SANY Crawler Hydraulic Excavator SY215CLC (CUMMINS QSB6.7 engine). Shop Manual

Structure and Function

SY215C

4-188

4.9.6

Duo travel speed control

ZX215-1002203

ESC

Enter

Regulator

Travel motor

Main valve

Travel Speed
solenoid valve

L. Travel pressure sensor

R. Travel pressure sensor

Regulator

Main pump

Engine

Governor
motor

Servo

Fuel injection
pump

Controller

Monitor

(CAN

bus)

(Control signal)

(Throttle position feedback signal)

(Motor drive signal)

Fuel control dial

Structure and Function

SY215C

4-189

Function

●

Control travel mode.

Operating condition

●

When Hi speed travel mode on the monitor
is enabled.

Remark:

When one side of the tracks is lifted off the
ground by the work equipment and rotating,
pressure at one side of the pump increases,
which makes the lifted track rotate very fast.
When the machine is traveling under Hi speed
mode, even if work equipment is being op-
erated (work equipment pressure sensor is
switched ON), travel mode remains in Hi travel
mode.

Operation

●

When the travel mode is set at LO speed,
the swash plate angle of the travel motor is
the largest, and travel speed is low.

●

When the controller receives the signal
from the travel pressure sensor under the
conditions below, it activates the solenoid
valve. Then, the solenoid valve conducts
pilot pressure oil to the swash plate angle
control valve of the travel motor, and re-
duces the swash plate angle to increase
travel speed.

Structure and Function

SY215C

4-190

4.9.7

Engine preheating/overheating alarm

ZX215-1002204

Heat

ESC

Enter

Main valve

Start switch

Preheat s/w

Preheat relay

Coolant

tempe

sensor

Governor motor

Servo

Main
pump

Controller

Servo

Monitor

(CAN

bus)

Engine

(Control signal)

(Motor drive signal)

(Throttle position feedback signal)

Fuel control dial

Structure and Function

SY215C

4-191

Function

●

Preheating control

Operation

●

This function shall be used in combination
with the preheating switch located on the
right armrest. Turn the engine start key
counterclockwise to the HEAT position and
hold on, the engine will start preheating.
When released, the key will return to the
OFF position automatically and preheating
stops.

Operating condition

●

Power ON. Start key set at the HEAT posi-
tion.

●

Preheating switch: ON

4.9.7.1 Engine preheating

Structure and Function

SY215C

4-192

Function

●

When engine coolant temperature be-
comes excessively high (above 110°C)
during operation, overheating alarm on the
monitor display will light up.

Operation

●

The controller collects signal from the cool-
ant temperature sensor. When coolant
temperature rises too high, alarming infor-
mation will be generated and transmitted
to the machine monitor. The alarm lamp on
the display lights up when the monitor re-
ceives the signal.

Operating condition

●

Power ON.

●

Coolant temperature above 110°C.

4.9.7.2 Engine overheating alarm

Function

●

The engine controller collects signal from
the engine oil pressure sensor. When en-
gine speed exceeds 600 rpm, if oil pres-
sure is too low, alarming information will be
generated and transmitted to the machine
monitor. The alarm indicator lights up when
the monitor receives the signal.

4.9.8 Engine oil under

–

pressure alarm

Structure and Function

SY215C

4-193

4.9.9

Auto deceleration/acceleration control

ZX215-1002205

ESC

Enter

(

Throttle signal)

Engine
throttle
controller

Control lever signal

Controller

Monitor

(CAN

bus)

Engine

Fuel control dial

(

Motor drive signal)

(

Potentiometer signal)

Right joystick

Boom

Bucket

DOWN

OUT

Left joystick

Swing

Arm

CURL

DUMP

L.Travel

Travel lever

R.Travel

Forward Reverse

Forward

Reverse

Structure and Function

SY215C

4-194

Operation

●

Three seconds after all control levers are
neutralized, engine speed will drop to the

rst deceleration level about 100 rpm lower

than the set speed. After another 3 sec-
onds engine speed enters low speed (1350
rpm) to reduce the loss of the hydraulic
system and engine wear, and reduce fuel
consumption and noise. When the control
lever is operated again, the engine speed
rises instantly to the previous level.

●

If any control lever is operated while the
engine speed is kept at decelerated level,
engine speed will rise instantly to the level
set by the fuel control dial.

Function

●

If all the control levers are neutralized, en-
gine speed will drop to the medium level
automatically to reduce fuel consumption
and noise.

●

If any of the levers is operated, the engine
speed rises to the set level instantly.

ZX215-1002206

(1350rpm)

Drop

100rpm

Control lever

Operated

Unoperated

Operated

Set rpm

Time (second)

less than 2 S

Deceleration

Less than 1 S

Speed (rpm)

Structure and Function

SY215C

4-195

4.9.10

Engine speed calibration function

ZX215-1002207

LED

MEMORYON

DOWN

RPW

A/I

ESC

Enter

R. Travel signal

L. Travel signal

Boom UP signal

Boom DOWN signal

Arm IN signal

Arm OUT signal

Bucket DIG signal

Bucket DUMP signal

Swing signal

Calibtator

(CAN

bus)

Controller

Monitor

Fuel control dial

(Engine speed signaL)

(Control signaL)

(Motor drive signaL)

(Throttle position feedback signaL)

Engine

Speed

sensor

Main pump

Main valve

Bucket confluence

Swing pripority

Pressure sensor

Servo

Pressure sensor

Fuel injection
pump

Governor
motor

Structure and Function

SY215C

4-196

Function

●

Set the maximum engine speed under
each working mode. This set speed is the
standard to control engine speed.

Operation

●

Calibrating procedure for positive

ow ex-

cavators.

1) H, S, L maximum speed calibration, and A/

I speed calibration.

2) Turn the dial on the calibrator counter-

clockwise to the end

3) Power OFF

4) Set the calibrator to "Monitor mode", power

on and check the result.

Remark:

Memory SW up: Calibration mode;

Memory SW down: Monitor mode

Structure and Function

SY215C

4-197

4.9.11

System Components

4.9.11.1 Pump pressure sensor

Operation

●

The relationship between the pressure ap-
plied to sensors (P) and output voltage (E)
is shown in the

gure on the right.

ZX215-1002208

Terminal A

Terminal B

Terminal C

Pressure connector

Body

Connector

Connection diagram

No.

Signal name

Z direction

Grounding

Output

ZX215-1002209

(V)

5
5

(MPa)

Sensor output voltage (E)

Oil pressure (P)

Structure and Function

SY215C

4-198

4.9.11.2 Pilot pressure sensor

Operation

●

The relationship between the pressure ap-
plied to sensors (P) and output voltage (E)
is shown in the

gure on the right.

ZX215-1002208

Terminal A

Terminal B

Terminal C

Pressure connector

Body

Connector

Connection diagram

No.

Signal name

Z direction

Grounding

Output

ZX215-1002210

(V)

5
5

(MPa)

Sensor output voltage (E)

Oil pressure (P)

Structure and Function

SY215C

4-199

4.9.11.3 Engine speed sensor

Operation

●

Measure the resistance between terminal
1 and terminal 2 when it is in service.

Standard value (@25°C)

2.3±0.2 k

●

If the measured value exceeds the stan-
dard value, replace the sensor.

●

If the engine speed sensor is not tight-
ened to the specified torque, the sen-
sor may send out no signals. Tighten
the engine speed sensor to the speci-
fi ed torque.

Function

●

The engine revolution sensor is installed to
the ring gear of the engine

ywheel. It elec-

trically calculates the number of the gear
teeth which pass in front of it and transmits
the result to the engine controller.

ZX215-1002211

CAUTION

Structure and Function

SY215C

4-200

4.9.11.4 Coolant temperature sensor

1- Sensor
2- Connector

Function

●

The output resistance of the engine cool-
ant temperature sensor changes with the
coolant temperature. The controller collects
and processes coolant temperature signals
and works out the coolant temperature.

Standard

value

50°C

(Ref.)

60°C

56.3

80°C

29.5±10

100°C

16.5

106°C

14.3±0.5

120°C

(Ref.)

Specifi cations

ZX215-1002212

Structure and Function

SY215C

4-202

4.9.11.6 Oil pressure switch

1- O-ring
2- Sensor
3- Connector

Function

●

The oil pressure switch is installed on the
outlet circuit of the oil filter. It detects oil
pressure and transmits warning signals to
the controller.

Specifi cations

●

Type of contact: Normally closed

●

Operating pressure: 1.9kg

ZX215-1002214

Pressure

Electrical
diagram

Load

Structure and Function

SY215C

4-203

4.10

Monitoring System

ZX215-1002215

Sany Hydraulic Excavator

0000

00:00:00

00/00/00

ESC

Enter

CAN signal

Sensor

Engine
controller

Power source

Battery

Machine monitor

n/min

AUTO

●

The state of the machine is monitored
by the sensors mounted on the machine
components. The controller processes the
signals and transmits the signals to the
monitor display, informing the operator of
the machine condition.

●

Information on the monitor display includes
primarily:

1. Alert information when a machine fault is

detected.

2. Operating condition (coolant temperature,

fuel level, etc. )

●

The machine control system can be oper-
ated using the switches and keys on the
monitor panel.

SANY Crawler Hydraulic Excavator SY215CLC (CUMMINS QSB6.7 engine). Shop Manual - page 18