JLG 800S Service Manual - Manual (Page 248)

SECTION 4 - BOOM & PLATFORM
4-32 – JLG Lift – 3121139
STEP 2: CALIBRATING THE PLATFORM LEVEL
SENSORS (FOR PLATFORM SOFTWARE PRIOR TO
VERSION P3.4)
1. Put machine into “Ground Mode”.
2. Start machine and plug in Analyzer.
3. Manually level the platform with the switch on the
MTB.
4. Go to the “Access Level 2” screen.
5. Enter “33271” to get into Access Level 1 mode.
6. Go to the “Calibrations” menu and hit ENTER.
7. Use RIGHT ARROW go to “Plat. Leveling” screen.
8. Hit ENTER. “Calibrate?” prompt should appear.
9. Hit ENTER again to calibrate level sensors.
10. When calibration has been successful “Cal. Com-
plete” should appear.
11. Cycle power to the machine.
STEP 3: BLEEDING THE PLATFORM VALVES
Start up the machine and exercise the following platform
functions (from the ground) eight (8) to ten (10) times for 5
seconds in each direction.
Basket Rotate
Basket Level
Jib U/D (if configured)
STEP 4: CALIBRATING THE PLATFORM LEVEL UP
AND DOWN VALVE CRACKPOINTS
NOTE: Since the valve position which allows minimum oil
flow (crackpoint) is dependent on the oil pressure,
verify the proper stand-by pressure as outlined in
Section 5.3 prior to setting the crackpoints.
1. Put machine into “Ground Mode”.
2. Start machine and plug in Analyzer.
3. Go to the “Access Level 2” screen.
4. Enter “33271” to get into Access Level 1 mode.
5. Go to the “Calibrations” menu and hit ENTER.
6. Go to the “Basket U Crkpt” Screen. Hit ENTER.
7. “Calibrate?” prompt should appear. Hit ENTER
again.
8. You will hear engine go to 1800 rpm.
9. Using UP ARROW, increase the value until you see
the basket up movement. (Typically from 275 – 425).
10. Hit ENTER again. “Cal. Complete” message should
appear
11. Engine should again return to idle.
12. Hit ESC should return to “Basket U Crkpt” screen.
13. Hit RIGHT ARROW to get to the “Basket D Crkpt”
screen. Hit ENTER.
14. “Calibrate?” prompt should appear. Hit ENTER
again.
15. You will hear engine go to 1800 rpm.
16. Using UP ARROW, increase the value until you see
the basket down movement. (Typically from 275 –
425).
17. Hit ENTER again. “Cal. Complete” message should
appear.
18. Engine should again return to idle.
19. Hit ESC to exit.
20. Cycle power to the machine.
21. The preceding steps will provide acceptable crack-
point settings for the majority of machines. However,
if the operator can feel small jolts in the platform
from the valve opening during a leveling operation,
the crackpoint is likely too high for this machine. A
high crackpoint may also lead to "over-leveling",
causing the platform to drift beyond the set point. An
example of this would be the platform tilting too far
backwards during a Lift Up operation. Therefore,
use the following guidelines to evaluate whether fur-
ther crackpoint adjustment is required.
a. Telescope the machine halfway.
b. Perform Lift Up. If the basket leans backward
(over compensates), the Level Down crackpoint
is too high. If the basket leans forward or a BAS-
KET LEVELING SYSTEM TIMEOUT fault occurs,
the Level Down crackpoint is too low.
c. Perform Lift Down. If the basket leans forward
(over compensates), the Level Up crackpoint is
too high. If the basket leans backwards or the
Tilt Cutout Alarm comes on, the Level Up crack-
point is too low.