Re: shielding low voltage wire, running low voltage wires aside 12-2 romex

[John M Lauck <recaffeinated@xxxxxxxxx>]

On Jan 29, 10:32 am, Frank Olson
<use_the_email_li...@xxxxxxxxxxxxxxxxxxxxxx> wrote:
> Robert L Bass wrote:
> > "John M Lauck" wrote:
>
> >> Couple questions:
>
> >> First, is it possible to run Swann security camera (black, shielded,
> >> power/audio/video in one) wire along side 12-2 romex.  I'm wiring
> >> security cameras and external motion lights and it would be much
> >> easier to run this pair of wires side by side.  Is there any problem
> >> doing so?
>
> > Don't do it.  Code requires separation for safety.  For optimal
> > performance stay 12" minimum from 110VACD and 24" from 220VAC.  Cross at
> > right angles where necessary.  That said, it's ok to run close and
> > parallel for a few feet, say up a wall to a light switch.  But farther
> > than that keep your distance.
>
> BAss, you're a moron.  So you have to maintain separation for safety
> (according to Code)...  yet it's "OK to run close and parallel for a few
> feet" (which is *against* Code)...  Your mental faculties must be on
> hiatus.  This has got to be one of the dumbest things I've seen you
> post.  "Don't do it, but it's OK if you do"...  Right, Bass.
>
> NEC requires a minimum 2" separation between high voltage (110VAC) and
> low voltage (communication grade) cabling.  If you're running
> communication grade wire down a wall which also happens to have a light
> switch, it's going to be darn difficult to maintain that separation
> unless you cut out the dry wall and physically staple the wire.  Most
> alarm installers (primates to BAss) recognize this and will use separate
> wall entry points from any AC wiring that's terminated or run in the
> same wall cavity.  Electrical inspectors will look for this.  They don't
> bring the X-Ray equipment out to ensure any wiring you've run inside the
> wall complies with NEC.
>
>
>
> >> Second, I've read plenty of info that specifies if you have to cross
> >> Cat-5 wires with electric wire you cross the two wire
> >> perpendicularly.  However, in an older home where there's only a small
> >> chase to get wires to their destination there's bound to be a place
> >> where the wires are side by side.  Can you wrap the low voltage wires
> >> with foil or something to shield them?  Is this necessary for short
> >> points of contact?  Is this the same for speaker/security or coax wire?
>
> > For short distances necessary to get to a service point from the main
> > run, it's ok to stay under 12" away.  Don't run the two types abutting
> > each other though.
>
> He shouldn't have a problem using shielded wire.  The "rule" (code to
> you) is to maintain a 2" separation.

Thanks for the tips.  I've been trying to maintain separation in all
cases but as several mentioned, it's nearly impossible in an older
(late 1800's) home to do this in all cases.  12" of separation sounds
ridiculous especially when studs are often 16" or less on center.  You
can only drill so many holes before you are doing more structural
damage than necessary.  I thought about testing it by wrapping some
low voltage wire around some hot romex and testing throughput on the
low voltage.  Has this been done and published before?