Alternative Grounding Method; Local Power Source Wire Run - ADTRAN Total Access 372 Installation And Maintenance Manual

Alternative Grounding Method

The following is an alternative grounding method if MGN is not available.
Article 800‐11c of the National Electrical Code (NEC) states for the purpose of grounding the
point of entry for communications wiring and cables should be within 20 feet (6.1 meters) of
the electrical service entry point. Where this is impractical, a separate grounding electrode
should be installed in compliance with Article 800‐40‐(b)(3) and bonded in compliance with
Article 800‐40(c) and (d).
Briefly stated:
• A copper clad steel ground rod should be driven into the earth at least 8 feet (2.4 meters)
• An Earth Resistance Megger Test Set is used to determine the resistance of the earth
• The secondary electrode must be spaced at least 8 feet (2.4 meters) from the primary
• The 12 AWG ground wire should be connected to the ground rod with a UL Listed ground

Local Power Source Wire Run

!
WARNING
• Before making any power connections to this equipment, verify the power
is off (fuse removed/breaker tripped).
• This equipment should only be operated from the type of certified/listed
power supply recommended by the manufacturer.
!
CAUTION
• Use caution when routing wires and cables. Avoid severe bending and
routing over sharp edges. Use grommet material when possible to avoid
wear on cable insulation.
• To reduce the risk of fire, use minimum no. 26 AWG telecommunications
line cord.
Installation of the Limited Power Source (LPS) will be dictated by on‐site conditions and local
telephone company practices. Refer to Figure 10 on page 22 and the following steps to
complete the installation.
1. Install the Local Power Source (LPS) wire run from the SBU ONT to the connector of the
2. If necessary, tie wrap both the 12 AWG ground wire and LPS wire run to the buried fiber
61287722G1-5B
deep.
electrode. The NEC requires this ground rod conduction to earth to be no more than 25
ohms of resistance. If 25 ohms cannot be achieved with a single electrode (ground rod), a
secondary electrode must be used and bonded to the primary electrode using a 12 AWG
minimum copper ground wire.
electrode.
clamp.
LPS via the customer provided PVC conduit (or method used by your local telephone
company). For power, ADTRAN recommends using 16 AWG wire at a maximum of 100
feet (30.5 meters). For alarm signals, ADTRAN recommends using 24 AWG wire. Do not
plug in the UPS green connector at this time. This will be done after the subscriber's wire/
cables are terminated during turn‐up and testing.
drop cable riser conduit.
Installation
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