JLG 800A_AJ Service Manual - Manual (Page 261)

SECTION 4 - BOOM & PLATFORM
3120858 – JLG Lift – 4-47
4.16 LOAD SENSING SYSTEM MACHINES
BUILT S/N 62045 TO 67883
Calibration
1. Select Access Level from Main Menu.
2. Enter 33217.
3. Select Machine Setup from Main Menu.
4. Select Option #1 under the Load menu.
5. Select Calibrations from Main Menu.
6. Select Load Sensor from the Calibrations Menu.
7. With no weight in the basket press Enter.
8. When prompted by analyzer place 500 LBS. in the
basket and press Enter.
9. When prompted by the analyzer, remove the weight.
10. System is now Calibrated.
4.17 FOOT SWITCH ADJUSTMENT
Adjust so that functions will operate when pedal is at cen-
ter of travel. If switch operates within last 1/4 in. (6.35 mm)
of travel, top or bottom, it should be adjusted.
4.18 UPRIGHT MONITORING SYSTEM
The UMS provides a visual and audible warning to the
operator when the limits of the upright assembly align-
ment have been reached. In addition, the UMS will not
allow the tower boom to be lowered when the upright
assembly is misaligned in a direction oriented away from
the work platform.
Re-Synchronizing Upright
A pull type control valve allows the operator to adjust the
upright level cylinder if the upright is not 90° (vertical) rela-
tive to the chassis (Refer to Figure 4-27.). This valve is
located in the tank compartment area.
Perform the following steps with the aid of an assistant:
1. Turn the key switch to the ground control position.
2. Start the engine.
3. Pull and hold the red relevel knob located next to the
main control valve. Refer to Figure 4-26.
4. Raise the tower boom 6 feet (1.8 m).
5. Release the red relevel knob.
6. Lower the tower boom fully and continue to hold
down the switch to Tower Down for an additional 20
seconds.
7. Repeat steps 3 thru 6 as necessary until the upright
is 90° (vertical) relative to the chassis.
Figure 4-25. Load Sensing Transducer
Figure 4-26. Releveling Valve