Re: why ground an alarm panel.

["Bill" <bill190nospam@xxxxxxxxx>]

Many years ago, telephones were wired with 3 wires. The 3rd was a ground.

Well they stopped running that ground wire inside the house.

I think they figured out that if these is no ground inside the house
associated with the phone system, then the lightning would stay outside?

Hard wired alarm systems have a different problem in that all the wires
running all over the place can act as an antenna, and a nearby lightning
strike can "induce" voltage in the wiring.

The question I have would be; is there "built into the alarm circuit board"
surge protection for the wiring on each zone, surge protection for the phone
line, and surge protection for the AC power lines?

And if there is surge protection in the form of zeiner diodes or MOV's, do
these short to the ground connection on the panel in the case of a surge?
(In which case I would think it would be better to provide a ground wire.
However if the ground connection is just going to the common or negative
wiring on the panel, then I would think it would be best not to connect a
ground as this would just be "lightning bait" to attract lightning to travel
*through* all the circuits on the board [rather than bypassing them] and fry
everything!)