Functional check, Calibration, Calibration potentiometers -46 – JLG 800A_AJ Service Manual User Manual
Page 260
SECTION 4 - BOOM & PLATFORM
4-46
– JLG Lift –
3120858
The display unit consists of three lights, an audio alarm,
and a test button. The green light signifies that the plat-
form load is within limits. The yellow light signifies that the
platform load is approaching an overload condition. The
red light signifies that the platform is overloaded. The
audio alarm beeps when the yellow light is lit and the plat-
form is approaching an overload condition. The alarm
sounds continuously when the platform is overloaded and
the red light is lit. The test button is used to test the audio
alarm and the warning lights
Functional Check
On a daily basis, perform a functional check of the system
by powering the platform control console and pressing
the test button on the display unit. This will test the warn-
ing lights and the buzzer. Every 3 months or quarterly, test
the function of system by placing a known weight in the
center of the platform as outlined under Calibration.
Calibration
NOTE: Calibration is only to be performed by a certified JLG
Service Technician.
1. With no load in the platform, turn on the platform
console box. The green light on the display unit
should activate. Press the test button to check the
alarm and indicator lights.
2. Attach a Digital Volt Meter (DVM), + lead to PL3/5
and the - lead to PL3/6. Adjust pot VR1 until zero (0)
value reading of 2.95 V shows on the DVM display.
3. Further calibration requires placing a weight of 215
± 10 kg (475 ± 20 pounds) in the center of the plat-
form left to right and 56 TO 59 cm (22 to 23 inches)
from the front of the platform to the center of the
weight.
4. Adjust pot VR6 until the yellow light and alarm acti-
vates (1.67 to 1.59 on the DVM display).
5. Final calibration requires placing a weight of 240 ±
10 kg (525 ± 20 pounds) in the center of the plat-
form and adjusting pot VR5 until the red light acti-
vates and the alarm sounds continuously (1.57 to
1.53 volts on the DVM display).
Figure 4-24. Calibration Potentiometers