Job, to fit a 5 inter-linked smoke alarms. In the install guide (see TLC tec section) they quote that 3 core T+E should be used to power and inter-link alarms from a single power source. However in a large building, at lease one of the alarms must be wired through conduit outside, the conduit is shared with other ELV cables (data/tel) etc. And alarms will be located in areas not powered from the same CU on sub-mains. What I wanted to do was wire the power for each alarm from the local lighting circ (reg used, alarms bat backup) and then use red (if I can get instead of brown!) 1.0mm single and run this between each of the inter-connect terminals. Any ideas if this might work?? Thanks.
If it did work - do you hink it would be safe, especially considering that you might not be the only person ever to open up one of these smoke alarms? Try Aico radio-link bases, expensive but brilliant.
it will work as the third core is only used as a "switch". the different phases wont make a difference but if cant run the power for the smokes in with elv circutits. it will induce a voltage on the other cables
If your building is that big are you sure you don't need a full blown fire alarm system. I'd have a word with the local building control before I quoted.
it all depends on if the interlink wire is neutral relative or earth realative if its earth relative you should be ok using a single and earth cable but frankly i agree if it's big enough to be considering this sort of thing its probablly big enough to reqire a proper alwarm system finally if you do wan't to run a full interlinked alarm cuircuit outside you could use a 3 core (or 4 core if you wan't to use a core for earth) swa
I have a feeling that you should have a fire alarm circuit seperate and clear of any other utilities,not in the same conduit.
Basically its one building, though the extension is on a sub-main. The reason conduit is needed, is because it is not possible to chase a cable into the wall or go under floor etc for the new rooms with a peaked roof, so the cable is routed outside between two lofts. A full fire alarm is a bit OTT, even the fire co who check the extinguishers said it probs wasn't necessary. So its really a question, if something along these lines can be setup, or if basic alarms are used instead, which are far from providing a decent level of protection. The RF bases are a good idea, but well above budget. Would the interlinked core carry power 24/7? I'd imagine only during alarm. The ELV is CAT5 so shouldn't induce anything into the single core, however if the core was powered it could induce into the CAT5. Also, if 3core T+E was used voltage drop would start to be an issue.
If the devices have a backup power supply, they can be installed on a local lighting circuit. Read B1 Sec 1.17 of Building Regs as regards power supplies for Smoke Alarms: Click Here Also gives document gives details of requirements for different types and uses of buildings.
Would the interlinked core carry power 24/7? I'd imagine only during alarm. Stop imagining things and find out. Take 2 out of the boxes, wire them up, connect a voltmeter to the link terminals, and set one off with a smouldering rag.
quite likely are you aware what it is realtive to? if it is earth relative then it should be possible to run it between alarms on different cuircuits/phases without problems i think there is a need to experiment here try connecting two interlinked alarms with no earth to one of them and see if the interlink still works
Take 2 out of the boxes, wire them up, connect a voltmeter to the link terminals, and set one off with a smouldering rag. Best just use the test button, in case you burn the place down.
Now that would be ironic! If the test button also tests the interlink function, and sets off the other alarms, then yes, this would probably be better.
Sounds to me as though a good read of BS5839 Pt 1 & Pt 6 would be a good idea and then maybe a chat with local building control.
there is a smoke alarm on the market Aco i think with a radio link base this would suit your requirment
there is a smoke alarm on the market Aco i think with a radio link base this would suit your requirment Read the topic - he said they are too expensive..........
BAS if you ever wired up smoke alarms you would know that when you try one test button that the others should also sound, basic building control regs, so stop being so dogmatic and condescending to people and put your brain into gear before opening your trap.
Blimey - WTF rattled your cage? The question was "Would the interlinked core carry power 24/7? I'd imagine only during alarm", so I suggested wiring a couple up, and finding out. Minesa Pint pointed out that using the test button would be a better method than the one I'd suggested, and I said that if it would exercise the link then it would be better. Where on earth do you get your "dogmatic and condescending" from?