standards and guidelines for communication sites - Radio And ...

SPECIAL GROUNDING (EARTHING) APPLICATIONS CHAPTER 4: EXTERNAL GROUNDING (EARTHING)
• Electrostatic discharge (ESD) precautions as defined in “Protecting Against Electrostatic Discharge
in Equipment Rooms and Dispatch Centers” on page C-1.
• External grounding (earthing) as follows:
• Grounding electrode system resistance design goal of 5 ohms or less. See “Type “B” Site -
Standard Duty” on page 4-45.
• Installation of all minimum required grounding electrode system components as described in
“External Building and Tower Ground Ring” on page 4-22.
• Bonding of all metallic objects as described in “Metallic Objects Requiring Bonding” on
page 4-67.
• Installation of radial grounding conductors as described in “Radial (Counterpoise) Grounding
Conductors” on page 4-24. Radial grounding conductors should be installed regardless if the
grounding electrode system resistance is 5 ohms or less without the radial grounding
conductors. A minimum of five radial grounding conductors should be installed.
9.1 m (30 ft) MINIMUM
BETWEEN TOWER AND
BUILDING (PREFERRED)
CABLE ENTRY PORT WITHIN
610 mm (2 ft) OF FLOOR
(PREFERRED)
ICE BRIDGE
SIDE VIEW OF BUILDING
NOTE: EGB AND COAX
GROUNDING NOT SHOWN.
FIGURE 4-58 GROUNDING ELECTRODE SYSTEM FOR DISPATCH CENTER CO-LOCATED WITH A
TOWER
4-82 68P81089E50-B 9/1/05