Electronic Alarms and Home Security Devices - False Alarm w/Ademco PIR on Vista 20p

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MAS
02-07-07, 08:55 PM
Got my neighbor's attention with a false alarm today. An interior motion was set off with no sign of entry and doors still locked and untripped...no pets either! I've had the system live for over a year now, and this is the first sign of a possible problem.

The motion is hard-wired to a vista 20p control.

I like that my neighbor investigated & I do not want them to lose interest.

I checked for dust on the lens cover, but none was to be found.

Is this unusual for an ademco, and how should I preceed & what should I check?

Thanks for your input,

MAS


umpire1101
02-07-07, 09:38 PM
it is not unusual for a motion to false. You have to remember that motion detectors today are looking for two things: heat and movement. It probably has nothing to do with the main alarm panel..

things to look for are:

loose papers or curtians that would blow around when the heater fan starts to blow.
Milar balloons in the room that would blow around when.....etc...

basically, when things change that would have heat and motion the detector will think that it is "someone" moving around in the room.

check these things first.

and, sometimes motions just go bad, just like good kids when mommy ain't around.

MrRonFL
02-08-07, 05:38 AM
All that Umpire said, and also a common heat/cooling false alarm is when the air has been still and stable for a while, and suddenly the heat or air kicks on, that sudden blast of much hotter or cooler air looks like motion (remember these things only see changes in ambient temp).

As long as it doesn't become recurring, it's likely just dumb luck.


MAS
05-15-07, 09:32 PM
OK...I thought all was fixed. I replaced the motion about a month ago...then I had another false last night. It got me right up!!


I do not have any pets. The heat was not on. Nothing fell from the walls. And no intruder!

Where do I go from here?

Could it have anything to do with the EOL resistor? I have the motion on a dedicated zone with the ELO resistor on the "high."

Thank you for all the help, you guys have been great in the past!

Mas

MrRonFL
05-16-07, 05:56 AM
Assuming that your wiring has no damage, false trips from motion detectors are almost always environmental. Even something as flaky as a moth landing on the lens can do it (a 2 gram moth looks very large at contact range). I've seen repeat false alarms come from a silverfish that found it's way into the detector housing.

Check all of the connections and give the terminal screws at each end a turn from the screwdriver. The resistor has nothing to do with it. A resistor is a resistor, so long as it is the correct value, and has a solid connection to the wire.

Without actually seeing the space involved, this is not something that can be reasonably diagnosed with second hand information.

blakemster
06-28-09, 05:12 PM
MAS ~ I am having the exact same issues. I have had this property and alarm since 2003 and NOT 1 false alarm ... I had some work done and now I am getting false alarms for no apparent reason. I recently changed ALL the motion detectors to BOSCH and I am still having these issues. No heater or air ''on" ... nothing! No bug or rat droppings! I am at a loss and don not know what to do next???

DID YOU EVER GET YOURS WORKED OUT?

MANY THANKS, BLAKE

MrRonFL
06-28-09, 08:37 PM
There is one other thing to check: The condition of your system battery. If it is getting long in the tooth, should there be a momentary brownout, the backup battery voltage can drop enough to let the relays in the motions drop open.

If you are getting multiple motions tripping at once, this is a likely cause. Otherwise, as previously posted check your connections at both the device and the motherboard. The wire does compress and loosen in the connectors given time.

I'm still betting on environmental...