INTERACTIVE SCHEMATIC
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EC-C3
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E-C61
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©
2006 Caterpillar, All Rights Reserved
Printed in U.S.A.
Alternate Control Pattern - 2 Way
KENR6569
August 2006
TBA1-UP
FPC1-UP
ESD1-UP
WDE1-UP
TDG1-UP
TAJ1-UP
DHP1-UP
GJR1-UP
PJW1-UP
BWY1-UP
345C Excavator
Hydraulic System - Attachment
COMPONENT LOCATION
Description
Part
Number
Machine
Location
Schematic
Location
Valve Gp - 2 Way Pattern Changer 118-5984 1 B-8
Accumulator Gp - Pilot Manifold Note B 19 B-5
Cylinder Gp - Boom Note A 21 E-2
Cylinder Gp - Bucket Note A 22 E-3
Cylinder Gp - Stick Note B 23 E-8
Filter Gp - Drain Return Note B 24 A-6
Filter Gp - Pilot Note B 25 A-4
Filter Gp - Return Oil Note B 26 A-6
Motor Gp - Cooling Fan
Note B 27 A-7
Motor Gp - Left Travel
Note B 28 F-5
Motor Gp - Right Swing
Note B 29 F-6
Motor Gp - Right Travel
Note B 30 F-4
Motor Gp - Swing Left
Note B 31 F-7
Pump Gp - Cooling Fan Note B 32 B-2
Pump Gp - Drive / Idler / Pilot Hydraulic Note B 33 B-3
Swivel Gp
Note B 34 E-5
Tank Gp - Hydraulic Oil
Note B 35 A-6
Valve Gp - Boom/Swing Priority Note B 36 B-4
Valve Gp - Cooler Bypass Check Note B 37 B-7
Valve Gp - Left Swing Motor Note B 38 E-7
Valve Gp - Left Travel / Brake Note B 39 E-5
Valve Gp - LH Pilot Control (Stick/Swing) Note B 40 C-8
Valve Gp - Main Control Note B 41
Valve Gp - Pilot Manifold Note B 42
Valve Gp - Pilot Travel Note B 43
Valve Gp - RH Pilot Control (Bucket/ Boom) Note B 44 C-7
Valve Gp - Right Travel / Brake Note B 45 E-4
Valve Gp - Slow Return Check Note B 46 B-7
Note A: Refer to parts manual for specific cylinder information.
Note B: Part Numbers are located on the main Hydraulic System Schematic according to the
effectivity of the machine.
Attachment
Standard 345C
D-4
B-5
D-8
TAP LOCATION
Tap
Number
Description
Schematic
Location
AA Pilot Pump Delivery Pressure A-4
BB Drive Pump Delivery Pressure B-2
CC Pump Power Shift Pressure A-2
DD Idler Pump Delivery Pressure A-2
SOS Hydraulic Oil Sampling Port A-4
FLUID POWER SYMBOLS
ONE POSITION
TWO POSITION
THREE POSITION
VENTED
PRESSURIZED
RETURN ABOVE FLUID LEVEL
RETURN BELOW FLUID LEVEL
LINES CROSSING LINES JOINING
TWO-WAY
THREE-WAY
FOUR-WAY
SPRING
CONTROL VALVES
RESTRICTION
LINE RESTRICTION
(FIXED)
2-SECTION PUMP
MAIN
AUX.
SPRING
(ADJUSTABLE)
VARIABILITY
LINE RESTRICTION
(VARIABLE)
LINE RESTRICTION
VARIABLE and PRESSURE
COMPENSATED
PRESSURE
COMPENSATION
PUMP: VARIABLE and
PRESSURE COMPENSATED
ENERGY TRIANGLES
HYDRAULIC PNEUMATIC
MEASUREMENT
PRESSURE
TEMPERATURE
FLOW
ROTATING SHAFTS
UNIDIRECTIONAL BIDIRECTIONAL
PUSH-PULL LEVER PEDALGENERAL MANUAL PUSH BUTTON SPRING
MANUAL CONTROL SYMBOLS
HYDRAULIC MOTORS
FIXED
DISPLACEMENT
VARIABLE DISPLACEMENT
NON-COMPENSATED
UNIDIRECTIONAL
BIDIRECTIONAL
HYDRAULIC PUMPS
FLUID STORAGE RESERVOIRS
CROSSING AND JOINING LINES
VALVE ENVELOPES
VALVE PORTS
BASIC COMPONENT SYMBOLS
FLUID CONDITIONER
PUMP or MOTOR
FIXED
DISPLACEMENT
VARIABLE DISPLACEMENT
NON-COMPENSATED
UNIDIRECTIONAL
BIDIRECTIONAL
VALVES
PILOT CONTROL SYMBOLS
RELEASED PRESSURE
EXTERNAL RETURN
INTERNAL RETURN
REMOTE SUPPLY PRESSURE
SIMPLIFIED
COMPLETE
INTERNAL
SUPPLY PRESSURE
ACCUMULATORS
SPRING LOADED GAS CHARGED
SOLENOID
or MANUAL
SOLENOID
and PILOT
SOLENOID and
PILOT or MANUAL
COMBINATION CONTROLS
SOLENOID
SERVO
THERMAL
DETENT
HYDRAULIC AND PNEUMATIC CYLINDERS
DOUBLE ACTINGSINGLE ACTING
BASIC
SYMBOL
SPRING
LOADED
CHECK VALVES
TWO
POSITION
INFINITE
POSITIONING
FLOW IN ONE
DIRECTION
FLOW ALLOWED IN
EITHER DIRECTION
THREE
POSITION
CROSS
FLOW
PARALLEL
FLOW
INTERNAL PASSAGEWAYS
NORMAL POSITION
A B
P T
A B
P T
SHIFTED POSITION
INFINITE POSITION
CONTROL VALVES
ATTACHMENT
MANUAL SHUTOFF
SHUTTLE PILOT
CONTROLLED
ELECTRICAL SYMBOLS
Hydraulic Symbols (Electrical)
325-AG135 PK-14
Circuit Identification
Number
Wire Color
Wire Gauge
Harness identification code
This example indicates
wire 135 in harness "AG".
325-PK-14
Wire Gauge
Wire Color
Circuit Number
Identification
Wire Number Identification Codes
Current Standard
Previous Standard
Electrical Schematic Example
Hydraulic Schematic Example
325-PK
Wire Color
Circuit Number
Identification
B
A
Wire
Wire
(EXAMPLE VALVE)
Current Standard
Transducer
(Fluid)
Transducer
(Gas / Air)
G
Generator
Electrical Wire
Pressure Switch
M
Electric Motor
Pressure Switch
(Adjustable)
Temperature Switch
Pressure
Symbol
Temperature
Symbol
Level
Symbol
Flow
Symbol
Electrical Symbols (Electrical)
T
THIS SCHEMATIC IS FOR THE 345C (ATTACHMENT)
PART #: 239-8859 (HE) CHG01
Components are shown installed on a fully operable machine with the key and engine off and
transmission shifter in neutral.
Refer to the appropriate Service Manual for Troubleshooting, Specifications and Systems Operations
LINE PATTERNS
Drain / Return Lines
Component Group
Pilot / Load Sensing Pressure
Pressure Line
Attachment
Air Line
CALLOUTS
Taps (Pressure, Sampling,Sensor) by letter
YY
DRAIN / RETURN LINE
HYDRAULIC CIRCUIT COLOR DESCRIPTIONS
PILOT PUMP OUTPUT
SUPPLY LINE
DRIVE PUMP OUTPUT
IDLER PUMP
POWER SHIFT CONTROL CIRCUIT
COOLING FAN PUMP
ATTACHMENT CONTROL CIRCUIT
BUCKET CONTROL & BUCKET CYLINDER CIRCUIT
RIGHT TRAVEL CONTROL & RIGHT TRAVEL MOTOR CIRCUIT
TRAVEL SPEED CONTROL CIRCUIT
STICK CONTROL & STICK CYLINDER CIRCUIT
BOOM CONTROL & BOOM CYLINDER CIRCUIT
LEFT TRAVEL CONTROL & LEFT TRAVEL MOTOR CIRCUIT
SWING CONTROL & SWING MOTOR CIRCUIT
SWING BRAKES
BR1
(22) CYLINDER GP
BUCKET
(21) CYLINDER GP
BOOM
(23) CYLINDER GP
STICK
PG2
PB2
DE2
B2
A2
PA2
M2
DB2
PG1
PA1
M1
DB1
B
A
X
BA
B
A
AG
AGBG
BG
T2
T2
T1
T1
BR
X
B
A
L
BR3 AR3
AR2 BR2
AL3BL3 BL4 AL4
118-5984
PATTERN-2
BHL
PATTERN-1
SAE(JIS)
1
2
3
4
A
B
C
D
TRAVEL(R)TRAVEL(L)
SWINGSTICK
OUT IN R L
TP
TT
BACK FWD FWD
T2T1 T3 T4
BACK
JLP
JLT
JL1 JL3 JL2 JL4
BOOMBUCKET
OPEN CLOSE UP
JR4 JR2 JR3 JR1
JRP
JRT
bR1 aR1 aL1 bL1
aR2
bR2
bR3 aR3
bL3
bL4 aL4
L2
L3
A
B
µµ
µ
DOWN
Pi1P2 P-IN PSA2 DR1
T-OUT2 DR2
DR3
DR4
Pi2 DR5
DR6T-OUT1
P1 P2
T
B1
A1
B2 A2
P1
PSA1
T
OUT
8
6
5
NO.1
(TRAVEL)
NO.2
(SWING)
NO.3
(LOCK)
A4
B1 Dr1 Di PS2 PB
Pi2
B
D0
a2
a5
a3
A2
a1
a4
A1
PSV
IN
1
7
LL1
X
PR
PL
BOOM(1) STICK(2)BUCKETATCH
HL
aL5
Dr
R2
X
dL5(DOWN)
BPiBDr
(UP)(CLOSE)
AL2BL2
aL2PAT
(OPEN)bL2
(B) (F)
PTAPSW
(BACK)
aL4
(IN)
CV1
CV2
A
MU
(OUT)
bL1
BL1
AL1
bL3
BL3 AL3 BL4
AL4
TRAVEL(R)
TRAVEL(L)SWING
Pp1
Pi1
(FWD)
dST1
(BACK)(F)(B)(R)
(FWD)
(L)
(R) (L)
dSWPiL
(OUT)
Pp2
PiH
MU1
aR3
BR2
AR2
bR2
BR1
AR1
bR1
aR2
aR1
PR
PL aL1 aL3
bL4
STICK(1)BOOM(2)
R1
Y
HR
AR4
R3
dR4 (IN)
APiADr
APi2
dR5
A A
MU2
MU1
CV CV
AR3BR3aR4
bR3
AR1
AL1 BL1
PS1
PB1
(32) PUMP GP
COOLING FAN
(36) VALVE GP
BOOM/SWING
PRIORITY
(33) PUMP GP
DRIVE/IDLER
PILOT HYDRAULIC
(25) FILTER GP
PILOT
PCPG
(42) VALVE GP
PILOT
MANIFOLD
(35) TANK GP
HYDRAULIC OIL
(26) FILTER GP
RETURN OIL
(19) ACCUMULATOR GP
PILOT MANIFOLD
(24) FILTER GP
DRAIN RETURN
(27) MOTOR GP
COOLING FAN
(37) VALVE GP
COOLER
BYPASS CHECK
(46) VALVE GP
SLOW RETURN CHECK
(40) VALVE GP
LH PILOT CONTROL
STICK/SWING
(44) VALVE GP
RH PILOT
CONTROL
BUCKET/BOOM
(43) VALVE GP
PILOT
TRAVEL
(38) VALVE GP
LEFT SWING MOTOR
(28) MOTOR GP
LEFT TRAVEL
(39) VALVE GP
LEFT
TRAVEL/BRAKE
(31) MOTOR GP
LEFT SWING
(29) MOTOR GP
RIGHT SWING
(30) (MOTOR GP
RIGHT TRAVEL
(45) VALVE GP
RIGHT
TRAVEL/BRAKE
(34) SWIVEL GP
(41) VALVE GP
MAIN CONTROL
(UP)
(1) VALVE GP-PILOT
PATTERN CHANGER
2-WAY
aL3
(24) FILTER GP
DRAIN RETURN
DR
DR1
BB
CC
DD
SOS
AA
µµµ µµµµ µ
µ
MU2
BR
L
B
A
DE1
B1
A1
S
2
1
3
4
56
7
8
A
C
D
E
F
1
23
4
56
7
8
A
B
C
D
E
F
B
MACHINE COMPONENT LOCATIONS
46
46
45
45
44
44
43
43
42
42
41
41
40
40
39
39
38
38
37
37
36
36
35
35
34
34
32
32
31
31
30
30
29
29
28
28
27
27
26
26
25
25
24
24
23
23
22
22
21
21
21
19
19
1
1
VIEW ALL CALLOUTS
PUMP AND FILTER GROUP
33
SOS
DD
CC
BB
AA
VIEW ALL CALLOUTS
