3 minute read
RES Technical Corner ECCCNYS
For the article this month we will look into the Energy Conservation Construction Code of New York State (IECC) and how it pertains to the use of occupancy sensors utilizing a manual switch within a corridor. There appears to be some thoughts that these manual switches could defeat the functionality of the occupancy sensors leaving the corridor in complete darkness.
The first concept to grasp is that lighting controls are not even required in corridors per some of the exceptions listed in C405.2 of the IECC. So, what does this mean and why is the energy code allowing the lighting to be on all the time with no controls…?
Vocab word: Night Light (NL)-a lighting fixture with no on or off control - on 24/7.
Can’t we do a little better to save some energy?
Of course we can! We can add occupancy sensors per the Exception listed in C405.2.1.1 which allows occupancy sensors in corridors…BUT…if we do add occupancy sensors then we must have manual control to allow occupants to turn off the lights per one of the requirements of section C405.2.1.1 above.
A misconception is that if we had a manual override, maintained toggle switch (think residential style light switch) and leave the switch in the off position then the occupancy sensor will not work. I believe this to be true if you are using line voltage occupancy sensors with a line voltage switch. However, if you introduce low voltage switching, a power pack and a low voltage occupancy sensor, then the switch will only act as a “state changer”…meaning whatever state the light fixtures are in will be changed to the opposite and will not override the occupancy sensor.
Going one step further to meet the International Building Code (IBC) section 1008.2. The occupancy sensors could malfunction which could leave the egress passageway in complete darkness which would not allow occupants to egress from the building safely…Therefore an option is to add some Night Lights in the corridors along with the occupancy sensor-controlled fixtures and manual switch.
res - technical corner Hopefully this article finds you well and can be used as a reference for your project needs. If anyone would like to contribute to the Rochester Engineer and add an article or would like to request information on a specific topic (not limited to Electrical) just email Brett Eliasz at beliasz@bergmannpc.com. As always, any comments are appreciated! Thank you for reading.
