ADCP-75-210 • Issue 1 • March 2007
Page 34
© 2007, ADC Telecommunications, Inc.
2.4.5 Fiber Requirements
Optical fibers are required at the site to provide the physical link between the RAN and the Hub.
In a typical installation, the identified fibers are broken out of a multi-fiber sheath and routed to
a splice box where they are spliced to pigtails connecting the main sheath to the RAN. The
actual fiber bundle location on the utility pole may vary per the agreed to attachment point.
Refer to Figure 25. The nylon cable connector on the rear of the RAN accommodates cables of
a diameter in the range .38 to .50 inches (.97 to 1.27 cm). For larger size cables, refer to
Section 1.6.2 on Page 9.
2.5 Installing a RAN Cabinet on a Wooden Utility Pole
Figure 25 shows the main components and their spatial placement in a typical NXD RAN pole
mount installation.
2.5.1 Site Requirements Unique to Pole Mounting Locations
If power lines are present at the top of the pole, spacing requirements applicable to the RF
cabling and any other hardware installed in the electric space must be considered. Per the
National Electrical Safety Code, vertical clearance at supports for primary-supply conductors
above other facilities is required to be 16 in. (40.64 cm) above neutrals and 40 in. (101.6 cm)
above communications (60 in. [152.4 cm] if above 8700V).
For supply conductors at voltages up to 8700 between conductors, the minimum horizontal
clearance provided by the NESC ANSI C2 is 12 in. (30.5 cm). For higher voltages, it is required
that .4 in. (10.2 mm) be added for every 1000V above 8700. Table 18 lists the required
clearances for some common high voltages.
This information is from the Standard Handbook for Electrical Engineers, 13th Edition,
McGraw Hill, Chapter 18, Section 151, Pages 18-65.
Table 18. Antenna Clearance vs. Voltage
VOLTAGE HORIZONTAL CLEARANCE
8700V 12.0 in. (30.5 cm)
15 kV 14.52 in. (36.9 cm)
28 kV 19.72 in. (50.1 cm)
38 kV 23.72 in. (60.2 cm)
