Code Change Summary: A new definition of a Directly Controlled Luminaire was added in Section 700.2.
During the 2014 code cycle, the following code language was added in 700.24 to address directly controlled luminaires: Where emergency illumination is provided by one or more directly controlled luminaires that respond to an external control input to bypass normal control upon loss of normal power, such luminaires and external bypass controls shall be individually listed for use in emergency systems.
Along with the proposal to accept the new language was another proposal to add the definition of a directly controlled luminaire to the definitions in 700.2. For some reason, Section 700.24 made it through but the new definition did not.
In the 2017 NEC®, the definition was added. A Directly Controlled Luminaire is an emergency luminaire that has a control input for an integral dimming or switching function that drives the luminaire to full illumination upon loss of normal power. Basically, in theatres and similar locations, all the lights can be dimmed during the performance, even the emergency lighting and exit signs.
In the event of a power outage, electronic circuitry in the luminaire automatically takes the emergency luminaire to full brightness regardless of the dimmer switch position.
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 2017 NEC® edition of NFPA 70.
2017 Code Language:
N Luminaire, Directly Controlled. An emergency luminaire that has a control input for an integral dimming or switching function that drives the luminaire to full illumination upon loss of normal power.
N Informational Note: See ANSI/UL 924, Emergency Lighting and Power Equipment, for information covering directly controlled luminaires.
Which of the following is true of a directly controlled luminaire?
Please register or sign in for electrical continuing education courses. If you were already signed in, your session probably expired, please sign back in. |