic induction.”

3) D, Termination. Conductors are tested and listed at the temperature marked on the conductor, and 310.15(B) allows the use of insulation rated at a temperature higher than the termination limit. However, the final allowable ampacity of the conductor is limited to the lower of either the adjusted and corrected ampacity or the ampacity value associated with a conductor at the termination temperature

4) C, Designed. This requirement is found in 250.12, and it requires the removal of any materials that might interfere with a solid connection between a metallic surface and a grounding connection. For example, paint on an enclosure must be removed at the connection point prior to installing a grounding connector.

5) A, Marked. This requirement is found in 314.16(B)(2). Fittings listed for use with cable and conduits are listed to UL 514B Conduit, Tubing and Cable Fittings.

6) C, Portable. This requirement is found in 400.36; Article 400 includes requirements for Flexible Cords and Flexible Cables. “Qualified person” is defined in Article 100 as “One who has skills and knowledge related to the construction and operation of the electrical equipment and installations and has received safety training to recognize and avoid the hazards involved.”

7) D, Grounding-type.  This requirement is found in 410.62(C)(1)(a), and the language was clarified in the 2017 NEC.

8) A, True. This information is found in the Article 100 definition for “Branch Circuit, Multiwire.”

9) B, False. Section 314.2 states that round boxes are not permitted to be used where conduits or connectors requiring the use of locknuts or bushings are to be connected to the side of the box.

10) A, True. This requirement is found in 250.146(A). Isolated ground receptacles are installed for the reduction of electrical noise (electromagnetic interference) on the grounding circuit.

Christel Hunter and Randy Hunter
Christel Hunter is vice president of standards for Cerro Wire. Chris serves as President for the Southern Nevada Chapter of IAEI. Chris also serves on NEC CMP-6 and CMP-13, NFPA 921, NFPA 70B, NFPA 73 and UL STPs 62, 83, 719 and 4703. Chris is a Professional Safety and Health Officer, Certified Standards Professional, Master Electrician, and LEED Accredited Professional. Randy Hunter is an instructor and consultant specializing in electrical code and installations, and co-owner of Hunter Technical Services. He holds ten inspections certifications from IAEI and ICC. He has been a master electrician since 1988.