Re: Datalogger to Test False Alarms on Sensor

[Nomen Nescio <nobody@xxxxxxxxx>]

will said:

>Of course, but doesn't that mean running separate wires to the two sensors?
>The run is about 200 feet on a warehouse ceiling.   I was looking for a fast
>and dirty way to monitor the potentially defective sensor without resorting
>to a long wiring job.

No.  You'll use the "polling loop" on the panel to expand the number of
zones.  You have four conductors going to the existing sensorr, two for
power, and two for the zone.  (By the way, at 200 feet you might want to
check the power supply voltage at the sensor to see if you have adequate
voltage, depending on what else you may be powering from that wire run.)
Disconnect the zone wires at the panel and at the sensor.  Install a 4208U
near the sensor.  Connect the zone wires to the polling loop output on the
panel.  Add the new zones in programming.

For your application, you might want to read up on cross-zoning.  I think
the 128BP supports that.  This means you don't get an alarm unless both
sensors trip within a certain time period.  I think Ademco also reports a
trouble when only one zone trips, but read the manual to be sure.

Final point:  if you've been replacing the sensor with the same brand and
model, don't.  Use a different brand of sensor that covers the same area.

- badenov