UPS for Smoke Detectors - Residential

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Good evening. Lucas, TX building code follows IFC 2003, which calls for residential smoke detectors to be installed in accordance with NFPA 72. I have reviewed both documents.

In an attempt to reduce my time on a ladder replacing 9V batteries every six months, I want to install a central UPS at the fire control panel. The UPS would have a NIC (ntwk interface card) so that the UPS is cycled and calibrated on a monthly schedule.

Does anyone see anything in the code that I am overlooking or would prevent an installation of this nature?

Thanks, Jim
Too bad you're all the way in Texas. I'd be happy to take that job over, I charge $110/hr to walk around with a ladder and change 9V batteries :grin:
Thanks, you are affordable. I have spoken to the developer about this, and we can not find any reason that this can not be done and still be in adherence with both codes.
If you think about it, every time those 9V's start going bad is at 0200 hrs when you are in deep sleep. This solution is a good work around. V/R, Jim


Senior Member
NFPA 72-2007
11.6.2 Household Fire Alarm Systems.​
Power for household
fire alarm systems shall comply with the following requirements:
(1) Household fire alarm systems shall have two independent
power sources consisting of a primary source that uses
commercial light and power and a secondary source that

consists of a rechargeable battery.

I don't know if a UPS would be considered a rechargable battery that is listed for fire alarm use.


Senior Member
Thats a fail then - the key word here is 'independent'. One UPS isn't two independent power sources.


Senior Member
I thought U had to push the button any was... Check me here a UPS is what to a battery backup ... You going to sell some service contract on the UPS ? :grin: F/A is DC(witch'n) to me... :roll:

curt swartz

Electrical Contractor - San Jose, CA
I'm totally lost at what you are trying to do. If you have smoke detectors connected to a fire alarm panel the panel has battery backup and there are not batteries in the detectors. If you have standard AC/DC smoke alarms and want to supply them with a UPS you will still have batteries in the alarms to maintain.


Senior Member
Resi smoke detectors are not fire alarms. They are appliances.

A genuine resi fire alarm system should have an internal, rechargeable battery installed in the panel.


Senior Member
The smoke detector is UL rated to operate with a battery and has the ability to warn the home owner when the battery is in poor condition. How would the home owner know if the UPS was off line? I don't think this would be UL approved..
I am new to this forum, and I appreciate everyone's thoughts on this subject.

My plan was to ntwk the UPS so that I could condition it on a monthly cycle to maintain peak runtime in the event of a power failure.

I am going to contact the building inspectors to get their ruling on this and will post it accordingly on this forum.

Respectfully, Jim
A UPS would provide a good back up power supply, but they are also a bit more expensive than a 9 volt battery. Have you looked at 110VAC residential smoke detectors with a 10-year Lithium battery? This may not be the best option...


Senior Member
Removing the battery would also go against the manufacturers instructions? I know on mine there is tamper switch on the battery compartment and will beep if there is no battery installed.


Senior Member
so you are dealing with smoke alarms, not a smoke detector

How would adding a UPS solve this problem? The battery would still installed and would eventually go bad.

Forget all that, it is recommended (by the NFPA) to change the batteries every year. I assume the installation instructions would have a similar requirement. Get a maintenance contract to change the batterie$.

curt swartz

Electrical Contractor - San Jose, CA
If the purpose of this is to eliminate the 9 volt battery in standard smoke alarms I think the occupants would much rather replace the battery once a year instead of listening to the beeps every few minutes due to the missing battery. :)
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