Code Change Summary: New code section to address the wiring of Class-2-powered emergency lighting systems.

Over the last few years, Power over Ethernet (PoE) emergency lighting systems using Class 2 power sources and Class 2 wiring has become a prevailing alternative to line voltage installations.

Benefits of PoE emergency lighting systems include:

• Less energy consumption especially for installations where the normal area PoE lighting also provides emergency illumination when normal power is not present.
• Less overall weight added to the building since Class 2 wiring methods are lighter than line voltage cables and conduits.
• The ability to monitor remotely and receive alerts through software as to the performance of the emergency lighting system.
• Flexible software options which could allow building maintenance personnel to pull up a schematic of the entire emergency lighting system layout for each floor level at a glance and see if any emergency luminaires have failed. This could greatly reduce the time needed during an annual fire inspection versus having the fire inspector walk through each floor of the building using the push-to-test feature on every single emergency light.
• Reduced maintenance cost over the life of the system.

For years the requirements in the NEC^® addressing emergency lighting have been tailored to line voltage emergency lighting installations with little to no language directed towards other options.

In the 2023 NEC^®, new Section 700.11 provides a good start for introducing new language pertaining to Class-2-powered emergency lighting systems. It is likely that this new language will see continuing changes with each future NEC^® code cycle as these systems become more common.

Below are some highlights from Section 700.11:

• Section 700.11(B) requires emergency circuits to be permanently marked to be readily identified as a component of an emergency circuit or system by the following methods:
  • All boxes and enclosures for Class 2 emergency circuits shall be permanently marked as a component of an emergency circuit or system.
  • Exposed cable, cable tray, or raceway systems shall be permanently marked to be identified as a component of an emergency circuit or system, within 3 feet of each connector and at intervals not to exceed 25 feet.
• Section 700.11(C) covers Separation of Circuits and requires Class 2 emergency circuits to be wired in a listed, jacketed cable or with one of the wiring methods of Chapter 3. If installed alongside nonemergency Class 2 circuits that are bundled, Class 2 emergency circuits must be bundled separately. If installed alongside nonemergency Class 2 circuits that are not bundled, Class 2 emergency circuits must be separated by a nonconductive sleeve or nonconductive barrier from all other Class 2 circuits. Separation of circuits shall comply with 725.136.
• Section 700.11(D) applies to wiring protection. Wiring shall comply with the requirements of 300.4 and be installed in a raceway, armored or metal-clad cable, or cable tray unless the exceptions apply.
  • Exception 1: Wiring that does not exceed 6 feet in length and that terminates at an emergency luminaire, or an emergency lighting control device is not required to comply with 700.11(D).
  • Exception 2: Wiring in locked rooms or locked enclosures that are accessible only to qualified persons is not required to comply with Section 700.11(D).
• The Informational Note makes it clear that locked rooms accessible only to qualified persons can include locked telecommunications rooms, locked electrical equipment rooms, or other access-controlled areas.

Below is a preview of the NEC^®. See the actual NEC^® text at NFPA.ORG for the complete code section. Once there, click on their link to free access to the 2023 NEC^® edition of NFPA 70.