SANY Crawler Hydraulic Excavator (SY195C9, SY205C9, SY215C9, SY225C9). Shop Manual (2013)

Structure and Function

Wire No.

Diameter/Color code

Wire color

Wire No.

Diameter/Color code

Wire color

Black

0.5VW

Violet+white

Br(R)

Brown

0.5YB

Yellow+black

0.85W

White

0.5WO

White+orange

Red+blue

0.5PB

Pink+black

Green

0.5VR

Violet+red

0.5BL

Black+blue

0.5BG

Black+green

0.5R

Red+blue

0.5WY

White+yellow

0.5Y

Yellow

0.5WR

White+red

0.5BR

Black+red

0.5BrW

Brown+white

0.5BrY

Brown+yellow

0.5GO

Green+orange

0.5BY

Black+yellow

0.5Sb

Sky blue

0.5GW

Green+white

0.5OW

Orange+white

0.5LO

Blue+orange

1.25V

Violet

0.5PG

Pink+green

1.25RG

Red+green

0.5RY

Red+yellow

1.25RW

Red+orange

0.5BW

Black+white

0.85GL

Green+Blue

0.5LgR

Light green+red

Code

Name

Code

Name

Code

Name

Condenser high speed

AC_M

A/C amplifier

FU_CD

Condenser fuse

RL_CH

relay

BAT

Battery

FU_M

A/C main fuse

RL_SF

Protective relay

BLC

Speed regulating resistor

Alternator

S_SD

Sunlight sensor

Condenser pressure

CM_B

Battery relay

M_AM

A/M servo motor

SP_CD

switch

Diode

M_B

Blower motor

SP_HL

HI/LO pressure switch

D₁

Diode 1

M_CD

Condenser motor

Switcher

Internal/External air servo

D₂

Diode 2

M_RF

TH_AM

External air thermistor

motor

EC_C

Compressor clutch

M_V1

Air outlet servo motor

TH_F

Anti-frosting thermistor

FL₁

Fuse

M_V2

FRONT outlet servo motor

TH_I

Internal air thermistor

FL₂

Fuse

R_CD

Condenser resistor

TH_W

Water temp. thermistor

FU_BM

Blower fuse

RL_BM

Blower main relay

RL_CC

Compressor relay

RL_CD

Condenser relay

4-133

Structure and Function

4.7.4 Refrigeration principle

4.7.4.1 Refrigeration cycle diagram

Cool air

Expansion valve

Lo temp\Lo press liquid (Mist)

Evaporator

Cooling fan

Blower

Air in cab

Out side fresh air

Hi-temp hi-pres gas

Lo-pres.

Hi-pres.

side

Compressor

Hot air

Lo-pressure portion

Hi-pressure portion

ZX215-1002141

4.7.4.2 Heating cycle diagram

Radiator

Water valve control

Water pump

Hot air

Engine

Blower motor

Internal air

Low tempr water

High temp water

ZX215-1002142

4-134

Structure and Function

4.7.5 Compressor

ZX215-1002143

1) Stator

9) Slipper

2) Front radial bearing

10) Front cylinder block

3) Thrust bearing

11) Piston

4) Front radial bearing

12) Front cylinder head

5) Rear cylinder head

13) Shaft seal

6) Safety valve

14) Main shaft

7) Rear cylinder block

15) Hub

8) Swash plate

16) Rotor

4-135

Structure and Function

Operating principle

Compressor type: 10S15C. This compres-

back and forth and transforms the refrigerant

sor has 5 plungers in total with a piston on

sucked from the evaporator from low tempera-

both sides of each plunger. The rotation of

ture and low pressure gas state to high tem-

the swash plate drives the pistons to move

perature and high pressure state.

Process 1

Process 2

HI press.end pipe LO press.end pipe

Valve plate

Outlet valve disc

Main shaft and swash plate

Intlet valve disc

Process 6

Process 3

HI press.end pipe

LO press.end pipe

HI press.end pipe LO press.end pipe

Process 5

Process 4

HI press.end pipe

LO press.end pipe

HI press.end pipe LO press.end pipe

ZX215-1002144

4-136

Structure and Function

4.7.6 Clutch

1) Rotor

2) Stator coil

3) Snap ring

4) Ball bearing

5) Stator

6) Center piece

The electromagnetic clutch is used to

transmit moment of torsion. When the en-

ZX215-1002145

gine is operating, the compressor may not

be working. The clutch controls the opera-

tion of the compressor only when the air

conditioner is under refrigerating mode.

Operating principle

When the A/C switch is turned on, the

clutch coil with an electromagnet gener-

ates a magnetic field and attracts the metal

piece. The stator and rotor of the clutch are

engaged and drives the main shaft of the

compressor into rotation.

4-137

Structure and Function

4.7.8 Condenser

ZX215-1002146

1) Condenser core

Refrigerant inlet

2) Bracket

Refrigerant outlet

3) Bolt with gasket

Function

Ɣ The condenser converts high-temperature,

high-pressure gas refrigerant (16Kg/cm²,

about 80°C) to high-temperature and high-

pressure liquid refrigerant (16Kg/cm², be-

low 60°C) through radiating.

4.7.7 Expansion valve

Evaporator

1) Spring

2) Diaphragm

3) Probe

4) Needle valve

Operating principle

Ɣ Refrigerant from the receiver tank spurts

Compressor

out via the orifice, turns into low-temper-

Reservoir

ature, low-pressure liquid (mist) after ex-

ZX215-1002147

panding, and enters the evaporator.

4-138

Structure and Function

4.7.9 Evaporator

1) Expansion valve

2) Evaporator

Operating principle

Ɣ The evaporator is a kind of heat exchanger

that looks like a condenser. Hot air in the

cab is conducted into the evaporator via

the blower motor and undergoes heat ex-

change with the surface of the evaporator.

Heat is absorbed and hot air turns into

cold air, which flows into the cab through

the air ducts. Evaporator surface absorbs

ZX215-1002148

heatĺRefrigerant in the evaporator ab-

sorbs heat ĺ Refrigerant evaporates .

Evaporated refrigerant (gas) is absorbed

by the compressor.

4.7.10 Receiver tank

1) Inlet

2) Outlet

3) Receiver/dehydrator

4) Desiccant

Function

Ɣ Temporary storage of refrigerant

Ɣ Dehydration of refrigerant

Ɣ Dust removal from refrigerant

Ɣ Measure the volume of refrigerant

ZX215-1002149

4-139

Structure and Function

4.7.11 Pressure switch

1) O-ring

Pressure

2) Mobile contact point

3) Hood

4) Plug and fixed contact

5) Spring

6) Chamber

7) Diaphragm

Function

Ɣ The pressure switch is installed between

the receiver tank and the expansion

valve (hi-pressure pipe). It is a combina-

tion switch (Hi-Lo pressure combination

switch).

ZX215-1002150

Ɣ When pressure is excessively high, the

compressor stops.

Ɣ When pressure and temperature is very

low, the compressor stops.

Operating features

Feature

DIFF

HI pressure

operating value

Above 0.02 MPa

0.59±0.2 MPa

OFF

LO pressure

2.94~3.19 MPa

0.196±0.02 MPa

0.196~0.250 MPa

operating value

MID pressure

OFF

operating value

1.23±0.1 MPa

1.52±0.08 MPa

4-140

Structure and Function

4.7.12 Fresh air sensor

The fresh air sensor is installed beside the

condenser or around the fresh air inlet. It mea-

sures the temperature of outside air and it is

composed of thermistors.

Technical specifications

Item

Specification

Service voltage range

4.4~5.6 V

Service temp range

-30~60 °C

Storage temp range

-40~90 °C

Resistance value

1700±85ȍ

-10

B constant

3900±195 K

ZX215-1002151

Allowable operating current

1.6 mA (MAX)

4.7.13 Refrigerant

WARNING

Obey local material disposal regula-

tions. Never discharge refrigerant di-

rectly into the air.

Refrigerant R134 a is a harmless gas

under room temperature. It will change

into highly toxic gas when burning.

Refrigerant getting into eyes may cause

blindness. It may cause frostbite if

splashed on your skin.

General property

High heat absorption and easy liquefaction

Non-flammable, nonexplosive

Stable chemical composition

Non-toxic

Non-corrosive

No hazard to clothing

4-141

Structure and Function

2. Refrigerant cycle

Ɣ After evaporation in the evaporator, refrigerant turns from gas into liquid via the compressor

and the condenser, which finishes a refrigerant cycle.

Compressor LO press. side (inlet): LO temp?LO press.?Gas

Pressure/Temperature: 2Kg/cm²đapprox. 8ć

Compressor

Evaporator

IntakeėDischarge

Absorb heatėEmit cold air

Compress HI press. side(outlet): HI temp\HI press.\Gas

Pressure/Temperature:16Kg/cm²ˈapprox. 80ć

Condensor (outlet): LO temp\LO press.\Mist

Pressure/Temperature: 2Kg/cm²ˈapprox. 0~2ć

Condensor (outlet)˖HI temp?HI pressure?Liquid

Expansion valve

Condensor

Pressure/Tempterature˖16Kg/cm²ˈBelow 60ć

Hi pressureėLo pressure

Via radiating: Gas refri-

Hi tempėLo temp

gerantėLiquid refrigerant

LiquidėMist

Ɣ Refrigerant cycle principle (pressure - enthalpy diagram)

lgp

Liquefaction completed

Refrigerant cyclic curve

Liquefaction starts

Throttling point

Condensor

Condensing process

Liquid

Compressing

Expansion valve

process

Compressor

Evaporating process

Evaporator

Gas-liquid mixture

Gasification completed

h=u+Apv(kJ/kg)

U Internal energy p Pressure V Special volume A Joule equivalent

4-142

Structure and Function

3. Feeding of refrigerant

Ɣ Filling method and volume:

1) Refrigerant: HFC-134a

2) Feeding volume: 850±50 g (for reference)

3) Feeding method: Feeding of liquid refrig-

erant from the low-pressure end is not al-

lowed. If feeding operation fails, discharge

the refrigerant that has been fed before re-

feeding.

ZX215-1002153

Ɣ Inspect the state of the refrigerant in the

A/C circulation system through the sight

Sight glass

glass:

1) Correct feeding: Foam is hardly observed

when the refrigerant is flowing. When en-

gine speed increases from idling to 1500

rpm, foam disappears and the refrigerant

Proper filling

turns clear.

2) Over-feeding: No foam can be observed

when refrigerant is flowing.

3) Under-feeding: Foam is always observed

Inadequate filling

when refrigerant is flowing.

ZX215-1002154

4-143

Structure and Function

4. Evacuation

Ɣ No moisture shall exit in the air condition-

ing unit. Refrigerant (R134a) is soluble in

water. Very small amount of moisture in

the unit can cause the orifice of the expan-

sion valve to ice up, or cause the compres-

sor valve to rust. To avoid such problems,

moisture in the system shall be removed

before refrigerant is added. To minimize

the residual moisture in the system, mois-

ture in the system can evaporate through

evacuating.

Evacuating steps

Step 1: Connect the manifold pressure gauge

1) Close the high-pressure valve (HI) and

Valve

low-pressure valve (LO) of the manifold

Lo-pres.gauge

above 750mmHg

Lo-pres.

OFF

pressure gauge.

gauge

Hi-pres. gauge

2) Connect the hoses (red, blue) to the auxil-

iary valve of the compressor.

Hi-pres. valve(ON)

Lo-pres. valve (ON)

Red hose - High pressure side (Mark D)

Green

Red

Blue hose - Low pressure side (Mark S)

Blue

NOTE: Connect the end of the hose with a

L to the auxiliary valve of the compressor.

Compressor

If connected inversely, the valve will not

Vacuum pump (running)

open. Besides, do not inversely connect

ZX215-1002155

the high-pressure end and the low-

pressure end.

3) Connect the green hose to the vacuum

pump.

4-144

Structure and Function

Step 2: Evacuation

1) Open the high-pressure valve (HI) and low-

pressure valve (LO) on the manifold pres-

sure gauge.

2) Turn on the vacuum pump and evacuate

for about 15 minutes.

3) When negative pressure reading on the

gauge (degree of vacuum) reaches above

750 mmHg, turn off the vacuum pump and

close the Hi-pressure valve and the Lo-

pressure valve on the gauge.

Step 3: Air - proof check

1) Keep the Hi- and Lo-pressure valve of the

manifold pressure gauge under closed

state for more than 5 minutes, and make

Valve

Wait 5 min. or more

Lo-press. gauge

sure the pointer on the gauge does not re-

OFF

returns to 0

turn to zero.

Lo-press. gauge

2) If the pointer returns to near zero, a leak-

age is available somewhere. Check and

adjust the pipe joint. Tighten the joint and

Pointer returns

conduct another evacuating operation until

to 0

Tighten pipe joint

no leakage is detected.

ZX215-1002156

4-145

Structure and Function

Step 4: Leak check

1) Connect the green hose that is previously

Valve

connected to the vacuum pump to the

OFF

fluorine cylinder.

2) Connect the other end of the green hose

to the pressure gauge. Open the valve of

Vent valve

the cylinder and press the vent valve of the

Release air

pressure gauge. (Do not press the valve

Open

with naked hand to avoid frostbite caused

by refrigerant). Release the air in the

hose with the pressure of the refrigerant.

Blue

(Release the vent valve when you hear a

Green

R134a

Red

squeezing sound).

To compressor

Fluorine cylinder

ZX215-1002157

3) Add refrigerant until pressure reading on

the Lo-pressure gauge is 1kgf/cm² . Hi-

Valve

pressure valve of the gauge is open at this

Lo-press gauge

at 1kgf/cm²

time. Close the Hi-pressure valve when

OFF

Lo-pres. gauge

feeding is finished.

reads1kgf/cm²

4) Use a leak detector to check if leakage is

Lo-pres.valve (OFF)

Open Hi-pres.valve

available in the cooling system.

Cylinder valve (ON)

5) Make necessary repairs (tightening) if leak-

age is observed.

R134a

Compressor

Fluorine cylinder

ZX215-1002158

4-146

Structure and Function

5. Refrigerant charging operation

Ɣ When evacuation is finished, add refrigerant into the cooling system as per the following in-

struction:

75cm-Hg or more

More than 15 min.

Wait 5 min.

Pres. gauge

normal

Pres. gauge

Tighten pipe joint

abnormal

(1) Compressor stopped, charge at hi-press end

Check leak point

(2)Compressor running, add at lo-press end

Charge at the hi-pressure side

Valve

Remove the green hose of the manifold

OFF

pressure gauge from the vacuum pump

and connect it to the fluorine cylinder.

Loosen the cylinder valve and press the

Vent valve

vent valve on the gauge. Use the pressure

Open

Loosen

of the refrigerant to release the air in the

this nut

hose.

Blue

NOTE: Release the vent valve when you

Green

R134a

hear a hissing sound.

Red

To compressor

Fluorine cylinder

ZX215-1002159

CAUTION

Do not press the valve with naked hand

to avoid frostbite.

Open the hi-pressure valve of the manifold

Valve

A cylinder

pressure gauge and the cylinder valve with

(about 600g)

OFF

the engine stopped. Fill about 600g of re-

frigerant.

gDo not operate compressor

Lo-press.

gDo not open Lo-pressure valve

valve (OFF)

Close the hi-pressure valve of the pressure

Open Hi-press. valve

Fluorine cylinder

gauge and shut the cylinder valve.

valve (ON)

R134a

ZX215-1002160

4-147

Structure and Function

CAUTION

Ɣ Do not operate the compressor when

refrigerant charging is in progress.

Otherwise, refrigerant will counterflow

and cause the cylinder and hoses to ex-

plode.

Ɣ Operating the compressor with no re-

frigerant in the system will cause dam-

age to the compressor.

Ɣ Do not open the lo-pressure valve of the

manifold pressure gauge; otherwise,

the compressor will be damaged.

Charge at the lo-pressure side (refill)

1. Check that the hi-pressure valve of the

manifold pressure gauge is closed.

2. Start the engine.

Hi-press. valve (OFF)

Manifold pressure

3. Turn on the A/C unit. Adjust Temperature

gauge

control switch to minimum.

4. Adjust engine speed to 1300 - 1500 rpm.

Start the engine

5. Open the Lo-pressure valve of the mani-

1300~1500rpm

fold pressure gauge and the cylinder valve.

Add refrigerant until no foam is observed

ZX215-1002161

through the sight glass.

Remark:

Valve

When no foam

is observed

Manifold pressure gauge reading (for refer-

OFF

Lo-press. gauge

ence):

Hi-press. gauge

(1.5~2.5kgf/cm2)

(13~17kgf/cm²)

HIGH pressure:

Lo-press.

Hi-press. valve (OFF)

valve (ON)

(Never open it)

13~17kgf/cm² (when ambient temperature

Fluorine cylinder

is 30°C)

valve (ON)

LOW pressure:

1.5~2kgf/cm² (when ambient temperature

Compressor

Fluorine cylinder

running

is 30°C).

(never placed upside down)

ZX215-1002162

4-148

Structure and Function

6. When refrigerant charging is finished,

close the Lo-pressure valve of the mani-

fold pressure gauge and the valve of the

fluorine cylinder.

7. Check carefully for air leaks with a leak

detector.

CAUTION

Ɣ Opening the Hi-pressure valve of the

pressure gauge will cause pressurized

gas to counterflow and cause the hoses

and the fluorine cylinder to explode, re-

sulting in serious damage.

Ɣ When engine is running and charging in

progress, placing the fluorine cylinder

upside down will cause liquid refriger-

ant to be sucked directly into the com-

pressor and cause liquid compression,

resulting in equipment damage.

8. When ambient temperature is low

Valve

When refrigerant charging gets difficult

When no foam

OFF

is seen

OFF

due to low temperature, put the cylinder in

warm water (max. 40°C).

9. When ambient temperature is high

Lo-pressure

Hi-pressure valve

valve (ON)

(OFF)

When ambient temperature is very high,

Cylinder valve

(ON)

cool the compressor with an electrical fan.

Compressor

Water less than 40°C

running

(Do not use hot water)

ZX215-1002163

4-149

SANY Crawler Hydraulic Excavator (SY195C9, SY205C9, SY215C9, SY225C9). Shop Manual (2013) - page 12