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Fire/Smoke Alarm

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Wp100

Well-Known Member
Hi,

Have been installing some Texecom smoke alarms that connect up to the house burglar alarm and was looking to fit one to the external garage, but the manufacturer said it was not a good place, as the damp a wet car would bring in etc, would shorten the life of the circuit.

Thought about using a well sealed PIR unit, but think that will be prone to false alarms by a low east sun coming in from the windows, though suppose I could fit shades.

Had thought about a micro and temp sensor to sense a sudden large change.

Wondered if anyone had any better idea for a simple smoke /fire detector that will work in a sometimes damp area.

Thanks
 

chemelec

Well-Known Member
Probably one of the Kitchen Type Detectors would be better.
Not the Ionization Ones, But the ones that use a Light Beam & Detector to detect smoke.
They are Not Sensitive to Ionization and Not Quite as effective, but do work.
 

GromTag

Active Member
Not being much help, but what of a Carbon monoxide sensor? As it's in the garage. And as for the humidity is an all ways problematic issue with all electronics that are needed to not be sealed to detect smoke.
As the sensor chambers need to be exposed to detect smoke particles passing an ionization chamber of sorts, and CO2 detecting the air. CO2 can detect a fire by the offset in the atmosphere as well should be more acceptable as being mounted in the garage.

I had typed thoughts on the ideals, tho it was more towards rambling than providing useful info, mainly about issues with temp sensors needing to be in areas that would be effective/ time responsive, and PIR sees fire as flickering value on output. Tho I've never used a PIR.
Am aware that it can "see" heat as a thermal to value, then a controller works with that as per programming.

The PIR pointed towards key areas, such as a connected garage, towards the entry to the home per example to give warning for that area. Vehicle engine temperature when parked in garage may also cause some problems with an PIR seeing heat rise.

Tint on the windows would help as mentioned to prevent some ranges of false triggering.

And of coarse, I think you are clearly aware that a controller can trigger an out response to another system (household alarm) either a direct connect or an relay, Sealed Reed types often have good time on and can stand some heat in an room before quitting operation.
 

dr pepper

Well-Known Member
Most Helpful Member
In the workshop at work we often weld/grind and other smoke detector unfriendly activities, so we have a heat detector, you can buy them fairly easily.
There are 2 types of common smoke alarm, one uses americium, a radioactive source and a detector, maybe the source is sensitive to damp.
The other uses a photelectric sensor and a light path, I wouldnt have thought this type wouldnt be sensitive to damp, dust maybe.
Perhaps I'm missing something.
Security alarm connected smoke sensors are a very sensible thing to have in your home.
 
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