Michael A. Terrell wrote:


Yes it is not a good policy to tie the ground and neutral together. I
just felt that a good explanation of why not to do so was required
instead of just a blanket statement stating "The safety ground must
NEVER be connected to the neutral at the load !NEVER! "

But he on the safe side and ground those boatanchors together. (you can
buy a bigger boat that way).

Thanks
Ron WA0KDS


Ok, Ron here is another possible failure mode: The neutral from the
pole pig goes high resistance or completely open. if both halves of the
240 VAC service are not balanced and the imbalance will cause a current
to flow from the neutral wire, to the radio and back to the ground rod.
If that current is very high the cord will smoke or burn. I had to
replace a breaker box a few years ago after the neutral corroded to the
point it exploded. I was outside at three in the morning repairing the
damn thing to cool my bedroom down so i could go to work the next day,
but nothing had the suggested wiring, or I could have lost my home.
Also, you could have trouble collecting from your insurance company
after a fire caused by your own work.

Hi Michael,

Yep, that is yet another good example of why you shouldn't break the rules.

I could write all week, and still not cover all of the stupid dangerous things
that have happened with ground failures and grounding errors. The NEC
is the result of 100 years of experience with power distribution, and use.
Their collective authors have seen some of the most bizarre failures, and the
code has been designed to help prevent these types of failures.

It is rather unsettling to have a line cord catch fire in the bedroom
when your wife puts a piece of toast in the toaster oven in the kitchen.

And we haven't even broached the subject of what happens when your antenna
gets hit by lightning, and you have invited the ground currents into your
neutral circuits!

In case anyone thinks that losing the connection to the center tap (neutral)
at the pole pig is an unlikely problem. Bear in mind that virtually all
of these connections are to aluminum wire. The power companies make their
own rules. They don't have to follow NEC, they have their own code.
When they started using aluminum wire exclusively in the '60s,
they didn't think about the corrosion and cold flowing characteristics of
aluminum. The power companies use aluminum exclusively for all of the wiring
on their side because aluminum has the highest conductivity per pound, and per
dollar, of any known material.

After they gained experience with aluminum, and knew all about its problems,
I bet you think they went out, and upgraded all of the older connections,
right? Nope! They left them alone. Power companies are profit driven, they
didn't want to have to explain to their share holders why they would have to
shoulder a billion dollar loss to fix a problem of the power company's making.
So, they only fix the problem when *you* discover it.

-Chuck