On Jun 16, 2010, at 7:41 PM, Michael Baker wrote:
> Relocation is also not always practical nor is it inexpensive.
Agreed. But I found the losses from damage caused during three earlier storms
not inexpensive, either. And unlike relocating either the shack or the service
entrance, they were downright inconvenient because I had no control over their
scheduling.
In those three earlier storms, virtually all the damaged or destroyed equipment
in the house was in some way connected to _both_ the AC power line and the
telephone line. In particular, in one storm every PC in the house that had a
fax/modem connected to the phone line was totally zapped. Unfortunately, one
of those PCs was my rig control / logging PC, with a serial interface to my
rig, so my rig experienced some damage, as well.
These three lightning "events" were not caused by direct hits on my house;
rather, they were "nearby" hits, perhaps a quarter-mile away, and the damage
came from the surges on our (underground) power line and/or our (underwater!)
telephone line. When your AC service and your telco service come into the
building at different locations and each is "grounded" at its own separate
entry point, you're just asking for trouble if you have equipment connected to
both.
So, clearly, some of the impetus to collect the entrance point for these
utilities in one spot goes away if one takes care to _not_ connect anything of
value directly to the telephone line. I no longer use PC-based fax/modems;
they have been replaced by a single $50 el-cheapo fax machine for outgoing
faxes and a free efax service for incoming. Similarly, my DSL high-speed
internet service feeds a telco-supplied modem which then connects only to an
inexpensive WiFi node; there are no hard-wired connections from my telephone
line to anything in my shack. Unfortunately, there's not much I can do about
the connection from my DirecTV receiver to the phone line but since it's leased
equipment the company replaces it when it dies and all I'm out is the
inconvenience of a few days without television service.
Next, the remaining issue is whether cables to/from the shack (for RF, rotor &
remote switch control, etc.) go through a single-point ground that is allied
with the AC entrance ground. I think, if I were looking at $5,000 or more to
relocate the service entrance (or the shack, for that matter), I would simply
lengthen all my cables and make sure they came into the shack the "long way
around" -- that is, via the AC service entrance point. Alternatively, I would
disconnect them all _outside_ the dwelling after each operating period.
BTW, I am not located in an area of high lightning activity; the three storms
that caused damage to equipment were in the course of perhaps a decade. But
one of those three storms occurred totally outside our normal thunderstorm
season, on an Easter Sunday morning, with absolutely no warning whatsoever. It
was a single bolt event. So I don't recommend leaving cables connected until
you see a weather report that suggests a storm is coming; you might receive an
unpleasant surprise.
Bud, W2RU
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