Alarm installation

[elvis]

Sorry, biggup Bassman too!

 

[Andy™]

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 senson - 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

that would work, but if possibly, run each sensor on its own - easier to fault find later and part set/disable zones etc.

generally, a global tamper is everything, but with some panels, if you have room, you can use zones as tamper. i.e if you have a veritas and you have 4 sensors, you ca use zone 1-4 as sensors, and zone 5-8 as tamper

 

[elvis]

Now... the tamper... theres a thing.

I understand the tamper circuit but:

Why would you need four zones as a tamper? Do you just short out any left over zones as part of the tamper circuit??

 

[oliver1234]

There is no requirement to run a seperate cable to each detector as long as each detector is on it's own zone. It is very common in commercial and domestic installs to have a 12 core from the panel to the first detector then an 8 core from the first to the second etc. It all depends on how easy it is to run the cables.

New graded systems only require a 4 core to a pir, 2 for power and the other pair does the alarm and tamper using end of line resistors.

The Texecom Veritas R8+ is a cheap domestic panel but even this can be programmed for EOL wiring.

 

[Andy™]

Now... the tamper... theres a thing. I understand the tamper circuit but:

Why would you need four zones as a tamper? Do you just short out any left over zones as part of the tamper circuit??

you can have it as a global tamper, but if there is room, you can use the spare zones as the tamper.

i.e zone 1, PIR, tamper to zone 5

zone 2, PIR, tamper to zone 6

zone 3 to zone 7

zone 4 to zone 8

then if you do have a tamper fault, it narrows it down immediatly, rather than taking apart connectors in the panel to narrow it down to a zone/detector

 

[oliver1234]

But not all panels allow you to use a zone as a tamper, and unless the veritas has changed you can't do it with the Veritas. You can program a zone as 24 hour but it will still be a positive loop and does not comply with the standards when used as a tamper circuit. It will activate the alarm when unset and it will give you a zone indication but that's only half the story. The tamper loop should cause an alarm activation when it's shorted to a zone loop and using a zone will not achieve this.

 

[NozSpark]

you can have it as a global tamper, but if there is room, you can use the spare zones as the tamper.i.e zone 1, PIR, tamper to zone 5

zone 2, PIR, tamper to zone 6

zone 3 to zone 7

zone 4 to zone 8

then if you do have a tamper fault, it narrows it down immediatly, rather than taking apart connectors in the panel to narrow it down to a zone/detector

But then your tamper circuit would only be active when the panel is set, surely it should be active 24/7??

:coat :coat

 

[Andy™]

But not all panels allow you to use a zone as a tamper, and unless the veritas has changed you can't do it with the Veritas. You can program a zone as 24 hour but it will still be a positive loop and does not comply with the standards when used as a tamper circuit. It will activate the alarm when unset and it will give you a zone indication but that's only half the story. The tamper loop should cause an alarm activation when it's shorted to a zone loop and using a zone will not achieve this.

the veritas can be used with a zone as a tamper (Zone type 5 IIRC). and the tamper does put the panel into fault when the circuit goes O/C

 

[Andy™]

But then your tamper circuit would only be active when the panel is set, surely it should be active 24/7?? :coat :coat

no, fire, PA and tamper are 24 hour monitoring. only guard, entry and inhibited entry are active when alarm is set

 

[oliver1234]

Yes it will if it goes open circuit but imagine you have a six core going to a passive, you connect the alarm pair to zone 1 and the tamper to zone 2 what will happen if you short the cable between the alarm pair and the tamper pair?

 

[Andy™]

Yes it will if it goes open circuit but imagine you have a six core going to a passive, you connect the alarm pair to zone 1 and the tamper to zone 2 what will happen if you short the cable between the alarm pair and the tamper pair?

have to admit i havent tried it. but the same logic goes of what if you short the cable between zone 1 and tamper. so that isnt going anywhere.

 

[NozSpark]

Didn't know that you could set a zone as Tamper!

:coat :coat:coat:coat:coat:coat:coat:coat

:coat :coat:coat:coat:coat:coat:coat:coat

:coat :coat:coat:coat:coat:coat:coat:coat

 

[Andy™]

Didn't know that you could set a zone as Tamper! :coat :coat:coat:coat:coat:coat:coat:coat

:coat :coat:coat:coat:coat:coat:coat:coat

:coat :coat:coat:coat:coat:coat:coat:coat

they are quite flexible with what you can do with them

 

[oliver1234]

Ahhh but it is going somewhere!

Conventional alarm wiring as opposed to the newer end of line or fully supervised loop as it's more accurately called is called double pole wiring. The poles are negative and positive. The tamper loop in all modern panels (and most old ones) is negative and the alarm loop is positive.

If you place a short between the tamper loop and any alarm loop the alarm zone will activate. (you can use this to connect open circuit detectors like pressure mats).

From a security point of view this is important, imagine this scenario, you wire a door contact direct to the panel and you use a zone programmed as 24 hour as a tamper.

If the cable gets trapped nd all cores short together there would be no indication of a fault and the alarm would not activate if the door were opened.

If you use a proper tamper loop (negative loop) the alarm wouldn't set if there was a short on the cable and if the short occured when the system was set then the alrm would ativate.

That's why your proposal of using a zone is great for fault finding but it doesn't comply with the standards.

 

[oliver1234]

Didn't know that you could set a zone as Tamper! :coat :coat:coat:coat:coat:coat:coat:coat

:coat :coat:coat:coat:coat:coat:coat:coat

:coat :coat:coat:coat:coat:coat:coat:coat

I don't think you can, I used to fit loads of Veritas panels and unless they have changed recently or I am very much mistaken you cant.

 

[Andy™]

I don't think you can, I used to fit loads of Veritas panels and unless they have changed recently or I am very much mistaken you cant.

You have been able to do this with veritas for at least 4 years that ive been using them. check the manual page 22. clearly states what zone types are what

1: push to set

2: inhibited entry

3: guard

4: fire

5: tamper

6: entry'exit

7: PA

8: keysiwtch

Fire, PA and tamper are 24 hour zones.

Tamper works be having a closed circuit, open circuit is fault. same as the zones, so if you your example all are shorted, then you will get the same problem if the tamper is connected to global tamper or a zone set as a tamper. maybe if you tried reading the book you wold get some idea of how it works.

 

[oliver1234]

I apologise for my poorly worded previous reply and yes you are right a zone can be programmed as tamper and yes it will activate the alarm whether it is set or not when the circuit is opened but what it will not do (unless I am mistaken) is change polarity from a postive loop as it is normally to a negative loop which is what the global tamper is.

It will still work purely as a tamper but that does not constitute double pole wiring which is a fundamental requirement if you want to install to the standards.

As I say, I may be wrong, but I am connecting a speech dialler to an R8 some time this week so I will try it.

I have no doubt that a tamper zone will activate the alarm I just have doubts that a fault will be registered if there is a short between a guard zone and a tamper zone.

 

[Andy™]

If i get bored through the week ill get a spare panel set up and try it.

 

[oliver1234]

Well it will be an interesting experiment and I'm really not being deliberately argumentative, I would certainly like to see spare zones used to split the tampers up to make fault identification easier, it does make sense.

Even if it doesn't show a fault if there is a short to a guard zone there is no reason why you couldn't use a zone programmed as tamper to monitor periphial devices like internal sounders or speech diallers.

It only becomes a problem (as far as the standards are concerned) if you use a tamper to protect a detector and both loops are the same polarity.

The standards were written this way because, particualry in a commercial environment, it would be relatively easy for a prospective burglar to short all 4 cores of a cable together during the day time then come back at night and burgle the premises if the short didn't show up as a setting fault.

I must admit I like using end of line wiring, it takes a bit of getting used to but it is so much more secure plus you only need to run a 4 core to a PIR, and you get built in identification of tampers to the specific device.

 

[Badger]

If i get bored through the week ill get a spare panel set up and try it.

IF being the magic word :^O :^O :coat :coat:coat:coat:coat