Article By Todd Fries, Marketing Manager of Identification Systems at HellermannTyton North America
Labeling continues to be a high interest subject within the PV industry. With the new requirements outlined in the National Electrical Code (NEC 2014) and the current International Fire Code (IFC 2012), it has become apparent that the road to standardized labeling is being paved within the new codes and standards. The new standard finally provides some synergy between the IFC and NEC in regards to labeling a PV system, which will lead to better education, more awareness of labeling requirements and a drive to achieve durable and long-lasting labeling that can withstand continued ultraviolet (UV) exposure.
First, the NEC and IFC do not define a particular method of marking the infrastructure. In fact, one of the more important and key changes in the new NEC 2014 code is that the use of the word “label” is now included in the definition of marking formats. Article 110.21 says: “The Label shall be suitable for the environment where it is installed.” This is important because many Authority Having Jurisdictions (AHJ) are still trying to require the use of engraved plates that may not be rated for continuous outdoor use. The labeling technology available today is far more UV stable than even engraved plastic. In addition, there are requirements for reflective labels by both the IFC and NEC that cannot be satisfied with engravings.
In order to come closer to general market specifications, the new NEC 2014 code now requires that any field applied labels, warning(s), and markings should comply with ANSI Z535.4. This is found in article 110.21(B) for Field Marking. What this means is that any label that is defined specifically as a Danger, Warning, or Caution label must follow the labeling format as defined by ANSI Z535.4 unless specified otherwise in Article 690.
An example of such labeling would appear as follows:
In the new 2014 code, there are some exceptions to this rule. Exceptions include several labels that must be red with white lettering and must be reflective.
The first label is a conduit marker that must be applied every 10 feet, at every turn, above and below penetrations, and on all exposed raceways, cable trays and other wiring methods. In the new NEC 2014 code, these labels must be red with white text that is at least 3/8 in. tall and reflective so that they are clearly visible in the beam of a flashlight.
Per article 690.31(E)(3), the label is to be printed with the following text:
WARNING: PHOTOVOLTAIC POWER SOURCE.
This matches the wording and format design as defined in the current IFC 2012 standard. Again, the intent of the regulatory committee was to synergize with the IFC where possible.
Within NEC 2014, there also is a brand new requirement that necessitates a PV system to have a rapid shutdown switch that will reduce the PV system to 30vdc within 10 seconds. In article 690.56(B), each rapid shutdown switch shall be permanently marked to identify it as a Photovoltaic System Equipped with Rapid Shutdown using white lettering that is at least 3/8 in. tall on a red background and shall be reflective.
The updated standards open the door for the acceptable use of high-quality labeling products that are designed to meet the critical UV exposures.
There is no right or wrong answer on marker selection as long as the installer is meeting the requirements of the AHJ in all instances. The trend is that labeling products with specialized features, such as reflectivity, are the vanguard of the new era. Many changes are sure to come as the industry advances and labeling will have to adapt to those changes to become a standard that everyone can define and implement now and in the future.
HellermannTyton North America