Home Antenna Wiring


grnd clamp
         Grounding Clamps
     Antenna Discharge Unit

NEC Article 810 Radio and Television Equipment Summary

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.

Article 810 covers wiring requirements for television and radio receiving equipment,
specifically including digital satellite receiving equipment for television signals, and
wiring for amateur radio equipment.

810.3 Other Articles
Wiring from the source of power to and between devices connected to the interior wiring
system shall comply with Chapters 1 through 4 other than as modified by Parts I and II of
Article 640. Wiring for audio signal processing, amplification, and reproduction equipment
shall comply with Article 640.
Coaxial cables that connect antennas to equipment shall comply with Article 820.

810.4 Community Television Antenna
The antenna shall comply with this article. The distribution system shall comply with

Article 820.

810.15 Grounding
Masts and metal structures supporting antennas shall be grounded in accordance with 810.21.

810.16 Size of Wire-Strung Antenna — Receiving Station
• Self-Supporting Antennas.
• Outdoor antennas, such as vertical rods, dishes, or dipole structures, shall be of corrosion-resistant materials and of strength suitable to withstand ice and wind loading conditions and shall be located well away from overhead conductors of electric light and power circuits of over 150 volts to ground, so as to avoid the possibility of the antenna or structure falling into or making accidental contact with such circuits.

810.18 Clearances - Receiving Stations
• (A) Outside of Buildings
• Lead-in conductors attached to buildings shall be installed so that they cannot swing
closer than 600 mm (2 ft) to the conductors of circuits of 250 volts or less between
conductors, or 3.0 m (10 ft) to the conductors of circuits of over 250 volts between
conductors, except that in the case of circuits not over 150 volts between conductors,
where all conductors involved are supported so as to ensure permanent separation, the
clearance shall be permitted to be reduced but shall not be less than 100 mm (4in.). The
clearance between lead-in conductors and any conductor forming a part of a lightning rod
system shall not be less than 1.8 m (6 ft) unless the bonding referred to in 250.60 is
accomplished. Underground conductors shall be separated at least 300 mm (12 in.) from
conductors of any light or power circuits or Class 1 circuits.

810.20 Antenna Discharge Units — Receiving Stations

A. Where Required
• Each conductor of a lead-in from an outdoor antenna shall be provided with a listed antenna discharge unit.

• Exception: Where the lead-in conductors are enclosed in a continuous metallic shield that
either is permanently and effectively grounded or is protected by an antenna discharge unit.

B. Location

• Antenna discharge units shall be located outside the building or inside the building between the point of entrance of the lead-in and the radio set or transformers and as near as practicable to the entrance of the conductors to the building.

810.21 Grounding Conductors - Receiving Stations

C. 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 (18in.) of the earth.

D. 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.

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.

810.21 Grounding Conductors - Receiving Stations (Continued)

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

F. Electrode
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
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

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.

return to top
2016 onestoneworks.com
Saint Augustine, Florida