Motorola SC 4812ET RF Hardware Installation Manual page 35

Cable Size Resistance per 1,000 ft @ 50Deg C
2/0 AWG
4/0 AWG
NOTE
– 3.65 m (12 ft.) is the length of the # 2/0 AWG DC Power Cable supplied with the Power Cabinet.
– If a custom cable is used, 610 mm (2 ft.) should be reserved at both ends to allow for the distance from the
edge of the cabinet to the power terminals.
Apr 2001
SC
TM
V02.03
– Adequate ventilation must be available to dissipate heat loads of
7,500 Watts (25,600 Btu / hr) for the RF Cabinet and 3,000 Watts
(10,300 Btu / hr) for the Power Cabinet (a total of 10,500 Watts;
35,900 Btu / hr), and maintain a maximum temperature of no
greater than 50 Deg C (122 Deg
– The AC meter and main disconnect should not be mounted to either
cabinet.
– Locations should be selected that will minimize accidental or
intentional vandalism. Do not select a location that is, or may be,
subject to submersion (i.e. diversion channels, sub–basements, etc).
While the RF and Power Cabinet are well insulated from the
environment, they will not tolerate submersion.
– There should be adequate clearance through doors and passageways
to allow movement of the cabinet from the delivery area to the
installation site.
– Verify, prior to final site selection, the availability and accessibility
to good grounding (ground system resistance must be less than 10
Ohms, with 5 Ohms or less being the goal; see "Recommended
Documentation" for Grounding Guidelines), RF cabling, Telco
wiring, and 208–240 VAC power.
– There should be adequate space available for the future addition of
expansion or optional equipment.
– The location of an AC power pedestal to mount the AC meter, main
breaker, generator plug, etc. (if necessary), is at the installers option.
– Every effort should be made to minimize the separation distance
between the RF and Power Cabinet (see Table 2-1) for maximum
cable length between cabinets
Table 2-1: DC Cabling Size – Maximum Cable Length
mW (THHN Cable)
96.8 (Superflex)
54 (Duraflex)
4812ET RF and Power Cabinet Hardware Installation Manual
DRAFT
Site Preparation
F)
.
Maximum Cable Length
(Max Total Voltage Drop  0.4V,
assumes 90A per cable)
6.7 m (22 ft)
12.5 m (41 ft)
– continued
2
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