JLG 120-SXJ ANSI Service Manual - Manual (Page 69)

SECTION 4 - BOOM & PLATFORM
3121105 – JLG Lift – 4-17
Boom Angle Sensor Adjustment
1. With the platform level, the boom fully retracted and
at 45 (+/- 1) degrees elevation, measure the DC
voltage at TP5 on the Load Radius Circuit Card.
2. Loosen the three screws securing the sensor to the
box and rotate the sensor until 7.1 (+/- 0.1) Volts DC
is measured at TP5. Tighten the screws on the sen-
sor.
3. Return the boom to horizontal.
Radius Adjustment and Display Lights
Setting Procedure
1. On the Load Radius Circuit Card, measure TP11 and
adjust potentiometer P6 for a reading of 0.0 Volts
DC.
2. On the Load Radius Circuit Card, measure TP8 and
adjust potentiometer P2 for a reading of 2.128 Volts
DC.
3. On the Load Radius Circuit Card, measure TP9 and
adjust potentiometer P3 for a reading of 2.548 Volts
DC.
4. Telescope the boom until the leading edge of the
yellow marking tape is exposed from the mid boom.
Adjust potentiometer P2 until the yellow light just
turns on and the blue light turns off.
5. Telescope the boom until the leading edge of the red
marking tape is exposed from the mid boom. Adjust
potentiometer P3 until the red light just turns on and
the yellow light turns off.
6. Extend the boom until the red tape is approximately
6 inches out of the base boom. Adjust P4 until the
amber LED (DS2) on the Load Moment Circuit card
goes out. This determines the length of the boom
(critical length) where the lift down speed limiter is
turned on.