Snorkel TB42J, Operato'S Manual

Page: 26 / 68

Chapter 6 – Controls
22 TB42J – 0172310
Push the emergency stop button in when the upper con-
trols are not in use to protect against unintentional op-
eration.
Speed Knob
Use the boom speed control knob (refer to Figure 6.6) to
control the speed of the following boom functions.
• Tip boom extend/retract
• Jib up/down
• Platform rotate clockwise/counterclockwise
Set the knob to slow when beginning a boom movement.
The speed may be increased by slowly rotating the knob
toward fast. For smooth operation, rotate the knob to
slow when ending boom movement.
Boom Joystick
The boom joystick (refer to Figure 6.6) is used to raise
and lower the main boom and to rotate the turntable. The
boom and turntable functions may be operated simulta-
neously.
Note
The distance the joystick is moved is proportional to the
speed of the function.
Hold the joystick forward to raise the main boom and
backward to lower the boom.
Hold the joystick to the right to rotate the turntable coun-
terclockwise and to the left to rotate the turntable clock-
wise.
Drive Joystick
The drive joystick (refer to Figure 6.6) is used to control
forward and reverse motion of the aerial platform. It is
also used to steer the machine. The steering and drive
functions may be operated simultaneously.
Note
The distance the joystick is moved is proportional to the
speed of the function.
Hold the joystick forward to move the aerial platform for-
ward and backward to move in reverse as indicated by
the directional arrows on the chassis.
Hold the joystick to the right to steer the aerial platform
to the right and to the left to steer to the left as indicated
by the directional arrows on the chassis.
Note
The steering wheels are not self-centering. Set the steer-
ing wheels straight ahead after completing a turn.
Drive Range Switch
The drive range switch (refer to Figure 6.6) has two posi-
tions to select drive wheel operation:
• HI – high speed and low torque operation.
• LO – low speed and high torque operation.
Jib Articulation Switch
The jib switch (refer to Figure 6.6) is used to raise or
lower the jib. The switch is spring returned to the center
off position.
Hold the switch up to raise the jib. Hold the switch down
to lower the jib.
Note
The jib and platform rotate functions can not be oper-
ated at the same time. The platform rotate function will
override the jib function.
Platform Level Switch
The level switch (refer to Figure 6.6) is used to level the
platform floor with respect to the ground. The switch is
spring returned to the center off position.
Hold the switch up to tilt the platform floor upward or
away from the ground. Hold the switch down to tilt the
platform floor downward or toward the ground.
Boom Extend/Retract Switch
The boom extend/retract switch (refer to Figure 6.6) is
used to extend or retract the tip boom. The switch is
spring returned to the center off position.
Hold the switch down to extend the tip boom. Hold the
switch up to retract the tip boom.
Engine/Emergency Power Switch
The engine/emergency power switch (refer to Figure 6.6)
is spring returned to the engine position for aerial plat-
form engine operation.
Place the switch in the emergency power position to op-
erate aerial platform functions using the emergency power
system. Place the switch in the off position to disengage
the emergency power system.
Note
The emergency power system is for lowering the platform
during an emergency and is not intended for normal ma-
chine operation.
If the engine is running, it will stop when the switch is
placed in the emergency power position.
Throttle Switch
The throttle switch (refer to Figure 6.6) is used to set the
engine throttle speed to either low or high idle.
Place the switch in the low position for normal machine
operation and in high to drive at maximum speed.
Cummins engines have a three speed throttle operation
from the upper controls. Independent of the throttle switch,
the platform foot switch, when depressed, increases the
engine speed from low to mid-range.