Periodically losing some motion sensors

Support
1

Hi, I have a 2GIG system with several wired motion sensors into a takeover unit. On a daily basis, and at similar times each day, a small set of the sensors loses communication. Then, also at a similar time each day, communication is restored. I don’t see any low battery alerts on these. Any ideas on how to troubleshoot? Thanks in advance

2

Looks like this is a new account through us, and I only see two examples of what you are describing in history. The start times for the malfunctions are 3 hours apart.

I can’t view older data so if you have a pattern prior to getting started with Surety please let us know specific time stamps for malfunction events and the zones that reported malfunction.

In general though, there are two potential causes:

  1. Wireless signaling from the TAKE-345. Make sure it is not inside a metal panel can or attached to metal.
  2. Resistors outside of the limit are on the circuits. The max resistance on a circuit is 3kohms. If there are resistors on the circuits, remove them. Test resistance using ohmmeter/multimeter
3

Thanks for the reply

  1. The Take unit is inside a metal panel. However, only a few of the sensors are dropping out while the others are not. So, the Take unit has ~8 sensors but only 4 drop out. Would this still indicate a communication issue?
  2. Will check this out.
4

If the TAKE is inside a metal panel it should be reinstalled outside of the metal. An RF device should never be installed inside a metal case. The case can heavily impact the wireless transmissions.

Typically I would expect all associated sensors to have a problem, but if you have supervision turned off for some this would happen, and it’s possible for some supervision signals to reach the panel and some not.

5

We pulled the take unit out of the enclosure and checked resistance; max was 2.2k, most were under 100. Still seeing these periodic cutouts around the same time each day. Any ideas on what to check next? Many thanks

6

This suggests a wiring issue then, though it is very strange for four of the 8 to malfunction simultaneously and always be those four. I would recommend cutting, exposing fresh cable, and reconnecting all of those four zones at both the TAKE end and the sensor end next.

This seems to be a commercial environment, is that correct? How long are the cables to those four zones?

Does the wiring for those four zones run parallel with any high voltage wiring for a distance? This can have odd effects and may explain why all four occur together.

7

I appreciate your help on this. The resistance on the other sensors was less than 100 ohms. Could that be too low of a value for the system to consider it functional? These values are to be measured without power and disconnected from the TAKE, correct?

8

No, the TAKE accepts anything up to 3kohm.

These values are to be measured without power and disconnected from the TAKE, correct?

Sensors should be powered, but disconnect the zone’s sensor circuit wires being tested.