Published 08-25-09, Control # 077-04 5-13
RT9130E SERVICE MANUAL HOIST AND COUNTERWEIGHT
THIRD WRAP INDICATOR
Description
The third wrap indicator (Figure 5-4) is installed to give the
operator an indication that the wire rope is down to the last
three wraps on the hoist drum and no more rope should be
reeled out. In addition to the warning light in the cab, a
lockout valve is actuated to stop hoist down operation.
Maintenance
Removal
1. Disconnect third wrap indicator from power by removing
fuses F17 and F16. Tape over the sockets of the
removed fuses.
2. Remove the control unit cover. Tag and disconnect the
wiring to the limit switch.
3. Loosen and remove the outside nut and washer
securing the threaded rod to the hoist mounting.
4. Loosen and back off the inside nut on the threaded rod.
5. Loosen and back off the nut holding the sensor shaft in
place against the side plate.
6. Unscrew the threaded rod from the sensor shaft.
7. While removing the nuts and remaining washer from the
inside end of the threaded rod, pull the threaded rod out
through the hoist housing.
8. Remove the setscrews and slide the limit switch bracket
and limit switch, actuating cam, arm (with roller), spring,
and spring holder collar from the sensor shaft.
9. Loosen and remove the capscrew and washer securing
the sensor shaft to the hoist housing.
Installation
NOTE: All fasteners must be treated with medium strength
threadlocking adhesive sealant and primer.
1. Install the capscrew and washer to secure the sensor
shaft to the hoist housing. Torque the capscrew 117 to
127 Nm (86 to 94 foot-pounds).
NOTE: Apply antiseize grease to inside of indicator arm
before installing onto sensor shaft.
NOTE: Position center of roller approximately 7.6 cm (3 in)
from the inside flange of the hoist drum such that
the roller drops to the drum after the fourth wrap is
unwound from the drum.
NOTE: Adjust actuating cam and/or limit switch collar such
that switch plunger drops into notch when roller
drops to bare hoist drum.
NOTE: Adjust spring holder collar such that spring applies
ample pressure to arm.
2. Slide spring holder collar, spring, arm (with roller),
actuating cam, limit switch bracket and limit switch onto
the sensor shaft. Secure with the related setscrews.
3. Install the threaded rod through the opening in the hoist
housing and thread the washer and two nuts onto the
rod.
4. Screw the threaded rod into the sensor shaft.
5. Tighten the nut to hold the sensor shaft to the side plate.
6. Tighten the nut securing the threaded rod to the hoist
housing.
7. Install the remaining washer and nut onto the outside
end of the threaded rod. Adjust so the centerline of the
roller is 3.0 inches (7.6 cm) from the inside face of the
nearby side plate. Torque the set screws in the limit
switch bracket, actuating cam, arm (with roller), and
spring holder to 10-13 inch-pounds (1.1 to 1.5 Nm after
final adjustment.
8. Torque the three nuts 117 to 127 Nm (86 to 94 foot-
pounds). Ensure the centerline of the roller is still 3.0
inches (7.6 cm) from the inside face of the nearby side
plate.
9. Reconnect the wires to the third wrap indicator limit
switch and reinstall the control unit cover.
10. Restore power to third wrap indicator by installing fuses
F17 and F16.
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