HANDBOOK REQUIREMENTS - Central Maine Power Company

Notes:
1. Aluminum electrodes are NOT permitted.
2. Per NEC Section 250.56, where a single made electrode
(5, 6 or 7 above) exceeds 25 ohms resistance to ground,
an additional electrode consisting of any one of 2
through 8 must be utilized. When this additional
electrode is a made electrode (5 ,6 or 7), it shall be
installed at least 6 feet away from, and bonded together
with, the first electrode. Although the NEC requires a
minimum separation of only 6 feet, the Company highly
recommends a minimum separation of 16 feet (between
8 foot ground rods) in order to maximize the paralleling
effectiveness.
For much of Central Maine Power Company’s service
territory, meeting the “25 ohms or less” requirement is
highly unlikely; therefore, installation of an additional
electrode should be anticipated.
It is the responsibility
of the customer/electrician to verify the 25 ohms, or
less, resistance and/or install the additional
electrode.
3. See NEC Sections 250.50 thru 250.70 for further details
on grounding electrode systems.
702. BONDING
To prevent any potential differences from occurring
between them, all of the grounding electrodes listed in paragraph
701, as well as, CATV, communications or any other system
grounding electrodes that are available on the premises, shall be
bonded together. Intersystem bonding shall be installed in
accordance with NEC 250.94 and shall have the capacity for at
least 3 intersystem bonding conductors. It is the
responsibility of
the customer/electrician to ensure intersystem bonding
provisions are provided. In the case where
the grounding
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