Front/Rear Drum System - Manitowoc 999 Service And Maintenance Manual

INTRODUCTION

FRONT/REAR DRUM SYSTEM

See Figures 1-17 and 1-18
The left drum handle (1) operates front drum while right drum
handle (2) operates rear drum. Hydraulic connections
between front or rear drum pump and motor form a closed-
loop system. For load drum operation, system low-pressure
side hydraulic fluid releases load drum brake (3) and drum
pawl (4).
The left travel charge pump supplies pilot pressure for front
and rear motor servo (5) operation. Pressure senders (6) in
high and low-pressure side of rear drum (high-pressure side
of front drum) provides system pressure information to the
PC.
999CSM1-116
+
F15
5A
5D
10A
CB7
K1
8
50 AMP
OFF
RAISE
LOWER
3 1
F4
8 8D
5A
F8
8T
8
5A
F4
8 8D
5A
1-26
ENGINE
RUN
STOP
STOP
5DA
F12
REGULATED 10V DC OUTPUT
3A
FRONT DRUM
OFF
LOWER
RAISE
REAR DRUM
3 14 3
2
BLOCK UP LIMITS
DIGITAL DISPLAY
UP SCROLL
DOWN SCROLL
CRANE MODE
CONFIRM
SELECT
SEAT SWITCH
FRONT DRUM
PRESSURE TRANSDUCER
REAR DRUM
PRESSURE TRANSDUCER
FRONT DRUM
D A
SHAFT
SPEED
F B
ENCODER
REAR DRUM
D A
SHAFT
SPEED
F B
ENCODER
Published 05-16-17, Control # 233-03
Continuous changing of closed-loop fluid occurs through
leakage in motor and external sequence/flow valve (7).
Sequence/flow valve opens at 200 psi (14 bar) and removes
6 GPM (23 L/min) of hot fluid from system by dumping fluid in
the motor case where fluid returns to tank through cooler.
When a front or rear load drum rotates, speed encoder (8)
sends an input signal to the PC. The PC sends an output
signal that enables rotation indicator (9) in selected load
drum control handle. Rotation indicator on top of each
control handle pulsates with a varying frequency that
indicates rotational speed of load drum. As drum rotates
faster, the indicator pulsates faster.
START
3
7
8P1
WA-01
WA-03
WA-04
RIN
WD-19
WD-18
WB-26
WB-33
PROGRAMMABLE
CONTROLLER
WB-09
WB-10
WB-34
WA-22
3 6
WA-23
WD-01
WD-02
3 8
WD-03
WD-04
999 SERVICE/MAINTENANCE MANUAL
K1
MS1
0
SYSTEM FAULT
25
BUZZER
OPERATING LIMIT
25A
BEEPER
FRONT DRUM
B A
WC-05
PUMP CONTROL
EDC
REAR DRUM
B
WC-06 PUMP CONTROL
EDC
FRONT DRUM
MOTOR CONTROL
WD-24
FD
PCP
REAR DRUM
MOTOR CONTROL
WD-25
RD
PCP
FRONT DRUM
WD-27 ROTATION INDICATOR
REAR DRUM
WD-28
ROTATION INDICATOR
WD-32 FRONT DRUM PAWL IN
HS
FRONT DRUM
WD-33
PAWL OUT
HS
20
WD-34 REAR DRUM PAWL IN
HS
REAR DRUM
WD-35
PAWL OUT HS
25
WC-18
FRONT DRUM
BRAKE
HS
WD-08
REAR DRUM
WC-19
BRAKE HS
WD-09
_
0
12 3
A
3
13
3
9
19
24
10 3
16
3
11
21
FIGURE 1-17