Voltage Thresholds — Increased from 600 Volts to 1000 Volts

The NEC Correlating Committee reactivated the High Voltage Task Group for the 2014 NEC development process and provided a specific assignment to review the entire NEC and submit proposals that raise the 600-volt threshold to 1000 volts. The reason behind this global effort relates primarily to some output circuits from renewable energy sources often exceeding the 600-volt level. The problem is significant enough that the NEC Correlating Committee determined the need to consider proposing increasing the long-standing 600-volt threshold to 1000 volts, Code wide. The Task Group submitted proposals to each technical committee to consider and act on in the 2014 NEC development cycle. As these proposals were addressed by each committee, it became clear that many proposed revisions would have no impact, and were accepted. However, some technical committees determined these proposed changes would require substantial work that would require much more time and research to complete than the 2014 cycle would permit, accordingly they rejected the proposals.  The result in the 2014 NEC is that in many rules, where the voltage level was previously 600 volts, it has been changed to 1000 volts. The NEC Correlating Committee understands that these revisions are necessary as the industry is evolving, however, concedes this project is extensive and will extend into the 2017 NEC cycle and perhaps beyond. The assigned High Voltage Task Group also continues to be active in incorporating many other new medium and high voltage requirements throughout the NEC to close gaps and incorporate adequate NEC provisions for those installations and systems that are no longer governed by the National Electrical Safety Code^® (NESC^®) or applicable Utility Regulations. Wiring and equipment installed on the line side of the service point is typically not covered by the NEC, while electrical installations on the load side of the service point are usually covered by the NEC.