Re: Gate Sensor?

[Jim <alarminex@xxxxxxx>]

On Nov 14, 5:09=EF=BF=BDpm, "Steve" <nos...@xxxxxxxxxxx> wrote:
> RV storage area with two 15ft gates mounted to metal gate posts not attac=
hed
> to the main building. =EF=BF=BDLooking to put a contact on it. =EF=BF=BDA=
nything readily off
> the shelf?
>
> GRI makes 3/4 and 1 inch contacts for metal doors. =EF=BF=BDAnybody make =
1/2 inch
> ones?
>
> Thanks

Just a suggestion:

If you are going to use a contact, make it a SPDT and make the circuit
a UL connected contact. That is: Use a four wire and set up the switch
to open the loop and additionally short out the EOL. The EOL should be
located inside the building. All connections should be soldered and
silicone sealed. Also, if you're going to use the armored cable
suggestion as the loop between the gate and the post, use stranded
wire or see if you can utilize the wire that is normally found in a
door cord. It is stranded but has many more strands than normal four
conductor wire. ( there's a name for it, but I forget. Maby Litz
wire?) If you can't find the wire as a separate item, you can
canablize a regular door cord. I think ADI still carries the old
Ademco "long" door cords.

I don't know if the GE contact that was recommeded here is the one
that I've used in the past but Sentrol used to have an outdoor wide
gap "balanced"  magnetic contact that would be pretty damn hard to
beat. As soon as you bring another magnet near it, it trips. You'd
have to check with GE to see if they still carry it. The big "however"
is .... the other thing mentioned here .... Mag contacts on gates need
adjustment through the years  ............... and NOT mentioned
here ...... the contacts are subject to being welded together by
lighting hits.

You might try cameras with motion detection activated too. On one job
I ultimately had to go that route due to lighting destroying the
contacts every summer.

Depends on the value of what's being protected.