Every three years, a new version of the National Electrical Code is released. The cumulative number of changes is always large, which can make it difficult to find the most important changes you should be concerned with. Some changes are rather minor, while other changes are significant—requiring a shift in work practices and procedures. Whatever your level of electrical knowledge, this list will give insight into five of the most important changes to the 2014 National Electrical Code.
1. New Articles: In the 2014 NEC there are four brand new Articles. Two of them are Article 393 and Article 646.
Article 393 applies to low-voltage suspended ceiling power distribution systems. With the explosive growth in alternative sources of energy, coupled with devices using small amounts of power, Article 393 was created to address the installation of low voltage suspended ceiling power distribution systems. These systems have a busbar support system that distributes power to multiple Class 2 power supplies. The suspended ceiling grid supports a finished ceiling surface, as well as attached utilization equipment.
Article 646 applies to modular data centers. Modular data centers are different than data centers as defined in Article 645. They can be thought of as a crossbreed piece of equipment. Both are customizable and scalable, but modular data centers are not usually permanently installed. This makes modular data centers incompatible with the requirements of Article 645, since wiring in IT rooms can only be done if all of the requirements of Section 645.4 are met. Article 646 was created to address this issue, and contains all of the requirements and specifications for installing and maintaining modular data centers. This includes requirements for supply conductors, field wiring, work space requirements, nameplate data, overcurrent protection, backup and primary power sources, and HVAC installation.
The other two new Articles, 728 and and 750, will be discussed in the Part 2 of this blog.
2. Changes in Voltage Threshold: In the 2014 NEC, the voltage threshold has been moved from 600 up to 1,000 in many locations. While this change in voltage has occurred in multiple NEC applications, it was mainly introduced for solar PV equipment installations. This equipment often operates at much higher volts than the previous threshold. The new threshold will support future installations of PV equipment, as well as many other applications.
3. Field-Applied Hazard Markings: In the 2014 NEC, there have been significant changes to requirements for field-applied hazard markings. Section 110.21(B) is a brand new addition that details certain requirements that labels must meet in order to be approved. This provides consistency to all of the Code sections requiring these labels. In the 2014 NEC, wherever caution, danger, or warning signs are required, there will now be a reference to Section 110.21(B), unless special circumstances exist that require different standards. This means that all hazard markings will adhere to the same requirements, creating uniformity and consistency.
4. GFCI and AFCI Protection: As in previous editions, GFCI and AFCI protection requirements have been expanded. In dwelling units, GFCI protection requirements have been expanded into laundry areas, kitchens, bathrooms without sinks, and for dishwashers. AFCI protection is now required for branch circuits that supply outlets or devices in dormitory units, kitchens, and laundry areas. In addition, the AFCI must be installed in a readily accessible location.
5. Installation of Grounding Electrode Conductors: The requirements for installing grounding electrode conductors have been changed to address common confusion relating to their method of installation. When installing grounding electrode conductors, Code users would often adhere to the requirements of “Direct Buried Cables or Conductors” found in Table 300.5. This would result in installations that threatened the integrity of the grounding electrode conductor. Changes to the 2014 NEC help prevent confusion as it relates to installation of grounding electrode conductors.
These are just a few of the important changes in the 2014 National Electrical Code. There are many other changes that have an effect on important electrical work.