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FIRE SERVICE AND GENERAL FIRE SAFETY TOPICS => Technical Advice => Topic started by: Benzerari on August 31, 2008, 10:40:48 PM
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Guys;
What prevent of designing and manufacturing a conventional fire alarm system with loop circuits rather than radial circuits, no EOL any more.
Would that be a good addition to the old limited technology (as it still beneficial to some small applications) or this would be just like running backward?
Thank you
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As a conventional system operates 1 zone per cable, then this could potentially double up on cable required surely? As for example Zone 4 (say 3rd floor for example) cable would then have to come back to the panel.
In principle a good idea as a cable break wouldnt necessarily affect a large majority of the zone if near the begining of the zone, but more and more systems are going down the analogue addressable route now anyways due to the huge price reduction in the equipment
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Benz ,
Short answer - none look at the way the intruder game has gone with equipment , I for one dont want my customers that they can a panel for £30.
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Thank you both for your comments, any more technical opinions are welcome, we learn from criticism :)
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Guys;
What prevent of designing and manufacturing a conventional fire alarm system with loop circuits rather than radial circuits, no EOL any more.
Would that be a good addition to the old limited technology (as it still beneficial to some small applications) or this would be just like running backward?
Thank you
Benz,you would give a paracetemol a headache sometimes!!!I can see the benefit of having a ring circuit as opposed to a radial for a conventional system with regards to keeping the system "fed" from both ends,but it falls down on a couple of points (at least).
Firstly,unlike an addressable system,there would be difficulty tracing an open circuit because you couldn't get a print out to show where in the loop the break was (ie - between device 30 and 31 say).
Secondly,because a zone is restricted to 2000m2 then a conventional zone circuit can only cover this area.On the cost side you are increasing the cabling required per zone which is a major factor - weighing up the cost of conventional/addressable equipment over cable costs then the difference in the cost of detectors on a flat 2000m2 ceiling would be around £300/£400 between conventional and addressable per zone.
The two-wire systems offer the benefit of an addressable system (sounders and interfaces on the same circuit as the detection) but keep the installation costs down by using a radial circuit.
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Guys;
What prevent of designing and manufacturing a conventional fire alarm system with loop circuits rather than radial circuits, no EOL any more.
Would that be a good addition to the old limited technology (as it still beneficial to some small applications) or this would be just like running backward?
Thank you
Surely saving the cost of an EOL device but adding the cost of extra cabling cannot be advantageous in any way? You would still have the cost of the 'loop' monitoring circuitry in the panel so it really would be just saving the cost of an EOL.
With reference to the benefits of addressable systems highlighted in other posts please also remember that these benefits can be brought to older systems because BS5839 part 1 2002 allows you to use addressable systems on two-wires, if that two wire circuit doesn't extend over an area of more than 2000m2, so it is quite possible to convert an old non-addressable zonal system to addressable and retain the old wiring (as long as it is in good enough condition)
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Benz,you would give a paracetemol a headache sometimes!!!
Did you get any complains from paracetamol Buzz ? if yes it should be out of date then! :)
I can see the benefit of having a ring circuit as opposed to a radial for a conventional system with regards to keeping the system "fed" from both ends,but it falls down on a couple of points (at least).
Firstly,unlike an addressable system,there would be difficulty tracing an open circuit because you couldn't get a print out to show where in the loop the break was (ie - between device 30 and 31 say).
Secondly,because a zone is restricted to 2000m2 then a conventional zone circuit can only cover this area.On the cost side you are increasing the cabling required per zone which is a major factor - weighing up the cost of conventional/addressable equipment over cable costs then the difference in the cost of detectors on a flat 2000m2 ceiling would be around £300/£400 between conventional and addressable per zone.
The two-wire systems offer the benefit of an addressable system (sounders and interfaces on the same circuit as the detection) but keep the installation costs down by using a radial circuit.
Thank you for this technical adds :)
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Guys;
What prevent of designing and manufacturing a conventional fire alarm system with loop circuits rather than radial circuits, no EOL any more.
Would that be a good addition to the old limited technology (as it still beneficial to some small applications) or this would be just like running backward?
Thank you
Surely saving the cost of an EOL device but adding the cost of extra cabling cannot be advantageous in any way? You would still have the cost of the 'loop' monitoring circuitry in the panel so it really would be just saving the cost of an EOL.
With reference to the benefits of addressable systems highlighted in other posts please also remember that these benefits can be brought to older systems because BS5839 part 1 2002 allows you to use addressable systems on two-wires, if that two wire circuit doesn't extend over an area of more than 2000m2, so it is quite possible to convert an old non-addressable zonal system to addressable and retain the old wiring (as long as it is in good enough condition)
Cheers, for this technical add wiz
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Benz ,
I have changed my mind , I love the idea , no end of lines , think of the trouble you save yourself .....
re: bell splitter thread .
Buzz , where are the Paracetamols ?
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i took them all a long time ago....
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Guys;
What prevent of designing and manufacturing a conventional fire alarm system with loop circuits rather than radial circuits, no EOL any more.
Would that be a good addition to the old limited technology (as it still beneficial to some small applications) or this would be just like running backward?
Thank you
pointless deisgning a non addressable system with this technology.
Twin wire systems brigde the gap between basic and a/a.
the basic is still a good cost effective solution to very small installs.
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Benz ,
I have changed my mind, I love the idea, no end of lines, think of the trouble you save yourself .....
Never mind, you don't need to rush, there is plenty of time, to think and re-think again :)
re: bell splitter thread .
I haven't understood what the problem of that thread is :)
Buzz , where are the Paracetamols ?
In the chemist mate :), also there is a made in China one, 1/10 of the right price, would you be interested, order it from e-bay :)
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Guys;
What prevent of designing and manufacturing a conventional fire alarm system with loop circuits rather than radial circuits, no EOL any more.
Would that be a good addition to the old limited technology (as it still beneficial to some small applications) or this would be just like running backward?
Thank you
pointless deisgning a non addressable system with this technology.
Twin wire systems brigde the gap between basic and a/a.
the basic is still a good cost effective solution to very small installs.
Easy; to say 'pointless...' Grame, I want you to point out any technical benefits and/or disadvantages, like others did, we are discussing in a technical way, and there is no knife around the neck, to force who ever to accept or reject :)
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i took them all a long time ago....
Is that because of the incoming recession? Half the world is in recession, not only us! :D