Elk - one zone not working properly

[jleach8]

I finished up a new Elk install a couple of weeks ago. I have 2 windows in my garage that are wired to one zone. The other night at 3:30 AM the alarm went off....I went down to check and both windows were secure with no signs of tampering. I checked ElkRP and the voltage for that zone said 0.1 rather than 0. It went back to 0 after a few seconds of watching it.

I set up a rule that will email me whenever that zone goes not secure, and it's emailed me a couple of times even though the windows were not opened.

Is the likely cause of this a bad wire? bad sensor/magnet?

 

[42etus]

Bad wire. Perhaps a staple in it. When secure, there should be about 7 volts across the zone, when not secure there should be about 13 volts. Since you have ~0 volts, this indicates that the wires are shorted to each other, bypassing the EOL resistor.
YMMV,
Paul

 

[AceCannon]

Take your continuity tester / multitester to the window and measure resistance / continuity across each window sensor.

 

[WayneW]

When secure, there should be about 7 volts across the zone, when not secure there should be about 13 volts. Since you have ~0 volts, this indicates that the wires are shorted to each other, bypassing the EOL resistor.

That is assuming he is using an EOL resistor. Without a resistor, 0 volts is normal for a normally closed secure loop.

 

[jleach8]

I am not using an EOL resistor. All zones are NC and report 0 volts, with the exception of this one, which seems to read 0.1, but only once in a while (it's happened twice in about 7 days). I used the continuity tester and the wire seems OK...

 

[42etus]

In that case, I'd suspect a sensor. I assume (yeah I know) that the two sensors are in series with each other. Is your installation such that you can read across each sensor with a voltmeter and see which one is causing the 0.1 volt drop?
Try putting the wires into a different zone in the Elk. Perhaps the problem is in the M1 and not in your installation at all.
Can you create the problem by tapping on the sensors or magnets?

 

[AnotherOne]

Move the wires to another zone on the elk to make sure the problem follows the wires.

 

[Sandpiper]

.......Is the likely cause of this a bad wire? bad sensor/magnet?

Another, more likely, possibility is the magnet and sensor are not properly aligned or are too far apart. You can rule out the wire and connections by testing the resistance. Typically there will be 3 to 6 ohms in the loop. If there is more than that, check the connections. But also check the magnet alignment and distance. You could try to upgrade the two magnets to the rare earth type.

 

[jleach8]

Thanks for all the suggestions. I'll try moving to a different Elk zone and swapping the magnets. If a zone is disabled, would I still get the email rule I setup if the zone goes not secure, or would I need to enable it? I just can't afford another false alarm at 3:30 AM...wife was not happy when BOTH kids woke up

 

[AnotherOne]

Set the Zone to "16 - non alarm"