Violation #1. Conductor Box Fill Issues

Ask some installers how many conductors an electrical device box can contain, and you might get the answer “as many as I can get in the box and still get the switch or receptacle to fit.” Hopefully, this is not the case in your area of the country. All boxes must be large enough to provide sufficient free space for all enclosed conductors to prevent overcrowding and possible physical damage. Information is provided in Sec. 314.16 to assist the installer and the inspector in determining the correct conductor fill for these installations.

Violation # 2. Bored Holes in Wood Framing

One of the most common violations in residential installations involves the installation of nonmetallic (NM) cables through wood framing. The International Residential Code (IRC) contains a lot of information about the removal of framing material through notching or boring methods. This information is needed to ensure that the tradesperson does not remove too much of the framing material, thus weakening the structural integrity of the building. The NEC also provides guidance in Sec. 300.4 on protecting these cables against physical damage. A steel plate is needed where the edge of the hole is less than 1¹/₄ in. from the nearest edge of the wood member. The steel plate must be at least ¹/₁₆ in. thick (unless the plate is listed), and long/wide enough to cover the area of the NM cable. 

Violation # 3. Improper Torquing of Terminations

The tightening of conductors is sometimes taken for granted. Many electricians have been taught that their elbow contains this “magical” ability to sense when the appropriate amount of force has been applied to the tool tightening the electrical termination. This was tested a few years ago at a trade show by a wiring manufacturer. The attendees were mostly all seasoned electricians. They were given an opportunity to tighten electrical terminations with a standard wrench to the level they thought it was tightened properly. A staggering 78% of these terminations were under torqued. Now think how many times you have done exactly that same thing. This is why torquing and using the proper tools is important to the electrical safety of the installation.

Requirements located in Sec. 110.14(D) specify an approved means to be used to reach the torque value for electrical terminations. These values are indicated on the electrical equipment or can be found within the installation instructions provided by the manufacturer. Examples to determine that the proper torque has been applied include torque tools or devices such as shear bolts or breakaway-style devices with visual indicators.

Each state or electrical jurisdiction will need to be consulted on how they want to verify the installer has conducted the required torquing of termination for their electrical installation. This varies from watching an installer use a torquing tool correctly on some of the terminations to requiring a signed document attesting that the electrical terminations have been torqued per the manufacturer’s requirements. It is imperative that the electrical professional knows how to properly utilize these tools. 

Violation #4. Lack of Proper Circuit Identifications for Panelboard Schedules

One critical item that needs to be completed on most electrical projects is a properly and legibly labeled circuit directory. This ensures that the homeowner, business owner, or maintenance person knows which circuit breaker controls each of the branch circuits in the dwelling/building. Requirements found in the Sec. 408.4(A) will help you with this process. Make sure that the labels do not depend on transient conditions. For example, David, Tim, or Thomas may currently occupy a bedroom in the house but may not in the future. If these are bedrooms or office locations, label the circuit directory appropriately, such as NW second-floor bedroom or first-floor master bedroom. In addition, do not put the symbols used by the electrical industry down for receptacles and switches. It is almost guaranteed that the homeowner or office tenant will not know the meaning of these symbols.

Violation #5. Grounding and Bonding Between the Service Disconnect and Feeder Panelboard

Grounding and bonding of electrical equipment is by far one of the most misunderstood requirements in the NEC. Many times, it is because someone was taught something incorrectly, and they have continued doing it over and over throughout their careers. It starts with the use of properly defined terms for the various components.

Not everything used for grounding and bonding can be referred to as “that ground wire.” Many questions asked during IAEI meetings or via email must first go through the proper use of definitions, which are listed in Art. 100 of the NEC.