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 4.2.12 Hoistway Junction Box, Car Junction Box, And Traveling Cables
Hoistway and car junction boxes should be securely fastened with covers in place. Examine
the supporting means of the cable at the hoistway junction box and also the car junction box.
Traveling cables less than 100 ft. in length may be looped around a spool or other supporting
member and securely corded, wired, or taped to prevent loosening or separation of the loop. In
addition, the loop may be secured by clamps or other similar devices. Also see the National
Electrical Code, ANSI/NFPA No. 70, Section 620-41. Table 400.4, Note (6) of the National
Electrical Code requires that traveling cables exceeding 100 ft. between supports have steel
supporting members running through the center of the cable assembly. Examine the steel
supporting member, where attached to the hoistway or car junction box and determine that it is
securely fastened. The live load on the steel supporting fillers should hang in the direction of
tightening of the supporting bolt or other means of fastening and the dead end taped or clamped
to the live end. Examine particularly for any evidence of wear or breaks in the steel supporting
fillers which may damage the insulation of the conductors or cause the traveling cable to release,
causing strain or breakage to the conductors at the terminal lugs. Where a flexible wire mesh
automatic tightening device is used, examine the flexible wire mesh self-tightening grip to be
sure that it is securely fastened to its support at the hoistway or car junction box. Examine the
eye of the grip attached to the supporting member. When a double eye attachment is used, the
eyes should be attached, so that they share the load equally and do not exceed 15 degrees from
the axis of the vertical cable. There are basically three types of flexible wire mesh self-tightening
grips: closed type, split-laced type, and split-rod type. (See Figure 4-9). Examine the grip where
the eye is attached to the wire mesh section for any visible signs of wear or breakage. This point
is subject to damage because of flexing of cable. It is recommended that the lower section of the
grip be secured to the traveling cable to prevent triggering (total or partial relaxing of the grip)
and culminate in milking of the grip (slight movement of grip on the outer section of the
traveling cable). Examine for damage caused by the securing means. The triggering of the grip
may cause the cable to release, thereby placing strain or breakage on the individual conductors.
Milking of the grip may cause wear to the insulation of the traveling cable. Examine the
traveling cables for excessive twists or kinks; damage due to chafing; intertwining of multiple
cables; clearance from hoistway equipment such as buffers, plungers, brackets, beams, etc. All
electrical wiring needs to be checked. Many times wiring and conduit have become damaged
when working around the car top or hoistway. This must be constantly inspected to maintain a
safe environment.
4-15
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