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Hydraulic Symbols (Electrical)

Electrical Symbols Table

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)

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

FLUID POWER SYMBOLS

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

SOLENOID or MANUAL

SOLENOID and 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

T

VA Boom

RENR3278August 1998

320B, 322B and 325B ExcavatorHydraulic System320B:1XS1-UP7JR1-UP2AS1-UP9WS1-UP5MS1-UP6LW1-UP3YZ1-UP

322B:2ES1-UP1ZS1-UP

325B:6DN1-UP8FN1-UP4DS1-UP5BS1-UP

1998 CaterpillarAll Rights Reserved

Printed in U.S.A.

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THIS SCHEMATIC IS FOR THE 320B, 322B AND 325B EXCAVATORSPART NUMBER: 149-2310Components are shown installed on a fully operable machine.

Refer to the appropriate Service Manual for Troubleshooting, Specifications and Systems Operations.

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