Dave Vondrasek wrote:
On the radio side of the
> Bulkhead connectors, each has a Alpha Delta Transi-Trap Lightening Surge
> Protector (ATT3GHP) rated at 2000 watts each up to 3GHz. The ground post
> from each of these is also feed down to the Grounding Bar with #4 stranded
> copper wire.
Hi Dave,
It sounds like you are on the right track. I would install more ground
rods with more radials going out from your common connection point.
Especially at the house end. It sounds a little light there. Even just
some buried radial will help.
You should also install some protection device for the power system. A
whole house protector would not be a bad idea. With the main panel right
at your single point ground it should work rather well.
I am not sure but I think that the NEC wants to see a direct connection
to a ground rod right from the service entrance panel. If 2 rods are
required because of high ground resistance the second rod, if I remember
right, is supposed to be connected with a continuos length of wire with
the first and the panel.
You can then run as many leads as you want from those ground rods or the
power ground lead over to your common point ground connection
I don't know much about the alpha delta coax devices but I don't think
that they have a capacitor to isolate the equipment end. If not that
means that the lightning voltage on the line would first have to burn
through, for example, the receiver front end coil in order for the
voltage on the cable to rise high enough to fire the gas tube. Not what
you want.
Also a single device that is rated up to 3 ghz will probably not have
the proper gas tube in it either for the band of interest. That means
that the arc point will be way higher than optimum.
If I remember right, the only thing that is in the polyphaser rotator
protection boxes are some large mov's from each line to the ground
connection. I put those on my rotator line and got the mov's from
mouser. About 69 cents each??
Just remember to keep your lead in jumpers from your common ground point
clear of the cables on the other side of the protection devices and away
from the ground leads to the rods.
73
Gary K4FMX
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