What are the new NEC Short Circuit Current Ratings requirements?
The NFPA 70, NEC 2002 edition, Article 285.6, introduced a new requirement that the SPD be tested and labeled with a short circuit current rating equal to, or greater than the available fault current at that point in the system. At this point in time, TVSS devices passing through UL 1449, have inherently been Listed to short circuit current ratings (SCCR) of 5-25 kA. This new requirement is currently being reviewed by UL 1449 as they consider how best to test to higher short circuit fault currents. Products can be Listed with higher ratings if the manufacturer has specifically requested this. This section will be revised once the new UL requirements are published.
