Aztec alarm

robs1

I have a fault occuring every once and a while.were my alarm is not set but goes off. It sounds strange but seems to go off on Sunny days between 10 and 11. My panel says 17 call engineer

fred funk }{

Are you sure it says 17?

KoolKid

I'd say it's 77.
What displays after you disarm the system after an activation?

altor

robs1 wrote: »

I have a fault occuring every once and a while.were my alarm is not set but goes off. It sounds strange but seems to go off on Sunny days between 10 and 11. My panel says 17 call engineer

17 indicates a faulty sensor on a loop.
If it is going off like you say it may be an environment issue.
Any PIRs facing a window or getting a glare at this time?

robs1

When it goes off it comes up on the panel zone 3 and then flashes up sensor contact panic. the only pir i have is in the hall and is well shaded. somone said to me it could be the end of line resistor going and with the sun shining on it causing this problem. i have never heard of thus before. yes its 17 showing

KoolKid

Sounds like a very bad connection on zone 3 possibly the EOL resistor is not tight.
Sensor refers to shock sensors and not the PiR.

altor

robs1 wrote: »

When it goes off it comes up on the panel zone 3 and then flashes up sensor contact panic. the only pir i have is in the hall and is well shaded. somone said to me it could be the end of line resistor going and with the sun shining on it causing this problem. i have never heard of thus before. yes its 17 showing

If it is showing 17 and not saying anything to do with the end of line resistor then it may be a faulty device or two on this zone.
The only way to check this is with a multimeter.

robs1

How should i check with a multimeter. do i disconnect each device

KoolKid

Disconnect the zone from the panel & remove any end of line resistors,
Set you meter to continuity and connect the pair to the 2 meter leads.
on a lenght of cable long enough to reach all your windows on zone 3.
Make a note of the reading in ohms. One by one tap evey sensor & open and close every contact. After a tap or an open close the resistence should return to the around the same value. If it does not disconnect that device , close of the pair wired into it & move on. Replace any that you had to close off.

altor

robs1 wrote: »

How should i check with a multimeter. do i disconnect each device

You could if you wanted to do it that way. Just remove the resistor to close off the end of the zone and do the same in the control panel. Another option if you can get someone to give you a hand is to just get them to stay at the control panel with the meter with resistor taken out of the end of line. Set the meter to 200 ohms. The reading should be 0. Now go around taping each sensor, any sensor that does not return the meter to this value after you tapping or opening the contact, take out of the loop and move on. Replace any you find faulty. If the value is already higher than 0 then see which sensor you tap or open the contact on that returns this to 0. Take it out of the loop and check all the sensors again.

KoolKid

If you are metering out the entire zone from the panel the reading will be higher than zero. An average 3-4 windows could read around 5 ohms or more depending on the length of the cable. If its excessively high to start with close off each sensor one by one to see which brings it back down.
Then test the other sensors by tapping each one a few times & check if the value returns to the same level. Ignore percentages of one ohm in the difference. eg 5.1ohms to 5.3ohms or 5.4ohms wouldn't warrant changing the device.

altor

Are you checking this on continuity or ohms

robs1

That's great lads ill give that a crack tomorrow

altor

robs1 wrote: »

That's great lads ill give that a crack tomorrow

Your welcome, any problem let us know.

KoolKid

altor wrote: »

Are you checking this on continuity or ohms

Ohms of course

altor wrote: »

Set the meter to 200 ohms..

altor

Must of being lucky over years: Always get 0 unless there is a faulty device and that would be with 8 or less devices, sometimes even more.

fred funk }{

altor wrote: »

Must of being lucky over years: Always get 0 unless there is a faulty device and that would be with 8 or less devices, sometimes even more.

You should almost never have zero. There's always some resistence.

altor

You say almost?
If there is a fault then yes there would be a higher resistance.

fred funk }{

Yes, almost. Depending on the gauge of the cable, the bigger the gauge the less resistance. With a pair of seven strand alarm cable there's relatively high resistance over a small distance.

altor

fred funk }{ wrote: »

Yes, almost. Depending on the gauge of the cable, the bigger the gauge the less resistance. With a pair of seven strand alarm cable there's relatively high resistance over a small distance.

Never came across this but will keep it in mind.

KoolKid

Even a perfect run with one perfect sensor an average cable run in a normal house will show a couple of ohms. Connecting directly to a perfect sensor you may get closer to zero.

fred funk }{

altor wrote: »

Never came across this but will keep it in mind.

How do you test for a faulty sensor on a zone? Just curious, we might be talking about two different things.

altor

fred funk }{ wrote: »

How do you test for a faulty sensor on a zone? Just curious, we might be talking about two different things.

I set my meter on 200 ohms to test the devices.

KoolKid

By connecting the meter to the entire zone at the panel?

altor

KoolKid wrote: »

By connecting the meter to the entire zone at the panel?

Disconnected from the panel, yes.

KoolKid

Just to be sure I'm getting this right. You take out the EOL(S) and then connect the cables at the panel to your meter & get a reading for the whole zone?
If your doing that the reading would never be zero.

altor

KoolKid wrote: »

Just to be sure I'm getting this right. You take out the EOL(S) and then connect the cables at the panel to your meter & get a reading for the whole zone?
If your doing that the reading would never be zero.

Really???
Are you trying to say I lie?
Here we go again....

KoolKid

Any engineer will tell you any length of cable with any number of devices will have some resistance on the cable. An average upstairs of a house with 5 or 6 windows on a loop would be 4 or 5 ohms for example.
Zero ohms would be a direct short on a meter or so of cable.

altor

I am an engineer. I am telling you what I am getting on 200 ohms.

KoolKid

http://www.cirris.com/testing/resistance/wire.html

KoolKid

By the way alarm cable would probably be around gauge 22.

altor

That is the value I am getting.

Jnealon

If you are getting zero ohms then something is wrong.
Every conductor has resistance, if it has no resistance then there no volt drop and no I Squared R losses. If I had a conductor with no losses then I would be a millionaire.
200 ohm range is too big imo, auto range is more accurate

altor

Jnealon wrote: »

If you are getting zero ohms then something is wrong.
Every conductor has resistance, if it has no resistance then there no volt drop and no I Squared R losses. If I had a conductor with no losses then I would be a millionaire.
200 ohm range is too big imo, auto range is more accurate

Will try that next time.
It always identifies a faulty device though.

Jnealon

There's nothing wrong with the meter, it just doesn't show the decimal places so all you see is zero.
My guess is you have one of these


I use this one

KoolKid

Even without decimal points most runs with a few devices is going to be over 1 ohm.
+1 on auto ranging as well.

altor

Jnealon wrote: »

There's nothing wrong with the meter, it just doesn't show the decimal places so all you see is zero.
My guess is you have one of these


I use this one

That is the issue so
Thanks again.

fred funk }{

altor wrote: »

Disconnected from the panel, yes.

Regardless off what type of meter you have or whether it shows decimals or not, If you are metering it out from the panel you must get a reading of at least several ohms. Very strange.

Thunderbird2

Calm ...... How would you test multiple sensors that are none EOL directly from the panel ???? I've seen it been done but was never phisicaly shown I would open each sensor and test that way

KoolKid

I'm calm.......and confused
You take the pair out of the panel and connect it to your meter and measure the resistance . Its generally a few ohms depending on the length of the run & the number of devices etc. You tap each sensor & open/ close each contact . The resistance should return to its initial value each time. So if, for example , the meter shows 6.5 ohms to start off with, and you tap a sensor a few times & it jumps up to 20 ohms and stays there. That sensor would be faulty . You would then disconnect that , close it off & check the rest. Remember there may be more than one faulty device on a zone that giving false alarms.
Also checking the entire zone this way will also show up poor connections, so its more reliable than just checking individual devices.

Thunderbird2

Would poor connections result in resistance?

KoolKid

A bad or loose connection would cause higher resistance , yes.

altor

fred funk }{ wrote: »

Regardless off what type of meter you have or whether it shows decimals or not, If you are metering it out from the panel you must get a reading of at least several ohms. Very strange.

If I was Fred I would tell you but I am not.

KoolKid

Better tell these their calc is wrong. :rolleyes:

altor

I am sure you have sent them an e-mail so.

KoolKid

And try convince them of the impossible ? There are people here much better at that than me.:rolleyes:

altor

Lucky it doesn't stop my good work.

KoolKid

No one is suggesting otherwise. It's just your in the business so long I imagined you would know what resistance to expect on different zone runs. It's the basic principle of how alarms work after all.

altor

I would hope not

KoolKid

Still , when you discover the secret of getting zero resistance make sure you share your millions with us all.

altor

That is no problem
I am sure jnealon will be looking for his share, it is the lease I can do