INTERACTIVE SCHEMATIC

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EC-C3EC-C2 E-C60

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Hydraulic System - Attachment345B Excavator

ALB1-UPAGS1-UP4SS1-UP9GS1-UPDCW1-UP

©2015 Caterpillar, All Rights Reserved Printed in U.S.A.

SENR1980-01July 2015

Combined Function - Two Pump Flow

COMPONENT LOCATION

Description PartNumber

SchematicLocation

MachineLocation

Switch As - Pressure (Pilot Hydraulic Oil) 106-0179 C-2 1Valve Gp - Auxiliary Manifold 122-4850 A-4 2Valve Gp - Control 9Q-9728 B-3 3Valve Gp - Flow Control 4I-7836 B-7 4Valve Gp - Manual 144-2145 E-3 5Valve Gp - Relief 6E-5234 E-3 6Valve Gp - Relief (Line) 177-2708 C-4 7Valve Gp - Shuttle 8J-6875 B-3 8Valve Gp - Shuttle (Flow Control) 8J-6875 B-7 9

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 RESTRICTIONVARIABLE and PRESSURE

COMPENSATED

PRESSURECOMPENSATION

PUMP: VARIABLE andPRESSURE COMPENSATED

ENERGY TRIANGLESHYDRAULIC PNEUMATIC

MEASUREMENT

PRESSURE TEMPERATURE FLOW

ROTATING SHAFTS

UNIDIRECTIONAL BIDIRECTIONAL

PUSH-PULL LEVER PEDALGENERAL MANUAL PUSH BUTTON SPRING

MANUAL CONTROL SYMBOLS

HYDRAULIC MOTORS

FIXEDDISPLACEMENT

VARIABLE DISPLACEMENTNON-COMPENSATED

UNIDIRECTIONAL

BIDIRECTIONAL

HYDRAULIC PUMPS

FLUID STORAGE RESERVOIRS

CROSSING AND JOINING LINES

VALVE ENVELOPES VALVE PORTS

BASIC COMPONENT SYMBOLS

FLUID CONDITIONERPUMP or MOTOR

FIXEDDISPLACEMENT

VARIABLE DISPLACEMENTNON-COMPENSATED

UNIDIRECTIONAL

BIDIRECTIONAL

VALVES

PILOT CONTROL SYMBOLSRELEASED PRESSURE

EXTERNAL RETURN INTERNAL RETURN

REMOTE SUPPLY PRESSURE

SIMPLIFIED COMPLETE INTERNALSUPPLY PRESSURE

ACCUMULATORS

SPRING LOADED GAS CHARGED

SOLENOIDor MANUAL

SOLENOIDand PILOT

SOLENOID and PILOT or MANUAL

COMBINATION CONTROLS

SOLENOID SERVO THERMAL DETENT

HYDRAULIC AND PNEUMATIC CYLINDERS

DOUBLE ACTINGSINGLE ACTING

BASICSYMBOL

SPRINGLOADED

CHECK VALVES

TWOPOSITION

INFINITEPOSITIONING

FLOW IN ONEDIRECTION

FLOW ALLOWED INEITHER DIRECTION

THREEPOSITION

CROSSFLOW

PARALLELFLOW

INTERNAL PASSAGEWAYS

NORMAL POSITION

A B

P T

A B

P TSHIFTED POSITION INFINITE POSITION

CONTROL VALVES

ATTACHMENT

MANUAL SHUTOFF

SHUTTLE PILOTCONTROLLED

ELECTRICAL SYMBOLSHydraulic Symbols (Electrical)

325-AG135 PK-14

Circuit IdentificationNumber

Wire Color Wire Gauge

Harness identification codeThis example indicateswire 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 ColorCircuit Number Identification

B A

Wire

Wire

(EXAMPLE VALVE)

Current Standard

Transducer(Fluid)

Transducer(Gas / Air)

G

Generator

Electrical WirePressure Switch

MElectric Motor

Pressure Switch (Adjustable)

Temperature Switch

PressureSymbol

TemperatureSymbol

LevelSymbol

FlowSymbol

Electrical Symbols (Electrical)

T

Components are shown installed on a fully operable machine with the key and engine off, transmission shifterin neutral and with parking brake set.Refer to the appropriate Service Manual for Troubleshooting, Specifications and Systems Operations.

ATTACHMENT: COMBINED FUNCTION - TWO PUMP FLOW

SCHEMATIC PART NUMBER: 149-7572, CHANGE: 08, VERSION: -

THIS SCHEMATIC IS FOR THE 345B EXCAVATOR HYDRAULIC SYSTEM

MEDIA NUMBER: SENR1980-01

Refer to the Parts Manual using a specific serial number prefix in SIS before ordering parts from this schematic.

A

B

C

D

E

1234567

A

B

C

D

E

1234567

LINE PATTERNS

(52) VALVE GP - CONTROL138-1234

Callout Number(Machine Location from

Component LocationsTable)

ComponentName

Part Number

MAIN CONNNECTOR LINE

PILOT LINE

DRAIN LINE

B A

DR1

MU

SWINGMOTOR

PG1

SWINGMOTOR

MU

DR2

AB

3GP2GP

(COOLANT)

B

STICK SWING

BOOMBUCKET

JR1JR3JR4

JR2

JRTJRP

JL2 JL4JL1JL3AB

JLTJLP

AR1BR1 AL2BL2

X

C D

A E B

DR

HL

dL5

aL5BL4bL4AL3BL3aL3bL2AL1BL1aL1PSWaR1aR2AR2BR2bR3aR4

Y

HR

AR4

R1

dSW LP1Rb2Rb PR Pp1 bL1 PAT aL2 bL3 aL4

BOOM(1)

BUCKETATCHTRAVEL(R)

PiLaR3dR4

SA5 SA4 SA3 SA2 SA1

SB5 SB4 SB3 SB2 SB1 SP

(B)

BPi

(F)(B)(R) (L)

SWING

(F)

LL1S

(DOWN)(OPEN)(FWD)(FWD)(L)(IN)(UP)

(CLOSE) (UP) (IN,OUT,DOWN)

dR5 (BACK)(BACK)(R)

AR3

R1

S

R2X1

X2

M3X3A1M1

A2M2

R1

A3

T1

RIGHT

L'L'

(OUT)

BR3

R2

'A'B

BR

R3

BR

MB MAMB

A'B'

T1

LEFT

APi2

A'

PP2

Pi8

PSA

PG

B'

STICK(1)

STICK(2)

(1) SWITCH ASPRESSURE

PILOT HYDRAULIC OIL106-0179

BOOM(2)

TRAVEL(L)

TOUTDR1DR2DR3

B A

DR4

DR5DR6

(SLOW)

Pi3

(TRAVEL) (SWING)

PINPEU

(PUMP)

Pi1Pi2C/V

TRACK

JPiPi5

(RELIEF)

T2

PTA

X

T2

MA

(OIL)

TT TP

TRAVEL(R)

PAC

TRAVEL(L)

(9) VALVE GPSHUTTLE

(FLOW CONTROL)8J-6875

(4) VALVE GPFLOW CONTROL

4I-7836

TLA1

BDr

2ART2ALT TRA1

B

X

PSL

A

X

APi

ADr

AL4

T

S3S2S1

P

SINGLEACTION

DOUBLEACTION

DOUBLE

SINGLEDOUBLE

SINGLE

FOR SINGLE

(6) VALVE GPRELIEF6E-5234

(7) VALVE GPRELIEF (LINE)

177-2708

(8) VALVE GPSHUTTLE8J-6875(3) VALVE GP

CONTROL9Q-9728

(5) VALVE GPMANUAL144-2145

ACTION

(2) VALVE GPAUXILIARY MANIFOLD

122-4850

MACHINE COMPONENT LOCATIONS

9

8

76

54

3

2

1