4th attempt to post....
Ed asked:
<< I would think you'd want the equipment chas-sis to remain grounded.
That way the equipment and AC ground is the same potential at all times, and
a local rise in potential won't result in surge into the AC power cord
feeding the unground "floating" equipment.
If you isolate the equipment from ground, you should also unplug every AC
power cord to prevent the above type of surge from happening. Of course a
good surge arrester would help, but I'd think that grounded equipment would
reduce the need to rely on the suppressor. Wouldn't it? 73, de ed -K0iL >>
Hello Ed,
More good questions!
If the equipment were adjacent to conductors that were dissipating direct
strike current, such as on the tower, where the potential for side-flash
between metallic objects is large, then I would say yes, I would want the
objects to be grounded to rise and fall with the enormous electrical
potential.
However, in the shack, I should (hopefully) be dealing with reduced, induced
surges on lines from magnetic pulse in the near field of a strike. From what
I have been able to gather about lightning energy, it always finds the least
inductive path to ground, and I don't want my equipment to become any part
of that path.
If lightning strikes my shack, instead of the lightning rod at 126' on top
of the mast of the tower, then I may have to rely on insurance! I'm
counting on the rod to take the strike since the tower is only spaced 40'
from my home.
Ed, I think you just got me convinced to install a second air terminal
above the shack roofline and bond it to the panel ground conductor.
Another thing that works in my favor is that the only thing I have plugged
into the wall is a battery charger. All the other hamshack gear runs
directly off of a large, group 8D battery. I have a small inverter for the
rotator. Essentially, I am always on emergency power, hopefully further
protecting the gear and enhancing readiness.
There are varied opinions on how best to protect your gear and I am
certainly no expert in the field so I may be missing something. So I read as
much as I could here on TowerTalk and in other sources and applied a
solution that made the most sense to me.
From time-to-time, industry professionals in many fields will take the
time to post absolute gems of knowledge here, making TowerTalk so valuable.
MERRY CHRISTMAS TO ALL!
--...MARK_N1LO...--
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