Any product that utilizes and produces electricity needs to be regulated with a strict set of standards, and solar panels are no different. The National Electric Code, established by the National Fire Protection Association, a private trade association, codifies the rules for installing, operating and maintaining solar panels in a variety of settings, from residential roof tops to ground-level arrays.

Despite the word "national" in the code, there is no federal law in place mandating the implementation and adoption of the NEC. However local governments and municipalities across the country do use the NEC either in full, or slightly amended, based on the specific circumstances for a particular jurisdiction.

The NEC covers nearly every aspect of solar PV products and installation. Some of the areas the code includes, but are not limited to:

  • Fire classifications
  • Roof-mounted installations
  • Roof live load
  • Building-integrated photovoltaic products
  • Photovoltaic shingles
  • Deck requirements and slope
  • Ice barriers
  • Underlayment and high winds
  • The size of a solar array

In addition to these covered areas, the codes also include specifications for access to solar panels, which is important for first responders in case of a major problem.

Shifting energy dynamics

Originally established in 1896, the NEC focused on the service point, the spot where the utility's responsibility ended and where the electricity entered the customer's property. For more than 100 years, this method sufficed since utilities generated and distributed essentially all of the electricity in the country. Big utility-owned power plants feeding electricity into a network of transmissions lines had their own regulations and industry standards to follow, but when that electricity made its way to the consumer, there needed to be protections in place. 

However, since the advent of decentralized energy production - particularly in the solar sector - the NEC needed to be upgraded to meet the demands of the changing electrical landscape. Due to the growth in units and size of consumer-owned power generation, the NEC code-making panels began to take into consideration a new landscape of systems and considerations. This upgraded NEC has had clear benefits for energy production, as it has made great strides in creating requirements for wiring, overcurrent protection and grounding for consumer-owned energy generators.

Electrical codes causing some confusion

Why the NEC might seem difficult to understand at first and even slightly confusing after an initial read-through, the main theme of these codes is to ensure the safety of the solar system and to protect the end users and firefighters from any potential damages. Despite the best intentions of the NFPA in creating a standard for maintaining a high level of safety and consistency for installing, operating and maintaining solar panels, not every authority or PV professional interprets the codes the same way. 

As reported by Solar Power World Online, the NEC rule 690.12, in particular, aimed at protecting first responder safety, includes rapid shutdown and other provisions that have been causing confusion among PV professionals and local authorities. Pure Power also highlighted the complex nature of this rule and how it may leave some people feeling confounded. 

Bill Brooks, principal of Brooks Engineering and chair of the task group that authored the NEC photovoltaics provision, noted that because this is first version of 690.12, the panel intentionally made the code language brief and didn't want to dictate how the PV community would do things, according to Solar Power World. 

"We have run into situations where inspectors have enforced the code incorrectly," Brooks said. "Some are fine, but others have misunderstood requirements in the direction of oversimplification and didn't know what they were approving. Others have misread the requirements and demanded all kinds of ridiculous things."

The NEC assumes those authorities adopting the rules will have some familiarity with solar technology, however that isn't always the case. This can leave room for misunderstandings of the code. Further, since the codes are not mandatory or completely uniform, an inspector might want a solar installation one particular way based on his or her interpretation, while across the street in a different jurisdiction, the inspector might have a completely different understanding of what the code requires.

How Trina Solar can help

At Trina Solar, we want to eliminate as much confusion as possible with NEC compliance for customers using our solar panels. Trinaswitch, the next generation in smart module technology, is a cost-effective solution that automatically shuts down the solar system in the event of a power outage and AC loss. The Trinaswitch module meets the 2017 NEC 690.12 Rapid Shut Down compliance standard. 24 different states already have adopted some form of the NEC 690.12 requirements, and more will do so going forward. With this smart module technology, customers, project managers and other end users gain an easy method for complying with the NEC and ensuring the safety of everyone involved.

In addition to the rapid shutdown feature, with a simple changing of the faceplate on the module's junction box, Trinaswitch is easily upgradable to a Trinasmart module, providing great DC optimization and increased string flexibility.

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