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 mounted on the car is allowed. It shall have at least one pinion, one rack, and two back-up
rollers. Driving machines located within the car shall be fully enclosed and locked.
9.6.9 Driving-Machine Terminal-Stopping Switches
The normal terminal stopping devices for winding drum machines are required to consist of
switches located in the hoistway or on the car, and operated by the movement of the car. Where
the normal terminal stopping switches are located on operated by the driving machine, they
should be inspected and where possible, operated by hand to determine that the switch and its
contacts are in proper operating condition. Determine that the switch contacts, particularly any
motor mainline contacts provided, are not burned or worn excessively, and that all gears, chains,
or wire ropes and pulleys provided for their operation operate as intended and are not worn
excessively. Close the mainline switch and run the empty car to each landing until stopped by
the machine terminal stopping switch. Note whether the switch stops the car near the landing.
Determine that at the bottom terminal landing with no load in the car, allowance has been made
for the greater slide that could occur when rated load is in the car.
9.6.10 Slack-Rope Device
Slack-rope devices are required only for winding-drum machines. The device is arranged to
monitor the loss of tension in the hoistway ropes. Most are located at the hoist rope termination,
however, some devices are located at the hoist machine. Electric switches used with slack-rope
devices should be of the enclosed, manually reset type and should be tested by tripping the device
by hand with the machine running. This should stop the car. Where the slack-rope device cannot
be operated by hand, test at intervals of not longer than 12 months by lowering the car onto a
suitable support or supports placed in the pit. Determine that the tension in the hoisting ropes
decreases sufficiently to operate the device and stop the machine. Determine that there is no
interference with the free and complete movement of the slack-rope device for the hoisting ropes
and the detector bars are set as close as possible to the driving-machine drum in order to open the
switch with a minimum of slack rope.
9.6.11 Normal And Final Terminal Stopping Switches
Normal and final stopping switches are required in some cases; the normal terminal stopping
switches are located in the machine room and operated by a rope, tape, or chain attached to the
car. Switches on rack and pinion drives are required to be located on the car. These switches
should be examined as previously outlined.
9.6.12.1 Inspection Made with Power On. Close the mainline switch and proceed. Have the
hoist operated in each direction, making frequent stops. Observe if there is any excessive play or
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