User's Manual

Grounding Specifications
110 TDC-0971-011 CCU 100 and Repeater 100 Installation Guide
Proprietary and Confidential
2. Provide the second path by installing a 4/0 AWG down conductor from the MGB to
the ground rod or chemical ground rod. Use the water pipe main entrance if the
ground rod or chemical ground rod are not available. Do not use AC service panel
grounds.
3. If the Itron TCU / CCU equipment is located on the ground floor or in the basement,
the MGB may be connected directly to both building steel and the water main or
ground rod.
To ground one 4/0 AWG insulated down conductor and one existing
building lightning protection down conductor or building ground system
1. The first path is the installation of one 4/0 AWG insulated down conductor from the
roof top MGB bar to the ground rod or chemical ground rod. Use the water pipe main
entrance if the ground rod or chemical ground rod are not available. Do not use AC
service panel grounds.
2. Install the second path by bonding the roof top MGB bar with a 4/0 AWG insulated
conductor to the existing building lightning protection system or building ground
system down conductor.
3. If the Itron TCU / CCU equipment is located on the ground floor or in the basement,
the MGB can be connected directly to both the existing lightning protection or
building ground system and the water main or ground rod.
To ground one 4/0 AWG down conductor
Note Use this option when neither building steel nor a building lightning protection
or ground system is available at the Itron TCU / CCU equipment location.
1. Install one 4/0 AWG down conductor from the MGB bar on the roof to a MGB bar in
the basement.
2. Bond the basement MGB ground bar to ground by two separate paths.
3. Install two 4/0 AWG conductors from the MGB bar in the basement and terminate
each conductor to one of the following grounding options which are listed in the order
of preference.
Two different options must be selected for bonding the MGB bar to ground:
• Ground rod or chemical ground rod,
• Building grounding electrode system,
• Building steel (if available)
• Building cold water pipe main entrance.
If the Itron TCU / CCU equipment is located on the ground floor or in the basement, the
MGB may be connected directly to the two selected ground points without using a second
ground bar.