Manitowoc 18000, Service Maintenance Manual, Page: 203 / 316

Reference
Only
Manitowoc
Published 12-05-17, Control # 035-23
4-7
18000 SERVICE/MAINTENANCE MANUAL BOOM
4
BOOM AND LUFFING JIB ANGLE
INDICATOR CALIBRATION
The subject cranes do not have an angle indicator junction
box mounted on the boom butt or on the luffing jib butt like
other cranes manufactured by Manitowoc.
The angle indicator potentiometers are located inside the
node controllers mounted on the boom top and on the luffing
jib top.
The boom and luffing jib angles are calibrated automatically
by the crane’s programmable controller as part of the load
indicator calibration procedure (see separate Rated Capacity
Indicator/Limiter Manual for instructions).
MAST ANGLE INDICATOR ADJUSTMENT
Mast Angle Indicator
The mast angle sending unit ( Figure 4-6 ) houses a
pendulum-type 120° potentiometer ( Figure 4-7 ) which
p r o v i d e s a d i g i ta l e l e c t r o n i c i n p u t t o t h e c r a n e ’s
programmable controller. The programmable controller uses
the signal for the following purposes:
• Automatically control the position of the mast raising
cylinder and levers during crane setup
• Allow the operator to monitor the mast angle on the
digital display during crane setup
Adjusting Angle
Perform the following adjustment steps at initial installation,
after installing a new sending unit or potentiometer, and
during assembly. Mast angle should be 0° when mast is fully
lowered to the rear (transport position).
NOTE: Mast must be in transport position when checking
or adjusting angle indicator.
1. Park crane on a solid, level surface
2. Lower mast to transport position
3. Place an electronic level on mast ( Figure 4-6 )
4. Record angle indicated on level
5. Scroll to angle on digital display in operator’s cab
6. Angle shown on digital display must match angle
recorded in step 4 plus or minus one degree
7. If necessary, loosen mounting screws and rotate
sending unit box in mounting slots until reading on digital
display matches angle on level.
8. Securely tighten mounting screws to lock adjustment
Sending Unit Assembly
Replacement sending units can be either the pendulum-type
120° potentiometer (past production) or solid state sensor
(current production).
Pendulum-type 120° Potentiometer
When replacing parts in the pendulum-type potentiometer
sending unit, take the following precautions (see
Figure 4-7 ,
View A):
1. Mount potentiometer at angle shown.
2. Connect black, green, and white wires from receptacle
to proper terminals on terminal strip.
Typical Node Controller Installation
on Boom or Luffing Jib Top
Potentiometer
Mounted Inside
P1518
FIGURE 4-5
FIGURE 4-6
P317
Electronic
Level
Angle
Sending Unit
Box
Left
Mast Leg