Originally Posted By: bbadger
This post was automatically imported from our archived forum.
Hi all.
Regardless of what the instructions may show just driving a ground rod is not enough.
You may simply connect it to the buildings existing grounding electrodes or you may add a rod at the dish or antenna but it still must be bonded to the buildings electrodes.
That was the short answer, for those that are interested here is the NEC answer.
It is a lot of code and I made the parts relative to the question blue, however all of this info has to do with dishes and antennas
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ARTICLE 810 Radio and Television Equipment
I. General
810.1 Scope.
This article covers antenna systems for radio and television receiving equipment, amateur radio transmitting and receiving equipment, and certain features of transmitter safety. This article covers antennas such as multi-element, vertical rod, and dish, and also covers the wiring and cabling that connects them to equipment. This article does not cover equipment and antennas used for coupling carrier current to power line conductors.
<SNIP>
810.15 Grounding.
Masts and metal structures supporting antennas shall be grounded in accordance with 810.21.
<SNIP>
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 connected.
(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 250.50
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
(2)If the building or structure served has no grounding means, as described in 810.21(F)(1), to any one of the individual electrodes described in 250.52; or
(3)If the building or structure served has no grounding means, as described in 810.21(F)(1) or (F)(2), to an effectively grounded metal structure or to any of the individual electrodes described in 250.52.
(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.
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Bob Badger
Electrical Construction & Maintenance
Moderator at ECN