Re: Conduits in a trench

[RickH <passport@xxxxxxxxxxxxxxxxxxxxx>]

On Nov 26, 10:34 am, "Robert L Bass" <RobertLB...@xxxxxxxxxxx> wrote:
> "RickH" wrote:
>
> > If the RG6 does form a big ground loop, then make sure the shield
> > is only grounded at one end not both ends, (IOW "lift" or break the
> > ground at one end).  You'll still have a ground, but there will be
> > no potential for AC to flow in the shield due to differing ground
> > impedances at each end.  Same if you go with shielded cat5.
>
> This is true.  However, it would be wise to either provide a bonded
> ground between all three buildings (something which is probably not
> practical) or use fiber to completely isolate all current carrying
> conductors.  Even data lines inside a shield can carry destructive
> currents during a lightning hit.
>
> --
>
> Regards,
> Robert L Bass
>
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> Bass Home Electronics
> 941-925-8650
> 4883 Fallcrest Circle
> Sarasota =B7 Florida =B7 34233http://www.bassburglaralarms.com
> =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
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Yes, a shield ground lift only works if the equipment being deprived
of the shield ground also has a ground reference of its own via the
power ground.  The incoming a/v signal is then referenced to that
local ground instead of the interconnect ground which is undependable
because it is floating at some level above 0 volts, forming the hum
loop.  He did say he was running a ground wire to the other building.