emergency lighting

bdmulk

New member
My employer has asked to install an emergency lighting system in our facility. My immediate boss has asked me to to install a switch for each exit sign and emergency light,, however I am thinking that switching is not allowed for an emergency lighting system. Is switching allowed in an emergency lighting system?
 

iwire

Moderator
Staff member
Location
Massachusetts

Dennis Alwon

Moderator
Staff member
Location
Chapel Hill, NC
Occupation
Electrical Contractor
In general emergency and exit lighting is not required to be on when the building is unoccupied.

You can switch these items but they must come back on during a power failure regardless of any switches you add.

I think the easiest way to deal with this is to use a relay listed for that purpose. Here is one but many manufactures make them.

http://www.wattstopper.com/products/lighting-control-panel-systems/emergency-lighting-control/elcu-200.aspx#.U5TsEXZhsTA

Is there no requirement that the exit lights stay go on automatically when there are people in the building? I have never seen an exit light on a switch per se.
 

fmtjfw

Senior Member
NO. NO. NO.

NO. NO. NO.

My employer has asked to install an emergency lighting system in our facility. My immediate boss has asked me to to install a switch for each exit sign and emergency light,, however I am thinking that switching is not allowed for an emergency lighting system. Is switching allowed in an emergency lighting system?
If you are using emergency lighting and/or exit signs with built-in battery backup, turning the normal power off will cause them to go on -- using the batteries. Turning them off each night will eat the batteries really quickly. -- Economic argument.

Life Safety NFPA 101 (2009 ed) 7.9.2.1* Emergency illumination shall be provided for a minimum of 1? hours in the event of failure of normal lighting.

If the emergency lighting fixture has discharged the battery overnight, how are you going to meet the 1? hour rule when they are first turned on in the morning? -- you can't. -- Violate code requirements argument.

7.9.2.3* The emergency lighting system shall be arranged to provide the required illumination automatically in the event of the interruption of any operation of the normal lighting due to any of the following:

(1) Failure of a public utility or other outside electrical power supply
(2) Opening of a circuit breaker or fuse
(3) Manual act(s), including accidental opening of a switch controlling normal lighting facilities

Battery-backed-up fixtures have no wiring provision to turn off the light without turning off the battery charger. Modifying them to do so would violate their listing. I for one would avoid violating the listing of a "Life Safety" device or installing them contrary to their instruction sheets or listing. I'm fairly certain putting them on a switched circuit would be such a violation. [This may not apply to emergency battery-backed-up ballasts?]

Battery backed up exit signs typically now use LEDs -- electrical power is very minimal. Same argument as emergency lighting above.

Somebody needs to talk to the local fire department or fire marshal before implementing such a hair-brained scheme.
 
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iwire

Moderator
Staff member
Location
Massachusetts
If you are using emergency lighting and/or exit signs with built-in battery backup, turning the normal power off will cause them to go on -- using the batteries. Turning them off each night will eat the batteries really quickly. -- Economic argument.
True, if the emergency lighting is battery powered and if you kill the power to the charger that is a problem. An obvious one, one that I assume any electrician would know.


Battery-backed-up fixtures have no wiring provision to turn off the light without turning off the battery charger.
Some do not but many battery backed up fixtures actually have a specific connection for control of the light without killing the charger circuit.

But more importantly many buildings do not use battery back up, they use a generator.

Somebody needs to talk to the local fire department or fire marshal before implementing such a hair-brained scheme.
I suggest you need to be exposed to more standard methods before calling things hair brained.

Switch controlled emergency lighting fixtures are very common in buildings that use emergency ballasts or have emergency generators. Many retail stores shut down all egress lighting when the space is unoccupied. Sometimes this includes exit signs.

Again, this is perfectly legal if arranged to come on automatically if there is a power failure.
 

fmtjfw

Senior Member
True, if the emergency lighting is battery powered and if you kill the power to the charger that is a problem. An obvious one, one that I assume any electrician would know.

Some do not but many battery backed up fixtures actually have a specific connection for control of the light without killing the charger circuit.

But more importantly many buildings do not use battery back up, they use a generator.

I suggest you need to be exposed to more standard methods before calling things hair brained.

Switch controlled emergency lighting fixtures are very common in buildings that use emergency ballasts or have emergency generators. Many retail stores shut down all egress lighting when the space is unoccupied. Sometimes this includes exit signs.

Again, this is perfectly legal if arranged to come on automatically if there is a power failure.
OK, I am not familiar with battery-backed systems with a separate switch to turn off the light and still power the charger. I apply the KISS principle when it comes to life safety. The more stuff you have that can make the lighting not come on the less safe it is.

Again this is a single posting from the OP with no further detail.

The simplest way to ADD emergency lighting and lighted exit signs to a facility is to use simple battery backed up packs with batteries and lights as a unit. To add exit signs is to use the packs with attached exit signs. If you labor costs anything, it is probably also the cheapest. [Hang the pack, tap into the power feed for the area lighting, done.]

There is the more complicated problem of knowing where to put the lighting and the exit directional signs, accounting for the proper footcandles, and accounting for a single failure while still maintaining lighting levels.

If you are using a low voltage central battery, you have to contend with voltage drop problems in the circuits and the zillion relays to detect local power failures [if they still install such systems.] If you use remote heads with small battery packs you still have to look out for voltage drop.

If they already have an emergency generator one would be very surprised that emergency lighting was not already provisioned.

But on the otherhand I guess I was positive in my statements (Wrong at the top of my voice).
 

iwire

Moderator
Staff member
Location
Massachusetts
OK, I am not familiar with battery-backed systems with a separate switch to turn off the light and still power the charger.
In my area it is very popular option to have battery units installed inside the wiring compartments of standard lighting fixtures. You can get these UL life safety battery units for LED, Flouresent and HID fixtures. Here is some info from one maker

http://www.bodine.com

These units require a 24/7 feed for the battery but have a lead for switching the lamps on and off.

I apply the KISS principle when it comes to life safety.
Rock and roll all night and party every day?



Kidding, I understand the principle. :)


The more stuff you have that can make the lighting not come on the less safe it is.
No doubt, but at the same time sometimes the fixtures used for emergency lighting are the same ones used for general lighting in stores, schools, offices etc. so being able to turn them off is in my opinion a good reason to add some stuff.

Check out these

http://www.functionaldevices.com/lighting-controls/ul924.php

http://www.hubbell-automation.com/products/bypass_relays/

http://www.wattstopper.com/products/lighting-control-panel-systems/emergency-lighting-control/elcu-200.aspx#.U5XbaHZhsTA


Again this is a single posting from the OP with no further detail.
That is a good point, in our own minds we look at it from our own experiences and tend to assume that the OP was doing the same type of work we do.

The simplest way to ADD emergency lighting and lighted exit signs to a facility is to use simple battery backed up packs with batteries and lights as a unit. To add exit signs is to use the packs with attached exit signs. If you labor costs anything, it is probably also the cheapest. [Hang the pack, tap into the power feed for the area lighting, done.]
I agree that is the simplest and cheapest way but this is where I applied the KISS principle. I just assumed no qualified person would be asking about switching off the feed to an emergency battery pack. That could be a mistake of mine. :)


There is the more complicated problem of knowing where to put the lighting and the exit directional signs, accounting for the proper footcandles, and accounting for a single failure while still maintaining lighting levels.
In my experience almost no one voluntarily decides to add emergency lighting, they have usually been directed to add emergency lighting and / or Exit signs in spots X, Y and Z by an inspection official. YMMV.


If you are using a low voltage central battery, you have to contend with voltage drop problems in the circuits and the zillion relays to detect local power failures [if they still install such systems.] If you use remote heads with small battery packs you still have to look out for voltage drop.
The last central battery unit I put in that operated at 12 volts was in 1984, as you say voltage drop is an issue. Now we are installing central battery units that have inverters on board that allow us to distribute at 120, 208, 277 480 etc. Some of them are large

http://www.dual-lite.com/products/trident_trn_series/?pbid=405323

This overcomes voltage drop issues but it is installed just like a generator system, all circuits must be run independently of other circuits. Its an expensive installation but an option if the project cannot use a generator for some reason.


If they already have an emergency generator one would be very surprised that emergency lighting was not already provisioned.
I still find inspectors such as fire officials asking for more at yearly inspections. Particularly if the lay out of a room has changed or its an old building that they want to bring up to modern standards without hurting the owner with too much work at once.

It will be interesting to here from the OP.
 
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