Wireless heat and smoke alarm

[deuce22]

Hi.

I need to fit a Wireless heat and smoke alarm.

The electrician has spurred off a light fitting in the kitchen and one in the hall, but I have just checked and it is twin and earth cable.

Can the still be connected with twin and earth or does it have to be 3 core and earth.

Thanks.

 

[SaladFingers]

It's wireless.

Can you think of what the third core would be needed for?

 

[securespark]

If it's wireless, does it need a mains supply at all?

 

[deuce22]

They are linked wirelessly, so if one goes off, it alerts the other one to go off. It still needs to be connected to the mains.

I thought that you would need 3 core + earth if they weren't wireless, so one of the cores would send the signal to the other unit.

I'm buying a set from an online company and the image shows 3 core + earth. I spoke with someone and they said that I do need it. Not sure though if they are correct.

Cheers.

 

[SaladFingers]

They are linked wirelessly, so if one goes off, it alerts the other one to go off. It still needs to be connected to the mains.

I thought that you would need 3 core + earth if they weren't wireless, so one of the cores would send the signal to the other unit.

I'm buying a set from an online company and the image shows 3 core + earth. I spoke with someone and they said that I do need it. Not sure though if they are correct.

Cheers.

Right, ok, I thought my first post would point you in the right direction.

Connected to the mains, two cores plus earth. The link is wireless.

Only if they are not wireless, would they need the third core for the link.

What has this electrician spurred off to? So did he not fit the alarms?

If twin and earth, then that's fine for wireless link alarms.[/b]

 

[rjm2k]

Maybe the 3rd is for direct link if the wireless has issues due to interference? What do the instructions say the 3rd is for?

 

[SaladFingers]

Maybe the 3rd is for direct link if the wireless has issues due to interference? What do the instructions say the 3rd is for?

Excellent idea, fantastic. Genius.

My wireless internet has cables just incase of wireless failure.

 

[rjm2k]

Maybe the 3rd is for direct link if the wireless has issues due to interference? What do the instructions say the 3rd is for?

Excellent idea, fantastic. Genius.

My wireless internet has cables just incase of wireless failure.

Don't know if you are taking the Part P or not there, it was just a guess and I would assume the instructions would make it clear. Since they presumably use the same frequency range as many other devices and are also affected by building structure, a direct connection may be needed in some instances?

I'm assuming your wireless internet isn't "safety critical" and peoples lives don't depend on it working?

What is it for then?

 

[SaladFingers]

Maybe the 3rd is for direct link if the wireless has issues due to interference? What do the instructions say the 3rd is for?

Excellent idea, fantastic. Genius.

My wireless internet has cables just incase of wireless failure.

Don't know if you are taking the Part P or not there, it was just a guess and I would assume the instructions would make it clear. Since they presumably use the same frequency range as many other devices and are also affected by building structure, a direct connection may be needed in some instances?

I'm assuming your wireless internet isn't "safety critical" and peoples lives don't depend on it working?

What is it for then?

dear lord.

Wireless alarms don't have a link for back up, that would render wireless useless.

The mains is backed up by a battery in each unit.

 

[rjm2k]

Maybe the 3rd is for direct link if the wireless has issues due to interference? What do the instructions say the 3rd is for?

Excellent idea, fantastic. Genius.

My wireless internet has cables just incase of wireless failure.

Don't know if you are taking the Part P or not there, it was just a guess and I would assume the instructions would make it clear. Since they presumably use the same frequency range as many other devices and are also affected by building structure, a direct connection may be needed in some instances?

I'm assuming your wireless internet isn't "safety critical" and peoples lives don't depend on it working?

What is it for then?

dear lord.

Wireless alarms don't have a link for back up, that would render wireless useless.

The mains is backed up by a battery in each unit.

But some wireless can be interconnected with non-wireless using a ... wire

 

[SaladFingers]

Maybe the 3rd is for direct link if the wireless has issues due to interference? What do the instructions say the 3rd is for?

Excellent idea, fantastic. Genius.

My wireless internet has cables just incase of wireless failure.

Don't know if you are taking the Part P or not there, it was just a guess and I would assume the instructions would make it clear. Since they presumably use the same frequency range as many other devices and are also affected by building structure, a direct connection may be needed in some instances?

I'm assuming your wireless internet isn't "safety critical" and peoples lives don't depend on it working?

What is it for then?

dear lord.

Wireless alarms don't have a link for back up, that would render wireless useless.

The mains is backed up by a battery in each unit.

But some wireless can be interconnected with non-wireless using a ... wire

....non wireless

 

[deuce22]

The electrician did some work in the house and left the cables their ready for when I fitted the alarms.

I haven't got the alarms yet, they are being delivered soon, so can't see the instructions.

I've just checked and the cables hanging down are spurred off completely different lights, so they are not even going to be connected via the same cable.

I'm now thinking that they do connect using twin and earth, because the electrician new that I had to use wireless alarms and I can't see him making a mistake.

I'll wait until they turn up and take a look at the instructions.

Cheers.

 

[SaladFingers]

I've just checked and the cables hanging down are spurred off completely different lights, so they are not even going to be connected via the same cable.

They won't be, as they'll be in completly different rooms.

I'm now thinking that they do connect using twin and earth, because the electrician new that I had to use wireless alarms and I can't see him making a mistake.

I'll wait until they turn up and take a look at the instructions.

Cheers.

They're wireless, they don't need three core.

 

[pjcomp]

Maybe it's because we're electricians some of us have problems thinking in terms of "without wire".

The whole point of a wireless system is to avoid lifting floorboards and running cables everywhere. If it's new build or a full refurb and the walls and floors are open then fine, run in the 3-and-earth between the detector points.

If it's retro-fitting to somewhere that's all decorated up, the wireless option saves a lot of work and mess.

You run a 2-and-earth feed to each detector (to power it), and then the wireless adaptor takes care of communication between the different detectors. The detectors still have a terminal for the link wire because they're standard detectors - the wireless transmitter/receiver is a bolt-on extra.

You can also combine wired and wireless links. For instance, house with wired connections between detectors; extension built on but impractical to extend the wired link. Add a wireless adaptor to one of the wired links, and put a wireless detector in the extension. Now the wireless and wired are integrated.

If you can get a wire between the detectors then they're linked and there's no need for the added expense of the wireless adaptor (they're around £40+ last time I looked).

PJ