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Reference
Only
Manitowoc
Published 05-16-17, Control # 233-03
1-23
999 SERVICE/MAINTENANCE MANUAL
INTRODUCTION
1
also sends a signal to reduce the displacement of the motor.
The PC is continuously balancing the system pressure and
the motor displacement angle so the motor displacement
goes to minimum when handle is all the way back, if the
to r qu e o n t h e m o t or i s no t t o o h i gh . K no w i ng th e
displacement of the motor, the PC may then control the
speed that the motor turns by regulating the flow through the
pump.
When boom hoist handle is moved to neutral position, the
PC sends an output signal to boom hoist pump EDC to
decrease swashplate angle, reducing oil flow output. This
shifts the motor back to maximum displacement for slower
output speed to slow the drum rotation. The PC stores the
load holding pressure in pressure memory. After control
handle neutral switch opens, the PC sends an output signal
to disable brake release solenoid HS-13 to spring-apply
brake before boom hoist pump de-strokes.
Boom Stop Cylinders
If boom is raised to 81°, springs in boom-stop cylinders slow
the boom opposite movement. At approximately 90° boom-
stop springs bottom out and boom physically stops. If boom
is raised to maximum boom up stop angle of 83° above
horizontal or 88° above horizontal with luffing jib, the boom
up limit switch (12) opens the circuit. Boom hoist pump de-
strokes and boom hoist brake spring-applies. Operating limit
(MAX UP 1) is displayed as limit switch is tripped. Lower the
boom to correct problem.
Boom Hoist Lower
See Figures
When
boom hoist handle (1) is moved forward to move boom
down, handle neutral switch closes, sending an input voltage
of 5 volts or less to PC. The PC sends a negative output
voltage to boom hoist system pump EDC (3) and a positive
voltage to motor PCP (11).
FIGURE 1-15
WA-01
8D
8
WB-10
WB-09
SELECT
CONFIRM
CRANE MODE
8T
0
0
8
WB-26
WB-33
DOWN SCROLL
UP SCROLL
WA-24
K1
F4
F8
PRESSURE TRANSDUCER
BOOM HOIST
SYSTEM FAULT
BUZZER
25A
25
OPERATING LIMIT
BEEPER
5A
5A
+
_
ENGINE
10A
5D
5A
F15
STOP
STOP
3
RUN
START
7
MS1
K1
5DA
8
8P1
50 AMP
CB7
SEAT SWITCH
WB-34
999CSM1-114
F12
3A
REGULATED 10V DC OUTPUT
RAISE
OFF
LOWER
BOOM HOIST HANDLE
WA-05
WD-18
WD-19
DIGITAL DISPLAY
HS
13
BOOM HOIST
3
8
3
1
3
6
WC-14
BOOM HOIST
B
A
EDC
WD-37
HS
15
BOOM HOIST PAWL OUT
WD-10
WC-09
3
3
3
11
3
2
3
12
3
7
BLOCK UP LIMITS
MAXIMUM BOOM
ANGLE LIMIT
RIN
WB-12
WE-29
BH
PCP
BOOM HOIST
MOTOR CONTROL
PUMP CONTROL
WD-29
ROTATION INDICATOR
BOOM HOIST
14
HS
BOOM HOIST PAWL IN
WD-36
DRUM BRAKE
BOOM HOIST
SPEED
ENCODER
F
A
B
D
DRUM SHAFT
PROGRAMMABLE
CONTROLLER
WD-05
WD-06
Summary of Contents for 999
Page 1: ...R e f e r e n c e O n l y Service Maintenance Manual Manitowoc 999 ...
Page 2: ...R e f e r e n c e O n l y ...
Page 4: ...R e f e r e n c e O n l y THE ORIGINAL LANGUAGE OF THIS PUBLICATION IS ENGLISH ...
Page 297: ...R e f e r e n c e O n l y ...
Page 298: ...R e f e r e n c e O n l y ...