The satellite guys say that because they have connected their ground wire
into the AC disconnect that they are grounded according to NEC. I say they
have to drive a 8' ground rod and bond this to the service. I don't have a
code book and every article I have found is not really clear how this is
Anyone want to comment?
From what I read
I believe you already have a grounding electrode for you home right? If
they carried a #14 or larger ground wire out to the dish and connected that
ground wire in your service I think you covered.
An additional ground rod is a messy business.
Isn't the key connecting it to the service? They have an insulated 8
stranded draped over the side of the house swinging and then striped and
rapped around the lock hole in the AC disconnect.
They should either drive a ground rod below the dish or run the conductor to
the service panel. Right?
There isn't a lot of information given here, but I suspect the "satellite
guys" may not be licensed or even qualified to be engaged in electrical
work. At best I envision them having low voltage qualifications which isn't
a bad thing, but it might be informative to ask what license they possess.
It would be interesting to know if the disconnect they connected the ground
wire to serves the dish, or how they terminated the ground wire its self.
With the limited information supplied it's difficult to armchair the work of
the dish installers, but I doubt a ground rod would be required for this
installation. Installing a ground rod isn't a problem, and the addition to
the grounding electrode system would be a good thing, just not necessarily
required. If a ground rod is installed for the dish system it will need to
be properly connected or bonded to the existing grounding electrode
system/electrical system ground with a minimum #6 Cu conductor in an
If you call the electrical inspector having jurisdiction for your area they
are usually very helpful, and willing to discuss situations such as this
with you. You've cited NEC Article 820, but that is normally applied to CATV
systems. I would expect that the inspector would look to article 810 if your
installation is serving a single occupancy structure. If the work by the
dish vendor isn't suitable the inspector would also be able to address that.
It might be helpful to review article 810 before calling the inspector.
If this dish is on the roof it is likely one of the higher metallic elements
of the structure, and might present concern as a target for a lighting
strike. You might consider having the installation evaluated by someone
versed in electrical grounding/bonding, and lightning mitigation if your
area has a history of electrical storm activity.
Remove the two fish in address to respond
820.40 Cable Grounding.
Where required by 820.33, the shield of the coaxial cable shall be grounded
as specified in 820.40(A) through (D).
(A) Grounding Conductor.
(1) Insulation. The grounding conductor shall be insulated and shall be
listed as suitable for the purpose.
(2) Material. The grounding conductor shall be copper or other
corrosion-resistant conductive material, stranded or solid.
(3) Size. The grounding conductor shall not be smaller than 14 AWG. It shall
have a current-carrying capacity approximately equal to that of the outer
conductor of the coaxial cable. The grounding conductor shall not be
required to exceed 6 AWG.
(4) Length. The grounding conductor shall be as short as practicable. In
one- and two-family dwellings, the grounding conductor shall be as short as
practicable, not to exceed 6.0 m (20 ft) in length.
Exception: In one- and two-family dwellings where it is not practicable to
achieve an overall maximum grounding conductor length of 6.0 m (20 ft), a
separate ground as specified in 250.52(A)(5), (6), or (7) shall be used, the
grounding conductor shall be grounded to the separate ground in accordance
with 250.70, and the separate ground bonded to the power grounding electrode
system in accordance with 820.40(D).
(5) Run in Straight Line. The grounding conductor shall be run to the
grounding electrode in as straight a line as practicable.
(6) Physical Protection. Where subject to physical damage, the grounding
conductor shall be adequately protected. Where the grounding conductor is
run in a metal raceway, both ends of the raceway shall be bonded to the
grounding conductor or the same terminal or electrode to which the grounding
conductor is connected.
(B) Electrode. The grounding conductor shall be connected in accordance with
820.40(B)(1) and (B)(2).
(1) In Buildings or Structures with Grounding Means. To the nearest
accessible location on the following:
(1) The building or structure grounding electrode system as covered in
(2) The grounded interior metal water piping system, within 1.52 m (5 ft)
from its point of entrance to the building, as covered in 250.52;
(3) The power service accessible means external to enclosures as covered in
(4) The metallic power service raceway;
(5) The service equipment enclosure;
(6) The grounding electrode conductor or the grounding electrode conductor
metal enclosure; or
(7) The grounding conductor or the grounding electrode of a building or
structure disconnecting means that is grounded to an electrode as covered in
(2) In Buildings or Structures Without Grounding Means. If the building or
structure served has no grounding means, as described in 820.40(B)(1):
(1) To any one of the individual electrodes described in 250.52(A)(1), (2),
(3), (4); or,
(2) If the building or structure served has no grounding means, as described
in 820.40(B)(1) or (B)(2)(1), to an effectively grounded metal structure or
to any one of the individual electrodes described in 250.52(A)(5), (6), and
(C) Electrode Connection. Connections to grounding electrodes shall comply
(D) Bonding of Electrodes. A bonding jumper not smaller than 6 AWG copper or
equivalent shall be connected between the antenna systems grounding
electrode and the power grounding electrode system at the building or
structure served where separate electrodes are used.
Exception: At mobile homes as covered in 820.42.
FPN No. 1: See 250.60 for use of air terminals (lightning rods).
FPN No. 2: Bonding together of all separate electrodes limits potential
differences between them and between their associated wiring systems.
I'm confused, are they runnig 120V out to the dish or just the ground wire?.
Is the discconect for the dish or just somthing convient. Is the dish
metal.? Maybe this wire is a lighting ground (a different issue).
What should the installer do to ground the dish properly? My sister had 2
tvs struck by lightning before she found out her dish was not grounded (at
all) properly. She said they came out and drove a ground rod at the dish
and bonded it there. No connection was made to the house. She hasn't been
hit again but the ground rod at the dish is ok?
Ok. I saw all that but I am still unsure what the guy should do to attach
the dish ground to my house.
Does this mean that he should run a wire through the attic and open my
service panel and attach there?
Can he go in the basement and bond to any water pipe?
Is the connection he made to my AC disconnect considered connected to be
I really don't want lightning to fry my TV.
The AC is just something convent for a ground, I guess.
They told me that the 3 prong plug is what they are using for the ground.
I told them that because my sister lost 2 tvs to lightning that the 3 prong
plug won't fly.
I really don't know what they should but I know that the 3 prong plug didn't
protect my sister's tv.
Your grounding electrode conductor and main bonding jumper should be in the
service disconnect enclosure. That is exactly where the bonding to the
satellite should go It just needs to be brought inside the enclosure to the
ground bus bar.
Just read the section - it answers all your questions.
Basically, you run a No.14 to the service if it is not more than 20 feet
away or you install a separate grounding electrode. The no. 14 is bonded to
the service disconnect on the outside using a small split bolt stud. If you
think the No. 14 is subject to damage use a No. 6 or even a No. 4 solid
copper and staple along the way.
You can use a separate ground rod , but if it is less than 20 feet from the
service ground rod they must be bonded together. I would do this using a
direct buried No. 6 solid copper bonding jumper. This is not the least
expensive way nor is it required. But remember the NEC is a minimum safety
standard. There is no problem in being better than the NEC.
In a new installation the electrician would have had to install one of
the means in 250.94 of the US NEC to provide a place to bond other
systems such as your receiving station antenna. That is what it is by
the way rather than a cable television system. The US NEC allows the
grounding conductor to run inside or outside but it must connect to the
service equipment, electrical service Grounding Electrode Conductor
(GEC), an electrical service grounding electrode, the accessible means
covered in 250.94, or to a separate grounding electrode that is then
bonded to the electrical service grounding electrode system. The
sections that would seem to apply are quoted below. Attaching the
grounding conductor to the Air Conditioning disconnect is not an
acceptable method of grounding the antenna structure or the discharge
unit for the lead in.
"250.94 Bonding for Other Systems.
An accessible means external to enclosures for connecting intersystem
bonding and grounding conductors shall be provided at the service
equipment and at the disconnecting means for any additional buildings or
structures by at least one of the following means:
(1) Exposed nonflexible metallic raceways
(2) Exposed grounding electrode conductor
(3) Approved means for the external connection of a copper or other
corrosion-resistant bonding or grounding conductor to the grounded
raceway or equipment."
Masts and metal structures supporting antennas shall be grounded in
accordance with 810.21.
810.21 Grounding Conductors -- Receiving Stations.
Grounding conductors shall comply with 810.21(A) through (J).
(A) Material. The grounding conductor shall be of copper, aluminum,
copper-clad steel, bronze, or similar corrosion-resistant material.
Aluminum or copper-clad aluminum grounding conductors shall not be used
where in direct contact with masonry or the earth or where subject to
corrosive conditions. Where used outside, aluminum or copper-clad
aluminum shall not be installed within 450 mm (18 in.) of the earth.
(B) Insulation. Insulation on grounding conductors shall not be required.
(C) Supports. The grounding conductors shall be securely fastened in
place and shall be permitted to be directly attached to the surface
wired over without the use of insulating supports.
Exception: Where proper support cannot be provided, the size of the
grounding conductors shall be increased proportionately.
(D) Mechanical Protection. The grounding conductor shall be protected
where exposed to physical damage, or the size of the grounding
conductors shall be increased proportionately to compensate for the lack
of protection. Where the grounding conductor is run in a metal raceway,
both ends of the raceway shall be bonded to the grounding conductor or
to the same terminal or electrode to which the grounding conductor is
(E) Run in Straight Line. The grounding conductor for an antenna mast or
antenna discharge unit shall be run in as straight a line as practicable
from the mast or discharge unit to the grounding electrode.
(F) Electrode. The grounding conductor shall be connected as follows:
(1) To the nearest accessible location on the following:
a. The building or structure grounding electrode system as covered in
b. The grounded interior metal water piping systems, within 1.52 m (5
ft) from its point of entrance to the building, as covered in 250.52
c. The power service accessible means external to the building, as
covered in 250.94
d. The metallic power service raceway
e. The service equipment enclosure, or
f. The grounding electrode conductor or the grounding electrode
conductor metal enclosures; or
(G) Inside or Outside Building. The grounding conductor shall be
permitted to be run either inside or outside the building.
(H) Size. The grounding conductor shall not be smaller than 10 AWG
copper, 8 AWG aluminum, or 17 AWG copper-clad steel or bronze.
(I) Common Ground. A single grounding conductor shall be permitted for
both protective and operating purposes.
(J) Bonding of Electrodes. A bonding jumper not smaller than 6 AWG
copper or equivalent shall be connected between the radio and television
equipment grounding electrode and the power grounding electrode system
at the building or structure served where separate electrodes are used."
Copyright 2002 National Fire Protection Association.
As I indicated in my previous post, I doubt that the dish installers have
the expertise to address the grounding/bonding as evidenced by the manner of
their work so far.
If I were in your shoes I would do the following (as I suggested earlier) in
the following order:
1) Read article 810 of the NEC, and then call your local electrical
inspector asking for an evaluation of the work so far.
2) Contact an electrician, or other qualified electrical professional to
advise/correctly complete the installation.
3) Although the NEC allows the Grounding Wire to be run inside/outside the
structure, I would run it, and the Bonding of Electrode where required, from
the dish outside the structure as straight as possible directly to the
ground. From there direct buried to the service location. It isn't necessary
to enter the service equipment to make the connection, but is one of the
permissible methods. If present I would connect to the Grounding Electrode
Conductor outside the building with an exothermic, or other approved method.
You could drive a ground rod and bond it as well, but I believe the direct
buried conductor would be far more effective than a driven ground rod.
Running the grounding/bonding conductor inside the home before connecting to
the electrical system grounding grid is asking for trouble in an area where
lightning activity is likely.
If the installation does not meet NEC requirements (as
others have suggested), then installer can be held accountable
to repair an installation at his cost. But NEC only addresses
human safety issues. You are concerned also about transistor
safety - from lightning. Why was your sister's TV damaged?
Lightning sought earth ground. Best path to earth was through
I must make assumptions about your installation. For
example, dish is atop the roof. For lightning protection, a
direct ground wire from dish is earth ground rod is necessary
- as if the dish were a lightning rod. Lightning seeking the
electrically best path into earth would prefer a shorter path
(assuming well earthed ground rod) rather than the longer path
Coax is more than 20 feet down from roof. Therefore the
coax must route to and enter building at service entrance so
that coax grounding block (available everywhere from Home
Depot to Radio Shack) makes a less than 10 foot connect to AC
electric and telephone earth ground rod - the building's
central earth ground. This connection serves two masters.
First, meets NEC requirements for human safety. Second,
earths incoming transients before getting near to TV.
Think of the installation as if it were two structures. One
is your building; other is the dish. Each therefore must have
its own central earth ground. That short 14 AWG (or larger)
ground wire from dish to dedicated ground rod would be the
dish's connection to its central earth ground. Same concept
is demonstrated in this figure where building and tower are
each earthed as if separate structures:
Notice that both central earth grounds are connected. That
makes the earthing system that much more effective. Dish's
ground rod connected to building's ground by a buried, bare
copper wire. How good does you earthing system need be? A
function defined by neighborhood experience and geological
conditions. But protection is defined by what people forget
because they don't see it - the earthing system.
Interconnecting those ground rods by a buried copper wire can
only enhance the earthing system significantly - if
neighborhood history recommends it.
NEC requires telephone and cable to connect less than 20
feet to the same AC electric earth ground. That for human
safety. You want to exceed NEC requirements to protect
transistors. Therefore connections to a central earth ground
(by hardwire or via surge protector) must be less than 10
feet. Not ten feet to main disconnect. Ten feet to main
disconnect AND additional feet to earth ground. That earth
ground (and connections to it) determines probability of
Recently had a long discussion with two CATV installers. As
I explained this, the installer was having revelations. They
had 'sort of' taught him this, but it was not understood. For
example, he was running a CATV wire directly into second floor
TV. Wrong. First the CATV wire must drop down to central
earth ground so that earthing connection (from ground block to
earthing rod) is less than 10 foot. Only then does CATV wire
rise back up to enter second floor. Furthermore, the dropping
CATV wire must be separated from the rising wire - so as to
not induce transients on wire after ground connection. He was
installing CATV wire correctly according to NEC requirements -
a 20 foot connection to earth. But for transient protection,
cable must first drop to make an earth ground connection.
They connected your dish to some earth ground? Some
installers connect to a water faucet. Look at that
connection. How many feet from faucet to earth ground? That
length increases with each copper pipe solder joint and each
90 degree bend. IOW that faucet connection is not an earth
ground from the perspective of transients. And it is no
longer acceptable as an earth ground from perspective of NEC.
That third prong on an AC electric plug is also not an earth
ground - for same reasons. And yet many cable installers will
deny this. All utilities (including dish cable) should enter
building at a common service entrance so that all can be
earthed, less than 10 foot, to a single point earth ground.
Those are the concepts. Hope they are appropriate for your