Re: Adding a third keypad to a Caddx NX-8, wiring help requested!

[Robert L Bass <sales@xxxxxxxxxxxxxxxxxxxxx>]

> "Shielded wire traps and drains (among other things)
> RF interference and AC induction away from sensitive data
> circuits."

Use shielded cable for keypads *only* if the manufacturer
specifies it.  Some systems are actually made worse by using
shielded cable.  In most cases it is not recommended by the
manufacturers.

> "Remember to ground only one side of the shield to an earth
> ground connection. Grounding both sides to the ground creates a giant
> dipole antenna and introduces damaging interference instead of draining
> it away. Twisted wire reduces the amount of interference, but just not
> as effectively as shielded."

> I guess they are also lying when they say this.
> "Twisted wire reduces the amound of interference...."

What's an "amound" of interference?

You're confusing stranded wire with twisted pair cable.  I said
nothing about TP cable.  However, now that you mention it, there
are also some systems commonly installed by alarm companies which
are better off using parallel (non-twisted) cable.

By the way, the guy who wrote the page you cut and pasted above
isn't an engineer.  He's just an installer who wrote an article
for an online magazine.

--

Regards,
Robert L Bass
http://www.bassburglaralarms.com