MIL-HDBK-1025/10
8.6.4.3 Underground Working Procedures. Avoid hazards by observing the following
procedures.
a. The secondary voltage of any transformer fed from a de-energized feeder cable should
be checked. The cable should be grounded on each side of the work location.
b. Neutral conductors should not be opened without the prior installation of suitable
bypass conductors.
c. Avoid moving energized underground cables. If cables must be moved, they will be
moved with extreme care to avoid damage to the cable insulation. Moving will be done only at
the discretion of the foreman in charge. Lead-sheathed underground cables will be moved only
when approved by the supervisor. Prior to moving energized electric underground cables, they
will be examined for any defects that might result in failure if the cable is moved. No energized
cable may be moved where such movement requires changing bends. All energized cables will be
handled with rubber gloves or hot-line tools as appropriate to the voltage level.
d. Before separating or connecting a dead-break type separable connector, the circuit
should be de-energized and tested dead utilizing the associated capacitive test point and an
approved test device. Only suitable live line tools will be utilized in separating or connecting
these separable connectors, unless the circuit is tested de-energized and grounded.
e. Avoid sparks in connecting or disconnecting cables, apparatus, or switching devices.
8.6.4.4 Grounding Switch Operation
WARNING
Before operating a primary grounding switch, the authorized operator
should make certain of the following:
a. Personnel are at the correct location.
b. The tags on the feeder cable and equipment in the vault or manhole bear the same
number as shown on single line drawings.
c. Network protectors are in the open position or, in the case of radial transformers,
which the secondary fuses have been removed and transformer secondaries are dead.
123
Previous Page
