the systems are bonded together below grade. The combined resistance of
separate systems may be used to meet the required resistance, but the
specified number of electrodes shall be provided.
3.11.4
Medium-Voltage Preassembled Cable Test
**************************************************************************
NOTE: If the installation is tapping a new feeder
to an existing feeder using a "T" splice, modify the
paragraph to indicate that when existing cable
cannot be readily disconnected, the system should
only be tested to the lower (after installation)
voltage. Delete the test if no cable is installed
in the project.
**************************************************************************
After installation, prior to connection to an existing system, and before
the operating test, the medium-voltage preassembled cable system shall be
given a high potential test. Direct-current voltage shall be applied on
each phase conductor of the system by connecting conductors at one terminal
and connecting grounds or metallic shieldings or sheaths of the cable at
the other terminal for each test. Prior to the test, the cables shall be
isolated by opening applicable protective devices and disconnecting
equipment. The method, voltage, length of time, and other characteristics
of the test for initial installation shall be in accordance with NEMA WC 74
for the particular type of cable installed, and shall not exceed the
recommendations of IEEE Std 404 for cable joints unless the cable and
accessory manufacturers indicate higher voltages are acceptable for
testing. Should any cable fail due to a weakness of conductor insulation
or due to defects or injuries incidental to the installation or because of
improper installation of cable, cable joints, terminations, or other
connections, the Contractor shall make necessary repairs or replace cables
as directed. Repaired or replaced cables shall be retested.
3.11.5
Sag and Tension Test
The Contracting Officer shall be given prior notice of the time schedule
for stringing conductors or cables serving overhead medium-voltage circuits
and reserves the right to witness the procedures used for ascertaining that
initial stringing sags and tensions are in compliance with requirements for
the applicable loading district and cable weight.
3.11.6
Low-Voltage Cable Test
**************************************************************************
NOTE: The insulation resistance test (dielectric
test) value is based on the recommendation contained
in IEEE Std 525. Delete the cable test if no low
voltage cables are in the project.
**************************************************************************
For underground secondary or service laterals from overhead lines, the
low-voltage cable, complete with splices, shall be tested for insulation
resistance after the cables are installed, in their final configuration,
ready for connection to the equipment, and prior to energization. The test
voltage shall be 500 volts dc, applied for one minute between each
conductor and ground and between all possible combinations of conductors in
the same trench, duct, or cable, with other conductors in the same trench,
duct, or conduit. The minimum value of insulation shall be:
SECTION 16370A
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