PairGain 150-458-100-05, Руководство пользователя

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150-458-100-05 Installation
HRE-458 List 1, List 1B, and List 2 February 23, 2000 11
G
ROUNDING
The HRE-458 requires a resistance of 25
Ω
or less to ground as measured with a megger-type Ohmmeter.
Have the following equipment ready before you begin the procedure:
• One bullet bond
• One ground rod for pole mounted enclosures (may require more than one rod)
• One megger-type Ohmmeter
• 6 American Wire Gauge (AWG) cable
The 8 MIL aluminum shield around the cable stub is connected to the enclosure’s ground by attaching it to the
card cage mounting bracket with a braided shield ground wire as shown in
Figure 9 on page 22 . The purpose of
the ground wire is to connect the stub aluminum shield to the enclosure ground lug when the stub’s shield is not
bonded to the shield of the main feeder cable. The wire may need to be temporarily removed from the enclosure
ground lug when troubleshooting ground faults. This is accomplished by removing the screw that secures the
braided ground strap to the mounting bracket on the card cage.
Grounding a Pole Mounted Enclosure
Use the following procedure to ground a pole or pedestal-mounted enclosure (see Figure 5 ).
1 Bond the main cable shield through the splice case using bullet bond.
2 Drive the ground rod into the ground near the enclosure location.
The ground wire should be reconnected to the card cage bracket after completing the ground
fault test. This insures that the stub’s shield is properly grounded which is required to reduce
the effects of shield corrosion and lightning damage.
The screen divider on the stub is an insulated floating divider separating the pairs. DO NOT
GROUND THIS SCREEN DIVIDER. Doing so could result in degraded performance.
Make sure you ground the HRE-
458
before splicing the cable stub into the main cable. This
grounding method (or an accepted local grounding method) must be in effect at all times to
safeguard personnel.
If the HRE-
458
is improperly grounded, the Lightning Protection Unit (LPU) surge arrestors will
not work and the enclosure will be unprotected.