Why the focus shifted?
Before any lightning protection standards could be developed, it was important to assess the extent of damage to facilities caused by lightning strikes. For years, the National Electrical Manufacturers Association (NEMA) Lightning Institute has been trying to obtain this information from nationally recognized insurance companies. The goal of obtaining the information was to assess the extent of the threat of lightning damage so that the organization could provide appropriate guidance to front-line installers to prevent damage from occurring in the first place.
The problem was that insurance companies were reluctant to provide information about compensation claims because they didn’t want to let their competitors know how much they were paying them. To overcome this reluctance, NEMA finally decided to send surveys directly to commercial and industrial customers to gather data independently. The response to the survey was so overwhelming that NEMA followed up with a more detailed survey to dig deeper into the data.
The result was a widely publicized 2014 NEMA report that detailed the damage caused by surges in structures such as long-term nursing facilities, hospitals, and other industrial buildings. As a result of NEMA’s findings, significant changes were made to the 2017 NEC, including the addition of several specific provisions to address the overall safety of facilities.
Once these guidelines were in place, the National Emergency Management Authority turned its attention to promoting changes in residential housing, a sector that had previously been low on the priority list.
from scientifict side
With multiple dwelling units, there are inductive loads such as HVAC systems, chillers, and other motors that can cause transient voltages. A surge protector (SPD) in service will not be an effective way to mitigate transient voltages because the problem may occur in only one of the multiple units. This failure can cause transient voltages that travel to the other units. With a surge protector installed in each dwelling unit, transient voltages are better handled regardless of the source.
As electricians become more educated about SPDs, UL 1449, and the IEEE Installation Guide, home protection will become a standard product. As home automation becomes more widespread, network-interfaced SPDs will also become more common.
The requirements in Section 230.67 of the 2020 National Electrical Code are designed to protect residential dwellings from power surges caused by lightning strikes and utility failures. Like the initial changes for commercial utilities, the new residential guidelines are a good first step—but more needs to be specified in future updates. There are more processor-powered devices in homes today than ever before. Between connected TVs, home security systems, laptops, and refrigerators, there’s hardly a room in the home that doesn’t have electronics. This increased electrification of the home is reflected in the financial cost to insurance companies for surge protection damages.
In the mid-1990s, the number of claims filed with insurance companies that resulted in overcurrent damages was more frequent, but the average damage claim amount remained around $4,000. By the first decade of the 21st century, the number of overcurrent protection claims had declined, but the amount of damages reported had risen dramatically to an average of $15,000 per claim.
What do the new requirements mean for you?
The 2020 National Energy Regulations specifically require SPDs to be installed on all services that supply residential units. Whether it is a single-family home, a two-family or three-family dwelling, or an apartment building, SPDs are now required. Determining exactly where to install an SPD has led to some debate in the industry.
One item that some electricians see as a disadvantage is the suggestion that an SPD be installed in the meter panel or disconnected several feet from the service panel that contains the circuit breaker. After all, the utility meter receptacle is not part of the service, and all components between the meter receptacle and the service panel are defined as part of the service. But others believe (for complete protection) that an SPD should be installed in the service panel, not the meter panel.
Some industry professionals note that there are no guidelines for maximum surge protection for residential dwellings. For some industries that use the same utility voltage as residential dwellings, the engineering community requires a minimum rating associated with UL 1449, which includes a short circuit current rating and a nominal discharge current rating. In most cases, there is also a specified maximum surge rating. In lightning protection systems, there are minimum UL 1449 ratings required, but there are lightning protection devices in the residential sector that do not meet these specifications for these specific engineering projects or lightning protection systems.
As with all regulations, the NEC will continue to evolve, addressing the protection of these and other vulnerable areas. Better installation practices are also expected, and UL 1449 classifications for service entry requirements will be considered more carefully.
When will countries adopt NEC 2020?
At the time of this writing in August 2021, 12 states have adopted the 2020 NEC in their jurisdictions, including the regulations for SPDs. Another 12 states are currently in transition. The remaining states are operating under previous versions of the NEC or other electrical codes.
Fortunately for consumers, it doesn’t necessarily require a state-level mandate to adopt the provisions of the 2020 National Energy Act. Municipalities, counties, and other jurisdictions can adopt the latest NEA regulations on their own—and often do. While a hybrid approach isn’t ideal, the more jurisdictions that adopt the 2020 National Energy Act, the more likely it is that the state in which you operate will eventually adopt it as well.
As the U.S. economy continues to electrify and new forms of power generation (renewables) are developed, it will become more important than ever to protect this valuable infrastructure from unwanted surges. And as damage claims continue to rise, insurance companies will begin to impose direct damage reports on particularly vulnerable residential dwellings.
The 2020 NEC updates are an excellent first step in simplifying regulations for metal detectors, and it will be interesting to see where they go in the future.
Rick Severson is North America Boom Market Manager For nVent ERICO.
