Mysterious Alarm Trigger

[shannong]

Greetings.

 

I have the Elk M1 to include the Honeywell wireless transceiver with several wireless sensors including motion sensors.

 

I recently had an burglar alarm event occur right after arming the alarm (log below). Actually, it's happened twice in the past 6 months. Both times it was right after arming and was caused by the same wireless motion sensor.

 

On the surface it seems obvious. The zone was violated during the exit timer which is common for the door where you're exiting through if you fail to close it all the way. However, that motion sensor is at the opposite side of the house from where we exit and the door to that room was closed (most of my interior doors have sensors also). I don't see anyway possible way that motion sensor could've been legitimately triggered during the exit timer. My video system confirms there was nobody in the house.

 

The zone is set as "Burglar Interior" and not bypassable so the alarm could not have armed with it violated in the case where the signal that restored the zone after a previous violation prior to arming had been not received.

 

Any ideas?

 

Sat 1/23/2016 18:41 1 1174 = AREA DISARMED

Sat 1/23/2016 18:41 1 1300 = EXCEPTION OPENING

Sat 1/23/2016 18:27 1 1146 = RESTORE BURGLAR ZONE

Sat 1/23/2016 18:27 1 1003 = BURGLAR ALARM  ANY AREA Master-PIR (Zn 70)

Sat 1/23/2016 18:27 1 1338 = AREA 1 EXIT ERROR

Sat 1/23/2016 18:24 1 1173 = AREA ARMED

 

[Guest Digger]

If the motion can be triggered as you enter or exit then you should designate it an exit entry follower zone.  This way during the exit or entry time period it will not immediately trip.  Once the entry or exit time expires then it would trip immediately.

[shannong]

If the motion can be triggered as you enter or exit then you should designate it an exit entry follower zone.  This way during the exit or entry time period it will not immediately trip.  Once the entry or exit time expires then it would trip immediately.

 

It cannot be triggered when I enter or exit. As mentioned, it's on the opposite side of the house from where the entry/exit is with alarm panel and is behind a closed interior door.

[Guest Digger]

Something is causing the zone to violate.  It can be many things.  If the PIR is normally stable (i.e. it is not tripping and restting randomly with no known cause) they you may want to look at what can be occuring during the entry/exit time. 

 

If the detector not normally stable the obvious things are check the wiring and for anything false triggering it such as a heater, ceiling fan, the sun etc.

 

If its normally stable check for a voltage drop during the entry/exit time.  Also check to see if any automation might be tripping it. 

[Teken]

Things to consider are, is the device indicating proper RF strength? What is the voltage in the battery for this device? Does the unit have the ability to set RF tamper mode and is it on / off?

 

As Digger indicated has the sensor been installed in the correct position avoiding any HVAC ducts? Is the sensors FOV near any windows, drapes etc?

 

Have you performed a walk test to determine if the sensor is configured correctly? Does the sensor pass the POST test assuming it even has one?

 

What is the temperature in this room?

 

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In the end, we will remember not the words of our enemies, but the silence of our friends.

[shannong]

This doesn't seem to be a case of false positive trigger of the sensor. This has only happened twice with six months apart and both times were during exit. In the two years it's been installed there has never been a false positive while in the armed state so the environmental factors aren't viable candidates. The sensor points away from the two walls with windows and down away from the ceiling fan.

 

So frustrating! I guess I'll try replacing it.

 

Thanks for your replies.