Re: Wiring

[Robert L Bass <sales@xxxxxxxxxxxxxxxxxxxxx>]

On 11 Feb 2006 14:50:04 -0800, "Skinner Johnson"
<vinceinzinna@xxxxxxxxxx> wrote:

> Don't mean to be a nitpicker, but if you connect only one pair of wires
> together at a time you will never get a closed circuit because the
> other disconnected pair will keep the circuit open (assuming it's a
> normally closed circuit).

If there are two pairs of wires at the window there's a good
chance one is from the panel and the other goes to the next
sensor.  By shorting one, then the other you can find out which
pair is from the panel.

This assumes the zone is a closed loop (opens on alarm) which is
the most common type of burg circuit.

> Strip 1/2" or so of insulation from the ends of all the wires, Then,
> connect one wire from one pair of wires and one wire from the other
> pair of wires together.  If the wiring is OK when you touch the
> remaining two loose wires together you should get a ready light on the
> keypad (if everything else is closed).

If everything else is closed and if it's a closed loop, that is
correct.  If something else is open connecting the two pairs of
cables will not change the panel status.  Moreover, you still
won't know which end goes to the panel.  You could determine that
with a voltmeter, again assuming that nothing between the test
point and the panel is open.

> By the way, it is not the magnet in the window sill, but the switch.
> If you don't see some sort of button coming out of this switch (the
> closed window holds it down, completing the circuit), then it is a
> magnetic switch, and the magnet is drilled into the window itself,
> directly over the switch location.  I've seen some cases where the
> magnet falls out of the window, making the window seem OPEN, even when
> it's closed.  If that's the case, simply replace the magnet.

Yep.  I've seen that on occasion, too, mostly on older systems
with rather large magnets.  Have you seen the ones (ancient)
where a mechanical switch and magnet are enclosed in the frame
and a metal armature plate is installed in the door / window?  I
came across one of those many years ago where the client had
replaced a door and then discovered his alarm wouldn't set up.
I've run across them occasionally over the years when doing
takeovers.

--

Regards,
Robert L Bass

Bass Burglar Alarms
The Online DIY Store
http://www.BassBurglarAlarms.com