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8/3/2019 02 6 Electrical System
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KT403306Slide 1
Estructura y Funcin
Sistema Elctrico
E. Velsquez
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KT403306Slide 2
WA380-6 Electronics System
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KT403306Slide 3
WA380-6
ElectronicsOverview
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KT403306Slide 4
Slow Blow Fuses
Emergency steeringpump motor relay
Battery relay
Preheatingrelay R11
Fuse for ribbonintake air heater
Fuse for permanentpower supply
Fuse for main power
supply
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KT403306Slide 5
Starter Motor and Safety Relay
Starter motor 24 Volt, 5,5 kW
Safety relay
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KT403306Slide 6
Engine Control Module ECM
The ECM is mounted on the engine on acooler plate.
NOTE:
There is NO fuel flow through the plate onthe WA380-6
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Hydraulic Oil Temperature Sensor
The hydraulic oil temperature sensor R47 ismounted inside the right front of the rear
frame
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Relays, Fuses and Controllers
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Behind the Operator Seat
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Under the Operator Seat
Diodes under the operatorseat frame
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Accelerator Pedal
Electric accelerator pedal with potentiometerand idle validation switch
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Centralized Connectors under the Cabin
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WA380/480-6
How to read the new electrical diagrams
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Electrical Diagram Information
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Schematic Information
Wire color code legend
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Failure code [b@CENS] (Torque converter oil: Overheating)
Starting with a failure code
1. Check causes
2. Two different connectors are used, on one we need tomeasure resistance on the other we will measure voltage
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Connector Locator
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Circuit diagram for T/C oil temperature sensor
Pin 2 Betweenpin 1 & 2
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Starting Switch Circuit
New symbol for key switch
Switch terminals B, BR, R1, ACC are all connected when pre-heat is used
Switch terminals B, BR, and ACC are all connected when the switch is in the on position
Switch terminals B, BR, R2, C, and ACC are all connected when the switch is held in thestart position
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Starting Switch Circuit
New symbol for key switch
Wire for C terminal is circuit 105, wire size 1.25, fg =flexible wire with GREEN insulation
Is connected to pin 3 of male half of connector S40 whichis a DT type connector
from the female half of S40 wire number 105 goes to pin12 of connector J07
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KT403306Slide 21
Starting Switch Circuit
New key switch circuit
Connector J07 is a M type connector
Pin 12 is also common with pins 11 and 13
Circuit 105 now becomes circuits 105 A and105B
Circuit 105B goes to connector TEL pin 7
Circuit 105A goes to connector L44 pin 4
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KT403306Slide 22
Starting Switch Circuit
Wire 105A comes from pin 11 of connector J07 this wirechanged color at connector J04 to white with a blue stripe
Wire 105A for this application is terminated at connector L44
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KT403306Slide 23
Starting Switch Circuit
Wire 105B from connector J07 13 to TEL pin 7 this wire color wasunchanged
Connector TEL pin 7 female side is now circuit 105 AB
Wire 105 AB goes to connector L80 pin 27 and connector W60 pin 3
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KT403306Slide 24
Starting Switch Circuit
Circuit number on W60 haschanged 105AB to 105AA
This wire comes fromconnector L80 pin 27
A second wire on 105AAcomes from TEL pin 7
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KT403306Slide 25
QUIZ
Electrical Circuit of Hydraulic Oil Temperature Sensor
Find the hydraulic oil temperature sensor R47.
The signal line on pin 1 is connected to pin 41 on the next connector FL1.
The ground line on pin 2 is connected through the remaining pins to ground.
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KT403306Slide 26
Electrical Circuit of Hydraulic Oil Temperature Sensor
On the FL1 connecter you will find pin 41 and the connecter name R47 of the hydraulic oiltemperature sensor.
Now find the opposite part of FL1 connector in the schematics.
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KT403306Slide 27
Electrical Circuit of Hydraulic Oil Temperature Sensor
The opposite part of FL1 connector provides the following information:
Connecter L55 is the next connector you you have to look for in the schematic.
The hydraulic oil temperature will be inputted on pin number 7 of the next connector.
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KT403306Slide 28
Electrical Circuit of Hydraulic Oil Temperature Sensor
The line arrives at connecter L55 on the monitor panel.
The line comes from connector FL1 pin 41, which was the last connector in this case.
The hydraulic oil temperature signal is an input on pin 7 of the main monitor.
Monitor Panel Controller
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KT403306Slide 29
CONNECTOR LOCATOR CHART
Connector Locator Chart
C
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KT403306Slide 30
Connector Locator
C L
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KT403306Slide 31
Connector Locator
C L
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KT403306Slide 32
Connector Locator
C L
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KT403306Slide 33
Connector Locator
C t L t
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KT403306Slide 34
Connector Locator
C t L t
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KT403306Slide 35
Connector Locator
C t L t
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KT403306Slide 36
Connector Locator
C t L t
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KT403306Slide 37
Connector Locator
WA380/480 6 M it S t
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KT403306Slide 38
WA380/480-6 Monitor System
Machine Monitors
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KT403306Slide 39
In the machine monitor system:
Each controller on the network monitors and controls the machinecondition with the sensors and switches installed in varioussystems on the machine
These controllers then send their acquired information as networkinformation to the machine monitor
The machine monitor displays this information to notify theoperator of the machine condition.
WA380/480-6 Monitor System
The machine monitor can displays thisinformation in either the operator mode or
service mode.
WA380/480 6 Monitor System O t M d
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KT403306Slide 40
WA380/480-6 Monitor System Operator Mode
The operator mode is used to display the normal information
to the operator.The major functions used in the operator mode are as follows.
Items always displayed1. Meters (Speedometer or engine tachometer)
2. Gauges (Engine coolant temperature gauge, torque converteroil temperature gauge, hydraulic oil temperature gauge, and fuellevel gauge)
3. Pilot indicators4. Service meter
The following items are displayed according to the setstate of the optional device selecting function.1. Travel speed or engine speed indicationon the character display
WA380/480 6 Monitor System
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KT403306Slide 41
WA380/480-6 Monitor System
Items displayed when a abnormality is detected
1. Caution lamps2. Action code (While an action code is
displayed, press the monitor panel modeselector switch (>) To display the failure code(6 digits).))
WA380/480 6 Monitor System
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KT403306Slide 42
WA380/480-6 Monitor System
At service interval time for filters or oil changesThe character display displays that filter or oilchange information.(Maintenance monitoring function)
Also: the following display, setting and adjustment functions are provided byusing the character display and the machine monitor mode selector switch1) Display the odometer2) Reset maintenance interval time3) Input a telephone number
4) Select your language5) Adjust machine monitor brightness6) Travel speed/engine speed display selecting function7) Function for setting display/no-display of travel speed or engine speed to thecharacter display
See shop manualSEN01229-0 page 6
WA380/480 6 Monitor System
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KT403306Slide 43
WA380/480-6 Monitor System
The service mode function is provided to aid in successfultroubleshooting of all monitored parameters for eachcontroller on the network(including the machine monitor itself).
The major functions used in the service mode are as follows.1. Electrical system failure history display function2. Mechanical system failure history display function3. Real-time monitoring function: The input and output signals recognized byeach controller on the network are displayed in real time.4. Engine reduced-cylinder function
5. No injection cranking function6. Adjustment function: functions are provided to correct/adjust installation errors,manufacturing dispersion of the sensors, solenoid valves, etc.
7. Maintenance monitoring function: to changes filter or oil service intervals, alsocan switch the maintenance function on or off
Service Mode
WA380/480 6 Monitor System
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KT403306Slide 44
WA380/480-6 Monitor System
8. Operating information display function: Displays fuel consumptionper operating hour.9. Optional device selecting function: Verifies the installation of optionaldevices or changes their setting.10Machine serial number input function: Enters the machine serialnumber to identify the machine.
11. Model selection function: Enter the information of applicable model.12. Initialize function: This function is used to set the machine monitorto the state set when the machine is delivered.
WA380/480 6 Monitor System
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KT403306Slide 45
WA380/480-6 Monitor System
Items displayed on monitorCondition for judging that engine is running: When either one or both of following
items 1 and 2 is or are sensed, the machine monitor judges that the engine isrunning.1. The engine speed is above 500 rpm.2. There is alternator voltage R and there is terminal C input after the startingswitch is turned ON.O: ON
: Flashing (1.6 sec., 50% duty): : Intermittent (Period: 240 msec., ON: 80 msec., OFF: 160 msec.): As per separate setting conditionPriority of sounding of buzzer: Continual (w) > Intermittent (A) > Cancellation ofoperation > Check of acceptanceof operation.
WA380/480 6 Monitor System MONITOR INFORMATION
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KT403306Slide 46
WA380/480-6 Monitor System - MONITOR INFORMATION
See shop manualSEN00886-00page 8
WA380/480 6 Monitor System
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KT403306Slide 47
With key switch off press to view service meter
WA380/480-6 Monitor System
To move from operator mode to servicemode; press and hold the left arrow keyand the box key for 5 seconds, releasethese keys when the monitor informationscreen changes.
You will be prompted to enter yourpassword
WA380/480-6 Monitor System
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KT403306Slide 48
WA380/480-6 Monitor System
Failure code screen (1st layer)1. Pressing the > switch when the Warning screen is on display
changes display to the Failure code screen.2. If multiple failure codes are present, each pressing of the >
switch displays them from the item of higher priority downward. Ifitems have the same priority, the item that occurred most recentlywill be displayed first.
Note: there are 3simultaneouslyoccurring failurecodes.
1. from the
transmissioncontroller
2. from the enginecontroller
3. from the monitor
WA380/480-6 Monitor System
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KT403306Slide 49
WA380/480-6 Monitor System
Functions available to the operator(2nd layer or below)
Pressing switch enables to selecteach menu.
See the Operation and maintenancemanual for details of each menu.
WA380/480-6 Monitor System
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KT403306Slide 50
Procedure for switching to Service Mode1. Check that the character display is set to the 1st layer screen in
the operator mode.2. Display of ID input initial screen Pressing switch and and enter ID. (ID: 6491)
WA380/480-6 Monitor System
C
C
Pressing the < > keys changes the value of this digit in therange of 0 to 9 one number at a time. Pressing the key willaccept the integer that you entered. If you have entered anincorrect integer pressing the will take you back one step.
WA380/480-6 Monitor System
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KT403306Slide 51
WA380/480 6 Monitor System
WA380/480-6 Transmission Control System
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WA380/480 6 Transmission Control System
See shop manual SEN00887-00 page 3-7 toreview auto shift logic
WA380-6
WA380/480-6 Transmission Control System
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KT403306Slide 53
1. Shift hold function: maintains the gear speed chosen when the auto shift
mode is used.2. Hold function does not allow shifting up or down as the travel speed is
changed (up/down).3. Pressing the hold switch again resets the shift hold function and turns off the
pilot lamp.4. The shift hold function is automatically reset when the directional lever, gear
shift lever or kick-down switch is operated.5. The torque converter lockup is turned off.
Kick-down function1. In manual-shift mode
When the directional lever is set to F and the gear shift lever to 2nd, pressingthe kick-down switch changes the gear speed to 1st.2. The kick-down signal is ignored in either R or N or in any gear other than 2nd
3. Kick-down is reset when the directional lever is operated or the gear shift leveris set to any position other than 2nd.
WA380/480 6 Transmission Control System
WA380/480-6 Transmission Control System
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KT403306Slide 54
Kick- down functionIn auto-shift mode
1. The kick-down function is enabled when the directional leveris set to a position other than N (Neutral) and the gear shift
lever is set to a position other than the 1st position.2. The kick-down function is reset when the directional lever is
operated after the actual gear speed is changed or the no-shift time for hunting prevention elapses.
3. After the reset, the auto shift based on Auto-shift pointstable is turned on.
When forward 1st is selected1. When E-mode is selected for the power mode and the gear speed is set
to forward 1st, pressing the kick-down switch changes the power mode to P-mode.2. The power mode switching function is enabled, independent of the auto ormanual shift, only when forward1st is selected and it is reset as any actualgear speed other than 1st is selected.
WA380/480 6 Transmission Control System
WA380/480-6 Transmission Control System
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KT403306Slide 55
Function of hunting prevention1. The transmission controller detects and prevents hunting that can
result from shifting the gear from 2nd to 3rd and 3rd to 2nd in the autoshift mode.
Transmission initial learning and ECMV current adjustment1. Adjusting the Transmission initial learning setting and Transmission
ECMV current adjustment items by use of the adjustment function of
the machine monitor allows correcting variations of the transmissionitself as well as ECMV.2. Ignoring above adjustment can lead to generation of gear shiftingshocks or time lag.
Changing shift points
1. The transmission controller has the function of adjusting the gear shift pointsof L-mode in auto-shift.2. When hunting is induced by some conditions unique to a worksite, adjust theshift up and down travel speeds by adjusting the Adjustment of transmission L-mode shift point item by use of the adjustment function of the machine monitor.
WA380/480 6 Transmission Control System
WA380/480-6 Transmission Control System
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KT403306Slide 56
4th gear lockout function1. Restriction of operation in 4th gear speed becomes available by
selecting ADD for 23. FORBID 4TH item using the optional deviceselecting function of the machine monitor.
Transmission controller will protect the transmission when an on authorizeddirectional shift is selected1. When the directional lever is operated during high-speed travel (3rd/4th),
engagement of the speed clutch is controlled to protect the transmission.
WA380/480 6 Transmission Control System
WA380/480-6 Transmission Control System
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KT403306Slide 57
Shift down protection
1. In order to protect the engine and pumps, the transmission controllerrejects a downshift command when travel speed is to great
2. The alarm buzzer is sounded as long as the shift down protectionfunction is turned on.
3. The buzzer sounds are continued until the gear speed position of thegear shift lever coincides with the actual gear speed. Thus, shifting upoperation can stop the alarm buzzer sounds even if the travel speed isnot slowed down.
4. The shift down protection rejects the kick-down signal when the travelspeed is to great.
5. If the kick-down switch is pressed while the machine is traveling to fast
the alarm buzzer will be sounded for 3 seconds.
WA380/480 6 Transmission Control System
WA380/480-6 Transmission Control System
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KT403306Slide 58
Engine overrun prevention1. When the transmission output shaft speed reaches a level that corresponds
to an engine RPM of 2,500 rpm or greater, the lockup clutch is disengagedautomatically in order to prevent the engine overrun.
2. The alarm buzzer is sounded as long as the engine overrun preventionfunction is turned on.
3. The unlock state is maintained for 5 seconds after it has been determinedthat the engine speed is less than 2,500 RPM.
4. Lockup will than be applied again.
Maximum travel speed de-rate function1. As transmission output shaft speed reached a level corresponding to a travel
speed of 40 km/h or above, this function resets the lockup for safety.
2. The alarm buzzer is sounded as long as the maximum travel speed de-ratefunction is turned on.3. When the lockup clutch is not installed on the machine, alarm buzzer alone will
be sounded.
WA380/480 6 Transmission Control System
WA380/480-6 Monitor System
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KT403306Slide 59
Transmission cut-off function1. The transmission cut-off oil pressure sensor detects the brake pilot pressure
when either brake pedal is pressed and sets the transmission to neutral.2. This function will work at any brake pedal position, by saving the brake
pressure at any brake pedal angle into the transmission controller memory.
WA380/480 6 Monitor System
Transmissioncut-off control
See shop manualSEN0887-00page 26 forsettinginstructions
Outline As the transmission cut-off operating conditions are met, thetransmission is set to neutral.
As the transmission cut-off reset conditions are met, the transmission
is released and the transmission gear speed is controlled by themodulation.
Operatingcondition
Operating conditions in 1st and 2nd gear speeds
Cut-off switch is turned ON and the brake pilot oil pressure becamelarger than the cut-off IN pressure.
Operating conditions at 3rd and 4th gear speeds
Cut-off switch is turned ON and brake pilot oil pressure is larger thanthe cut-off IN pressure and the accelerator pedal is less than 30%
Resetcondition
When any of the following is met, cut-off is reset.
The transmission cut-off switch is turned OFF.
The brake pilot oil pressure is below the cut-off OUT pressure.
WA380/480-6 Engine Control System
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KT403306Slide 60
WA380/480 6 Engine Control System
Power mode selecting function1. Setting the power mode selector switch to P-mode sends the P-modetorque curve information to the engine controller. At the same time, thepower mode pilot lamp is turned on.
Engine stall prevention control1. When engine speed is at low idle, switching travel direction during high-speed
travel can cause the engine to stall.2. To prevent engine stall, a specified throttle (accelerator pedal) lower limit
position signal is sent to the engine controller as the travel direction is switched.3. When the direction was changed from reverse to forward, this function sends
as much as approximately 25% of the specified throttle lower limit positionvalues to the engine controller.
4. In the case of forward to reverse, as much as approximately 15% of thevalues are sent. This communication lasts for 2 seconds after the directionalselection is completed.
Engine Control Function
WA380/480-6 Engine Control System
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KT403306Slide 61
1. Transmission controller2. Machine monitor
3. Engine controller4. Cooling fan pump4a. Swash plate angle control EPC valve5. Cooling fan motor5a. Cooling fan reverse rotation solenoid valve6. Cooling fan reverse rotation switch
7. Machine monitor mode selector switch 18. Machine monitor mode selector switch 2
9. Hydraulic oil temperature sensor10. Torque converter oil temperature sensor11. Coolant temperature sensor12. Engine speed sensor13. Engine14. Radiator
380/ 80 6 g e Co t o Syste
Cooling Fan Control Function
WA380/480-6 Engine Control System
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KT403306Slide 62
Engine speed, coolant temperature, torque converter, and hydraulic
oil temperature received by the machine monitor are sent to thetransmission controller via the network.1. Based on the received information, the transmission controllersends current to the EPC valve on the cooling fan pump to control thepump swash plate angle to set fan speed to the desired speed
Pump protection function1. To prevent cooling fan motor overrun, fan pump swash plate angle is set tominimal when engine speed reached 2,300 rpm or above.2. If the transmission controller fails to recognize engine speed and temperaturedata because of communication error, this function sends (677mA) to the EPC
valve on the pump3. Now the pump will work as a fixed displacement pump.
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WA380/480-6 Hydraulic Control
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KT403306Slide 63
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Work Equipment Pump Swash Plate Control FunctionComparing results of calculations done on respective functions, this functionselects the data that makes the work equipment pump delivery smaller (the
data that sets a larger value for the command current to the swash plateangle control EPC valve).
Engine stall prevention control at low idle1. Engine stall can result from a radical increase in load at low idle.
2. To prevent this problem, this function restricts the pump delivery athigh pressure by controlling the pump swash plate angle throughEPC.
Hydraulic Pump Control
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WA380/480-6 Hydraulic Control
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KT403306Slide 65
Pickup auxiliary function when engine speed is low1. Using compound hydraulic operations and steering at a lowengine speed can cause poor engine acceleration because thehydraulic HP. Demand becomes larger than engine capability.2. This function is installed to help improve the engine accelerationperformance.
3. As the accelerator pedal is pressed from a low engine speed,this function sends the command current corresponding to thesteering oil pressure to the main pump EPC valve in order toalleviate the load by controlling the pump swash plate.
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Electrical System
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KT403306Slide 66
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Electrical System
WA380/480-6 Engine Start Circuit
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WA380/480-6 Engine Stop Circuit
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g p
WA380/480-6 Parking Brake System
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KT403306Slide 69
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1. Parking brake relay2. Parking brake switch3. Brake oil pressure caution relay4. Rear brake oil pressure switch
5. Emergency brake oil pressure switch6. Parking brake solenoid valve7. Transmission controller8. Machine monitor
When starting switch is turned OFF1. Turning the starting switch OFF opens brake
relay (1). Stopping current flow to the parkingbrake circuit, applies the parking brake.
2. Accordingly, when the starting switch is turnedOFF, current is not conducted to parking brakesolenoid valve (6) regardless of the position ofparking brake switch (2). And the parking brakeremains applied.
WA380/480-6 Parking Brake System
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KT403306Slide 70
When PB switch (2) is ON (applied), batterycurrent flows through PB switch (2), to parking brakerelay (1) and closes the contact. With PB relay (1) closed, battery current holds the
contact closed until current from the battery relay iscut off.
Current does not flow to parking brake solenoidvalve (6). The parking brake is applied. Transmission controller (7) responds to PBswitch (2) signal and sets the transmission to N
as long as the parking brake is applied.When PB switch (2) is OFF (released) currentfrom the battery goes from PB relay (1), to parkingbrake switch (2), to emergency brake oil pressureswitch (5) to parking brake solenoid valve (6) andrelease the parking brake.
WA380/480-6 Parking Brake System
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KT403306Slide 71
When parking brake switch was turned OFF (released)
before turning the starting switch ON
While the parking brake switch (2) is OFF (released),
current does not flow to parking brake relay (1) and itscontacts remain open.Turning ON the starting switch in this case does not
conduct current to parking brake solenoid valve (6). Accordingly, the parking brake is not released
WA380/480-6 Parking Brake System
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KT403306Slide 72
When low brake oil pressure is sensed If brake oil pressure gets low, rear brake oil pressureswitch (4) opens, cutting off current to caution relay (3). Brake oil pressure caution relay (3) opens, cutting off
current to machine monitor (8). As the result, machine monitor generates the alarm. Brake oil pressure switch (5) opens (the operatingpressure setting of which is lower than that of rear brakeoil pressure switch (4) stopping current flow to brakesolenoid valve (6). As the result, the parking brake is applied.
In this case, (unlike when the parking brakeswitch was turned ON (applied)), current flowfrom parking brake switch (2) to the
transmission controller (7) is maintained. Thus, transmission is not set to the neutral.
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End of Electrical System
Section 2_6