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Reference
Only
INTRODUCTION
999 SERVICE/MAINTENANCE MANUAL
1-40
Published 05-16-17, Control # 233-03
The load weight attempts to drive motor faster than return
fluid can return to low-pressure side of pump. Auxiliary drum
charge pump maintains the fluid supply at a positive
pressure to auxiliary drum motor. The position of the pump
swashplate restricts returning fluid and pressure builds on
the return side of closed-loop system, acting as a brake
against auxiliary drum motor to control the lowering speed.
When auxiliary drum handle is moved to neutral position, the
PC sends an output signal to pump EDC to decrease
swashplate angle, reducing flow output. The PC also shifts
the motor back to maximum displacement for slower output
speed to slow the drum rotation. The PC shifts the pump
swashplate through neutral until the EDC has a slightly
positive signal. This shifts the swashplate in the positive
direction and builds pressure on high-pressure side of
closed-loop. The PC stores load-holding pressure in
pressure memory. After control handle neutral switch opens,
the PC sends an output signal to disable brake release
solenoid HS-26 to spring-apply brake before auxiliary drum
pump de-strokes.
FIGURE 1-28
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-27
K1
F4
F8
PRESSURE TRANSDUCER
AUXILIARY DRUM
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
999CSM1-128
F12
3A
REGULATED 10V DC OUTPUT
RAISE
OFF
LOWER
AUXILIARY HANDLE
WA-09
WD-18
WD-19
DIGITAL DISPLAY
HS
26
AUXILIARY DRUM
3
9
3
1
WE-37
AUXILIARY DRUM
B
A
WC-08
HS
28
AUX. DRUM PAWL OUT
WD-12
WC-25
3
2
3
6
3
14
3
12
3
8
BLOCK UP LIMITS
RIN
WE-30
AUX
PCP
AUX. DRUM
MOTOR CONTROL
PUMP CONTROL
WD-30
ROTATION INDICATOR
AUXILIARY DRUM
27
HS
AUX. DRUM PAWL IN
WC-07
DRUM BRAKE
AUX. DRUM
SPEED
ENCODER
F
A
B
D
FLANGE
PROGRAMMABLE
CONTROLLER
WE-01
WE-02
3
10
AUX
EDC
UP
DOWN
C
D
WE-36
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 ...