MIL-HDBK-1025/10
b. Ground wires on distribution wood poles should be protected with wood molding for
the entire working length of the pole and protected to prevent guy wires from cutting the ground
wires. The entire working length of the pole is from the point where ground wire terminates near
the top of the pole to 1.5 meters (5 feet) below the lowest crossarm or bracket, and from the
ground line to 2.5 meters (8 feet) above the ground line.
c. Never cut an overhead ground wire or neutral wires of any kind because of the need for
line or equipment replacement, unless specifically instructed by your supervisor to do so. Also,
avoid opening a joint in such a wire without first bridging the joint with wire of a suitable size.
7.10.3.2 Common Neutral Systems. Fuses of all transformers should be opened before
work can be done on a transformer bank where the grounded neutral wire is used for both
primary and secondary neutrals. The connections from the transformer to the grounded neutral
should be made before the connection from the transformer to the phase wire is made. The
connection from the transformer to the grounded neutral wire should never be disconnected while
the transformer is energized.
7.10.3.3 Protective Grounding Equipment. Protective grounding equipment should be
maintained in good condition and should be inspected prior to each use. Use only approved
screw-type ground clamps. Grounding equipment should connected to ground point first, then to
the item to be grounded. (See Table 21.)
7.10.4 Handling and Stringing Guidance. ANSI/IEEE 524, Guide to the Installation
of Overhead Transmission Line Conductors, provides general recommendations on the methods,
equipment, and tools used for the stringing of overhead line conductors and ground wires. The
following safety precautions are mandatory.
7.10.4.1 Reels. Adequate braking should be used to stop all payout reels. Personnel
should not otherwise touch or attempt to stop the revolving reel.
7.10.4.2 Conductors. The inside end of the coil wire, where accessible, should be
securely fastened to the reel to prevent the wire from getting loose when the wire has been played
out. If the inside end of the coil cannot be secured, a tail rope should be fastened securely to the
wire before the end is reached to prevent its getting loose.
7.10.4.3 Conductor Grounding. Bond and ground all stringing equipment, such as reel
stands, trailers, pullers, or tensioners. (See Figure 6 and Table 28.)
7.10.5 Primary Line Installation. Lines should be strung to clear the ground by an
amount not less than that specified in the rules of the NESC. These minimums depend upon
whether the line is above a street (consider its street traffic classification), above a pedestrian way,
or over or near other structures. Wire and guys that are being strung should be kept clear of any
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