JLG 120-SXJ ANSI Service Manual - Manual (Page 50)

SECTION 3 - CHASSIS & TURNTABLE
3-22 – JLG Lift – 3121105
Dual Range
This Rotary Selector Controller is capable of providing
two, independently adjustable, maximum output ranges
with the same amount of knob travel. The Hi Range would
normally be adjusted for full flow (maximum function
speed) of the valve at full handle travel. The LO Range
would provide some portion of the Hi Range setting, pro-
viding reduced oil flow to the valve, with the knob at full
travel. LO Range provides the operator with excellent con-
trol of the proportional function with increased resolution
for precise maneuverability. Both outputs are linear
between the Threshold setting and their respective set-
ting. The Rotary Selector Controller is in the Hi Range
mode when 12 volts is applied to the (R) terminal. As a fail
safe, when system voltage is removed from the (R) termi-
nal, the Lo Range feature is active.
I.R.S (Integrated Ramp System)
This Rotary Selector Controller is calibrated to provide a
maximum ramp time of 3 seconds. This feature limits the
rate of change of the output, eliminating a jerky response
associated with sudden knob movements. Any change in
handle position will result in a smooth change in function
speed. The 3 seconds is measured between the Thresh-
old and Hi or LO range setting.
Adjustment Procedure
NOTE: The trimpot adjustment screws are multi turn
devices. No harm can come to the trimpot if it is
turned too much. The trimpot will "click" when the
wiper is at the end of the element. It may be neces-
sary to turn the adjustment screw several turns to
observe a change in the output.
1. Disconnect the output wire from the card to terminal
4. Install a volt-ohmmeter in series in this wire and
set the volt-ohmmeter to mA.
2. Turn on all power; engine does not need to be run-
ning.
3. With the function speed switch turned to the fully
CCW position, activate the Telescope out switch and
adjust Threshold to 84 mA.
4. With the function speed switch turned to the fully
CW position, activate the Telescope out switch and
adjust Hi Range to 900 mA.
5. With the function speed switch turned to the fully
CW position, activate the Platform Rotate switch and
adjust Lo Range to 300 mA.
6. Set Ramp about 10 turns CW from the fully CCW
position. Adjust Threshold until Platform Rotate just
starts to move when switch is in the "snail" position.
3.12 THROTTLE CHECKS AND
ADJUSTMENTS - DEUTZ F4L-912
ENGINE
NOTE: Never run fuel tank dry. Diesel engines cannot be
restarted after running out of fuel until fuel system
has been air-vented or “bled” of air. See Deutz
instruction manual for procedure.
1. Disconnect actuator cable from throttle lever. With
the aid of an assistant, start the engine and allow it
to come up to operating temperature. Adjust throttle
lever stop until engine runs at 1800 RPM. Shut down
engine. Reattach actuator cable to throttle lever,
making sure that low (mid) engine setting remains
the same. If necessary, adjust slide pin to contact
low (mid) engine limit switch at 1800 RPM. Shut
down engine.
2. Start the engine from ground controls and allow to
come up to operating temperature. Inside the
ground control terminal box, attach a “hot” wire from
the 12 Volt power (red) wire at the PLATFORM/
GROUND SELECT switch to terminal 1 (brown/black
wire) on the relay circuit card at the top of the
ground control terminal box. This will cause the
engine to run as if HIGH ENGINE and HIGH DRIVE
are activated. Adjust slide pin to contact high engine
limit switch at 2500 RPM. Remove “hot” wire from
terminal 1 and from PLATFORM/GROUND SELECT
switch. Shut down engine.
NOTE: Actuator cable travel must stop slightly before lever
makes contact with throttle lever stop. Failure to do
so will burn out actuator.
Figure 3-14. Function Control Card Adjustment