Cross-Zone and Self-Verify (Elk)

rcharris

Member
All:

I am looking for some advice and opinions on how best to avoid future false alarms from a motion sensor by using the cross-zone pool in the Elk M1G.

My Installation: Elk M1G, 28 wired zones, Ethernet, Wireless for keyfobs only. Most perimeter rooms and great room have pet-immune Dual Technology motion sensors (Rokonet Cosmos Pet DT) and Glass Break sensors (Visonic Glasstech). All exterior doors and ground-accessible windows have magnetic switches.

What happened: Yesterday, while at work, I received the automatic voice call from the system announcing burglar alarm activation. (I do not have a monitoring service at this time). As soon as I acknowledged the alarm I checked e-mail and found the e-mail alert message from the M1XEP announcing the alarm. I called neighbors who graciously offered to check the house. They reported that all was secure, no evidence of break-in. (wonderful neighbors). They reported no sirens (but time-out is only ten minutes), but that the strobe light was flashing, indicating that Elk had truly decided there had been an alarm.

To make a long story short, the log shows motion detected in a ground floor room, that set off the alarm, a "false" alarm I am certain. We do have a cat, but in the 10 months that I have had the system running she has never set off a motion sensor before. It may have been that she some-how managed to trip the sensor this time, perhaps in concert with late winter afternoon sun, or it may have been a sensor or Elk malfunction. Does anyone have opinions or comments on that?

I would like to reduce the chance of future false alarms, and am considering the cross-zone and / or self-verify functions in the M1G. I would like to know if anyone has comments, advice, or "best-practice" guidance on the pros and cons of self-verification versus cross-zone verification. I do not have more than one motion sensor in any given room, so cross-zone would require an intruder to go from room to room to set off an alarm. Self-verification would remove that limitation, but might miss an intruder who left a room and managed to avoid any other room with a motion sensor.

Thanks for any comments or advice!

Regards,
Rod Harris
 

rfdesq

Senior Member
rcharris said:
It may have been that she some-how managed to trip the sensor this time, perhaps in concert with late winter afternoon sun, or it may have been a sensor or Elk malfunction. Does anyone have opinions or comments on that?
I had the same problem with cats in one of my installs. I tweaked the motion sensor on its bracket to be as vertical as possible i.e. minimizing the downward look. The instructions said not to use a bracket at all but to mount the sensor flat on the wall. You have a good handle on the pros and cons of using self verify. I am interested in reading what others have to say.
 

cliffs

Member
Your problem is with the cat not your system. Cats love to jump up any
almost anything. You would surprised how far they can jump. They are smart enough to know that when you are home they are not supposed to be up on things, but when you are away they forget.

If they stay on the floor the motion sensor won't pick them up, but on the
back of a chair or couch it will. Very common problem.

Cliff s
 

Spanky

Senior Member
If you have a CAT problem, I would use two motion detectors using cross zoning on each zone. If the CAT fires one zone hopefully it will not set off the other zone within the cross zone time.

FYI: Cross zoning allows for numerous zones to be ANDED together so that if one of the crosszone defined zones activate another zone must be triggered within a programmable time before the alarm will trigger. The M1 can be programmed for self verify which means a zone can be tripped, restore, and tripped again within the time window and cause an alarm.
 

rcharris

Member
=Spanky,Nov 12 2006, 09:09 AM
.....
FYI: Cross zoning allows for numerous zones to be ANDED together so that if one of the crosszone defined zones activate another zone must be triggered within a programmable time before the alarm will trigger. The M1 can be programmed for self verify which means a zone can be tripped, restore, and tripped again within the time window and cause an alarm.

Spanky:

I am not sure from reading the installation manual as to the definition of the time window: Is it a) from the time one zone becomes violated to when the next becomes violated, or b) from when the first zone becomes secure (after being violated) to when the next zone becomes violated? What about for self-verification?

Example, assume the time window is 15 seconds:
Time 00:00 Zone 1 violated
Time 00:06 Zone 1 secure
Time 00:16 Zone 2 violated, No Alarm (00:00 + 00:15 window = 00:15)
-or-
Time 00:00 Zone 1 violated
Time 00:06 Zone 1 secure
Time 00:16 Zone 2 violated, Yes Alarm (00:06 + 00:15 window = 00:21)

for Self-verify is it:

Time 00:00 Zone 1 violated
Time 00:06 Zone 1 secure
Time 00:16 Zone 1 violated again, No Alarm (00:00 + 00:15 window = 00:15)
-or-
Time 00:00 Zone 1 violated
Time 00:06 Zone 1 secure
Time 00:16 Zone 1 violated again, Yes Alarm (00:06 + 00:15 window = 00:21)

Thanks in advance
 
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