emergency lighting
- Thread starter ajengin
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luke warmwater
Senior Member
Re: emergency lighting
2 lights in each room, or just 2 lights??
There are numerous ways to do this.
One way would be to seperate the 2 lights on to their own switch.
Another would be to pull a seperate circut for the 2 lights, and use a double pole switch.
There are just so many options that it is impossible to give you a 'best' answer.
You have provided way too little information, and so it would probably need an 'on site' evaluation.
2 lights in each room, or just 2 lights??
There are numerous ways to do this.
One way would be to seperate the 2 lights on to their own switch.
Another would be to pull a seperate circut for the 2 lights, and use a double pole switch.
There are just so many options that it is impossible to give you a 'best' answer.
You have provided way too little information, and so it would probably need an 'on site' evaluation.
Re: emergency lighting
2 lights out of the 8 in each room. We considered separating them on a separate switch but if the switch is not in the on position then it would never provide emergency illumination.
The double pole switch is an excellent option.
I am basically trying to see if there any other design ideas that are better.
2 lights out of the 8 in each room. We considered separating them on a separate switch but if the switch is not in the on position then it would never provide emergency illumination.
The double pole switch is an excellent option.
I am basically trying to see if there any other design ideas that are better.
Re: emergency lighting
Becareful of system wiring seperation. If the "Emergency" circuits are indeed "Emergency" per article 700.1, you will have to comply with 700.9(B), if these circuits are simply "Legally Required" per 701.2, they can occupy the same raceways and boxes as "General" wiring circuits per 701.10.
If they fall under 702 they can also share raceways and boxes, see 702.9
Roger
Becareful of system wiring seperation. If the "Emergency" circuits are indeed "Emergency" per article 700.1, you will have to comply with 700.9(B), if these circuits are simply "Legally Required" per 701.2, they can occupy the same raceways and boxes as "General" wiring circuits per 701.10.
If they fall under 702 they can also share raceways and boxes, see 702.9
Roger
Re: emergency lighting
"Lighting Control and Design" makes a GR2400 relay that will bypass the off switch during a power failure.
One other option is to leave the emergency lights on 24/7 (cheapest initial option, but not the best for energy conservation).
Steve
"Lighting Control and Design" makes a GR2400 relay that will bypass the off switch during a power failure.
One other option is to leave the emergency lights on 24/7 (cheapest initial option, but not the best for energy conservation).
Steve
- Location
- Massachusetts
Re: emergency lighting
If the these lights are part of the required emergency egress lighting you may not switch them off unless arraigned to come on in the event of a power failure.
This is usually accomplished with normally closed relays or contactors.
However it sounds like this person wants the lights for convenience. This being the case these lights should not be added to any Article 700 emergency system. They could be powered by an article 702 optional standby system. If they are optional they can be switched anyway you want.
Emergency power systems can only power required emergency loads.
Standby power systems can power whatever you want that is not required to be powered by emergency systems.
Edit; I was typing while the others where posting, at least we are all have the same thoughts.
[ April 22, 2005, 11:26 AM: Message edited by: iwire ]
If the these lights are part of the required emergency egress lighting you may not switch them off unless arraigned to come on in the event of a power failure.
This is usually accomplished with normally closed relays or contactors.
However it sounds like this person wants the lights for convenience. This being the case these lights should not be added to any Article 700 emergency system. They could be powered by an article 702 optional standby system. If they are optional they can be switched anyway you want.
Emergency power systems can only power required emergency loads.
Standby power systems can power whatever you want that is not required to be powered by emergency systems.
Edit; I was typing while the others where posting, at least we are all have the same thoughts.
[ April 22, 2005, 11:26 AM: Message edited by: iwire ]
Re: emergency lighting
thanks guys...it seems that we are going to use this for emergency luminaires, So i can follow 700.9B...where it states that I can mix wiring.
What I don't understand how would we use two sources in one junction box?
Sometimes i feel like i need a law degree to decipher the NEC or it might be my inexperience.
thanks guys...it seems that we are going to use this for emergency luminaires, So i can follow 700.9B...where it states that I can mix wiring.
What I don't understand how would we use two sources in one junction box?
Sometimes i feel like i need a law degree to decipher the NEC or it might be my inexperience.
- Location
- Massachusetts
Re: emergency lighting
Remember this is life safety equipment the rules are strict and should be followed or you can be in a world of trouble if a failure is traced to the added equipment.
As far as mixing the two sources as an example you might feed one ballast in a fixture with 'normal' power and the other ballast in the fixture with 'emergency' power.
Many times the engineers try hard to keep the load on the emergency systems as low as possible in order to keep the generator reasonably sized.
They are only emergency Luminaires if they are required by building codes to be installed for egress lighting. Any other lights fall under optional systems and can not be added onto the emergency systems.
Remember this is life safety equipment the rules are strict and should be followed or you can be in a world of trouble if a failure is traced to the added equipment.
As far as mixing the two sources as an example you might feed one ballast in a fixture with 'normal' power and the other ballast in the fixture with 'emergency' power.
Many times the engineers try hard to keep the load on the emergency systems as low as possible in order to keep the generator reasonably sized.
ryan_618
Senior Member
- Location
- Salt Lake City, Utah
Re: emergency lighting
Even worse than 700.9 would be 700.6(A), which would require a signifigant amount of work, most likely.
Even worse than 700.9 would be 700.6(A), which would require a signifigant amount of work, most likely.
Re: emergency lighting
No, per the wording, you will not be able to share a switch or the box. (the box can be shared if you install a barrier to seperate the systems)
I think there should be some additional allowances in 700.9(B) for situations such as this one.
Roger
[ April 22, 2005, 02:37 PM: Message edited by: roger ]
No, per the wording, you will not be able to share a switch or the box. (the box can be shared if you install a barrier to seperate the systems)
I think there should be some additional allowances in 700.9(B) for situations such as this one.
Roger
[ April 22, 2005, 02:37 PM: Message edited by: roger ]
coppertreeelectric
Senior Member
Re: emergency lighting
Just a question out of curiosity: Why not just install emergency light wall packs, or install fixtures that have back-up battery supplies that work during normal operation but kick in on battery when the primary power drops?
Steve
Just a question out of curiosity: Why not just install emergency light wall packs, or install fixtures that have back-up battery supplies that work during normal operation but kick in on battery when the primary power drops?
Steve
coppertreeelectric
Senior Member
Re: emergency lighting
In this case why not use a auto transfer switch where you place the emergency ckts on the transfer switch, then when the power cuts the select ckts will be on the generator? I have done this several times for my cities fire department.
All you have to do is move the select ckts over to the transfer switched breaker box and the switch does all the work for you. Most office lighting ckts dont draw much amperage so why not keep all the necessary lighting on the transfer switch?
Your 100% right. I was thinking more along the lines of emergency evacuation, not emergency power working conditions.
In this case why not use a auto transfer switch where you place the emergency ckts on the transfer switch, then when the power cuts the select ckts will be on the generator? I have done this several times for my cities fire department.
All you have to do is move the select ckts over to the transfer switched breaker box and the switch does all the work for you. Most office lighting ckts dont draw much amperage so why not keep all the necessary lighting on the transfer switch?
Re: emergency lighting
The relay I mentioned fits in a 2 gang box, and has a built in divider so emergency and normal power is kept separate. It is "ETL tested to UL listings" whatever that means.
Steve
Coppertree: Placing the light on a transfer switch still doesn't do anything for local switching.
P.S. Can I get some seeds off your Coppertree? I would like to grow some too!!
The relay I mentioned fits in a 2 gang box, and has a built in divider so emergency and normal power is kept separate. It is "ETL tested to UL listings" whatever that means.
Steve
Coppertree: Placing the light on a transfer switch still doesn't do anything for local switching.
P.S. Can I get some seeds off your Coppertree? I would like to grow some too!!
coppertreeelectric
Senior Member
Re: emergency lighting
It would do something for the local switching if all of the lighting in question was on the transfer swith.
The seeds come from a far away land and cost me to much money to just offer them to the public. I am sorry but I must keep them a corporate secret.
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