Wireless Smoke detectors

[m9441905]

Hi

Apols if this isn't the right forum!

I'm planning to fit some wireless smoke detectors to my elderly parents 4 bed 2 storey house. I know of one type of system, (made by EI?) which has a mains base station linked to detectors which are simply screwed to the ceiling in each of the other rooms. Apparently, there is a similar system which is completely wireless in the fact that the base can simply be screwed to the ceiling. Has anyone used this? Obviously, I'd prefer this type as it means I can install myself without having to find a local electrician.

If anyone has used such a system, can you let me know where I could buy it and any things I should be aware of when installing it such as the use of optical vs ionisation alarms and which type is best for which location?

Thanks for you help,

Maggie

 

[breezer]

since you are not installing it as a fire alarm, wire not use hard wired battery operated interlinked smoke detectors?

Much cheaper, no electrican required

Besides, good quality radi anything is not cheap.

I have seen one, each detector is also a sounder, novel when it stops as they stop one at a time, VERY expensive and needs a control panel too

 

[Job_n_knock]

Optical detectors literally look through the free air inside the chamber to a receiver and guage the amount of fine particles that make up "smoke" by detecting a less clearer view (in layman terms )

Ionisation detectors still do the same thing but differently. The sensing part of the detector consists of two chambers - an open, outer chamber and a semi-sealed reference chamber within. Mounted in the reference chamber is a low activity radioactive foil of Americium 241 which enables current to flow between the inner and outer chambers when the detector is powered up. As smoke enters the detector, particles become attached to the ions, causing a reduction in current flow in the outer chamber and hence an increase in voltage measured at the junction between the two chambers. The voltage increase is monitored by the electronic circuitry which triggers the detector into the alarm state at a preset threshold.
Battery smoke detectors are meant to be fit for purpose and should work fine so I agree... why not use those?

 

[m9441905]

Thanks for the responses! I would use standard battery ones but apparently the RF ones can be cancelled by a remote which would be a good idea for my rather arthritic mum as I don't want her having to climb up on chairs to cancel false alarms. Also, I need to interconnect as mum is a bit deaf as well and unlikely to hear an alarm going off downstairs.

If I were to use the standard battery ones, is it possible to interconnect without wiring to the mains, eg just wiring the alarms together, after screwing to the ceiling? If so I might consider this but would want to interconnect over two floors, so potentially need lots of wire (and cable clips!) to make a neat job of it.

I don't mind spending a bit of money on a good system, preferrably one I can fit myself as their local spark can be pretty hard to get hold of and may consider it too small a job to be worth his while. Any make that I should avoid?

Cheers,

Maggie

 

[breezer]

Optical detectors literally look through the free air inside the chamber to a receiver and guage the amount of fine particles that make up "smoke" by detecting a less clearer view (in layman terms )

Thats not quite true

in laymans terms you have a torch and an eye, neither can see the other.
when smoke enters the light is reflected off the smoke (or dust) particles and the eye sees the reflected light and so it activates.

m9441905

you can not wire "any old" smoke detectors together, you have to get interlinkable ones. but yes they do wire together with something as simple as bell wire, but alarm cable is better since each core is coloured (but you only need 2 cores)

good quality radio ones you are talking several K