Alarm installation

[Andy™]

had an an alarm panel/bell to replace today. old alarm falling off wall, fairly old, and no use. wiring inside alarm was very good, all cores twisted, well marked what cable was what etc, generally a good install. then the bad point. there was no power supply to it. followed the flex back and found it was doubled up into a 5A round pin socket in the cupboard...

... this 5A socket is the switched supply for heating pump. i have no idea what he was thinking when he connected flex to there...

ended up adding FCU next to socket on other side of wall

 

[elvis]

They're v. good some of these guys! Alarm installer, prob knows his job v. well but not so up to scratch with the actual electrical part of it.

It's one job I've never done and always meant to look a bit more into it. Made minor repairs to a few and been asked a few times and always said no. The vaunted Professional Electrican magazine ran a series of articles on it a few months back but missed a couple of issues... know the thoery and that they should be quite simple but just always passed me by.

 

[Andy™]

i have no problem installing domestic alarms. just as long as its not red-care etc. there isnt really much to it

and slightly OT, but why has alarm cable not been harmonised to brown, black, grey, dark grey, light black etc yet?!

 

[Barx]

because its elv

 

[Barx]

Btw I've fitted hundreds of systems, was an alarm engineer for 6 years. Piece it pish really. Only hard bit is getting cable in without damage, etc. Comes with practice though.

 

[elvis]

That's always what I thought, drilling door frames etc.

Do you have a general practice of wiring all of your cable in a physical loop or do you wire them all back to the box and join them in there? Or (again) does this change from job to job?

 

[Andy™]

Most alarms i install (from scratch) are done with a re-wire, so wiring has easy access to under floors etc. normally, i have 1 cable from panel per zone. and normally 1 detector per zone. sometimes use one cable for more than one zone if they are close to each other

alarm replacements can be wired any way, some on own cables, some sharing etc

 

[Barx]

Should never wire an alarm in a 'loop'. Each device has its own run back to the panel. Though larger system are a little different but never a loop.

 

[Barx]

Most alarms i install (from scratch) are done with a re-wire, so wiring has easy access to under floors etc. normally, i have 1 cable from panel per zone. and normally 1 detector per zone. sometimes use one cable for more than one zone if they are close to each otheralarm replacements can be wired any way, some on own cables, some sharing etc

Many systems get installed with pirs sharing cables...They shouldn't.

Powered devices should be on their own. None powered can share though its typically avoided in the trade.

 

[Andy™]

Many systems get installed with pirs sharing cables...They shouldn't.

dont really see the problem with it. each PIR still has its own zone at the panel

 

[Barx]

its 1 of them regs things mate. 99.9% of time they are ok. Evry now and again 1 will suffer from volt drop, etc

 

[elvis]

So what about window/door magnets, they are all wired individually back to the panel? Was always under the impression they were wired in a loop...

 

[Barx]

If sharing a zone (which you could as they are none powered devices) then you could run panel - 1 contact - 2 contact- etc. Then conect zone through in 1 big 'alarm loop'. i see what ya was getting at now

 

[Andy™]

So what about window/door magnets, they are all wired individually back to the panel? Was always under the impression they were wired in a loop...

alarms work on a closed circuit, so if more than one detector, it would be wired in series /loop

 

[Andy™]

its 1 of them regs things mate. 99.9% of time they are ok. Evry now and again 1 will suffer from volt drop, etc

never had a problem with this in domestic (but then cable runs are fairly short compared to commercial systems)

 

[green-hornet]

I always try to wire 1 trigger 1 zone, much easier to program for double knock or latching.I use veritas for domestic and small commercial uses but I have been impressed with the new ranges for larger premises.

Again I think alarms are always going to be what you are used to fitting and comfy with.

 

[Jono Pashley]

Are there any good courses on Security/Fire Alarm installation? Might be something for me to look into over the summer.

 

[green-hornet]

Depends how far you wish to go, and what type of work you wish to follow.

All certificates for any installation require a level of competancy, this can be proved by past experiance or relevant qualifications.

To do alarms of any kind you must be in possession of the relevant regulation books just like any other regulation.

http://www.niceic.com//en/contractor/article.asp?SECTION=26&ARTICLE=22&VIEW=26&GROUP=Commercial+%26+Industrial&COURSE=Fire+Alarm+And+Emergency+Lighting||13&source=google&kw=fire%20alarm%20training&cmp=training&gclid=CIHjvZKKoZkCFQ00QwodSmZWpw

 

[bassman]

Many systems get installed with pirs sharing cables...They shouldn't.Powered devices should be on their own. None powered can share though its typically avoided in the trade.

Domestic systems can be wired via one cable 8 core or 12 core to loft as usually you are only using the power from the control unit,these are more and more being fitted in the loft and all cabling going to the protection from there,as you have a remote keypad now.

Individual indication on the control s or a means of idintifying which zone has activated.

I have been asked to look at some due to problems and they have been fitted by people who think it is easy Pir's looking at windows fantastick for activating on sunny days.

must admit it is not difficult but a bit of care and common sense is required.

Have seen and worked on large installations Tube and Wired frames window, foil.ir beams

many hours spent on call had to put mains through the wireing to find or cure a fault as the meggar wouldnt fix it.

 

[elvis]

Then conect zone through in 1 big 'alarm loop'. i see what ya was getting at now

Phew... was feelin a bit thick till you said that!!

So let me get this straight - an example:

I wire a series loop for magnets downstairs - Zone 1

As above upstairs - Zone 2

And an individual cable to each sensor - Zone each

Yes??

Biggup comin to you and AndyC... if and when I take one on I'll give 10% to 'the best and friendliest electrician forum on the web' - minus materials of course Blushing