Re: [TCML] Grounding Coil to Water Pipe

[Skip Malley <skip@xxxxxxxxxxxxxxx>]

I know this is old, but it is an email that accidentally never got 
sent.  I hope it will be considered useful.

After reading all of the grounding emails (back in September), I 
thought I would sum things up and add my two cents

This is a very complicated subject.  One thing to keep in mind is 
this simple, but potentially confusing fact:  There is no such thing as GROUND.

How can I say this you may ask?  GND is not GROUND until it is in the 
DIRT.  I mean that literally.  It is not GROUND until you are in the 
wet conductive dirt of the planet (this becomes more complicated if 
you are in the desert areas of the southwest where there is little 
wet dirt).  Everything else is just a connection to GROUND.  These 
connections have distance and resistance (and impedance).  These are 
also compromised by other GND connections connected to each 
other.  These connections look like a big tree with the trunk at the 
DIRT surface with multiple roots going underground.  The trunk and 
branches are the various safety grounds of your electrical system and 
copper water supply pipes in your house along with the electric 
service entry from the utility pole outside your house.  These are 
all usually brought together at a single point at your electrical 
service panel or very close.

The root system is the actual connection system to the DIRT (yes, 
brown and wet).  These consist of a grounding rod or two required by 
most electrical codes.  Normally any other metal pipes entering your 
house are required to be connected at the electrical service 
box.  This is normally your main circuit breaker panel.  Some details 
may vary if you have a separate service disconnect breaker that is 
not part of your main distribution panel.

Regarding the Cable, Satellite, Phone, and other utility entrances 
into your house, these are supposed to be connected as close to the 
central GROUND point as possible.  This is also normally required for 
a roof mounted antenna  This is often done by connecting to the wire 
from the service box to the outside grounding rod.  That puts this 
connection as close to the DIRT as possible.

HOUSE GROUNDING REQUIREMENTS BY NATIONAL ELECTRICAL CODE
One thing to remember is that the NEC requirements for grounding are 
only concerned with 60 HZ safety issues.  These are only for issues 
with shorts and leakage currents from faulty connected 
equipment.  They are there to protect a user from contacting 120VAC 
shock hazards.  While most of these codes and requirements would 
often make a decent RF ground, there is no guarantee unless you 
connect where the ground wire comes out of the ground.

THE AC GROUNDING TREE
In the case of an equipment failure that may put 60 Hz current into 
the GND system, it is returned to GROUND without creating any harmful 
voltages to anyone touching any other device.  Again, this was to 
prevent human harm.  In this case, the tree effect in insignificant 
since all impedances are low.  In the case of 60Hz, it is 99.9% DC 
resistance only.  That changes at RF frequencies.

RF GROUNDING
In the case of any radio frequency induced currents, there may be 
significant voltages at any of the tree's branches or connections 
that could easily damage electronic equipment.  Using an electrical 
system GROUND or plumbing system GROUND is only useful if it is close 
to the DIRT.

As stated and seems to be the general consensus, the best Tesla 
GROUND connection is a separate one to the DIRT as directly as 
possible.  In many homes that I have seen, the AC comes into the 
house at the garage with the GND rod just outside.  In that case, run 
a simple but separate connection to the GND rod.

GARAGE SYSTEMS ALERT!!!
A bunch of users seem to have garage available for Tesla use.  You 
may have a great GROUND available since your power distribution panel 
may be in the garage.  You also have the garage door opener to 
protect.  These are probably OK from the power line, but would need 
some protection from the door switch wire acting as a long antenna 
.  This would probably be OK if some .1 or 1.0uF capacitors are 
connected between the terminals and between each terminal and the 
case of the opener.  That would bypass any RF currents into the case.

I hope this clears things up for some and produces a better 
understanding of grounding details.  If anyone would like to add to 
this, please let me know off list and I will gladly enhance it and 
make it available with any improvements.  Can anyone provide any 
diagrams that might be a nice addition?

Happy coiling.

Skip

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