Doosan B20S-3 User manual

Specifications
Systems Operation
Testing & Adjusting
MicroController Control System
Models : B20S-3 B25S-3 B30S-3
for Electric Lift Trucks
SB4082E00
Dec. 2002

1
MicroController Control System Specifications
Important Safety Information
Most accidents involving product operation, maintenance and repair are caused by failure to observe basic safety rules
or precautions. An accident can often be avoided by recognizing potentially hazardous situations before an accident
occurs. A person must be alert to potential hazards. This person should also have the necessary training, skill and tools
to perform these functions properly.
Improper operation, Iubrication, maintenance or repair of this product can be dangerous and could result in
injury or death.
Do not operater or perform any lubrication, maintenance or repair on this product, until you have read and
understood the operation, lubrication, maintenance and repair information.
Safety precautions and warnings are provided in this manual and on the product. f these hazard warnings are not
heeded, bodily injury or death could occur to you or other persons.
The hazards are identified by the “Safety Alert Symbol” and followed by a “Signal Word” such as “WARN NG” as shown
below.
The meaning of this safety alert symbol is as follows :
Attention! Become Alert! Your Safety is Involved.
The message that appears under the warning, explaining the hazard, can be either written or pictorially presented.
Operations that may cause product damage are identified by NOT CE labels on the product and in this publication.
DAEWOO cannot anticipate every possible circumstance that might involve a potential hazard. The warnings in this
pulication and on the product are therefore not all inclusive. f a tool, procedure, workmethod or operating technique
not specifically recommended by DAEWOO is used, you must satisfy yourself that it is safe for you and others.
ou should also ensure that the product will not be damaged or made unsafe by the operation, lubrication,
maintenance or repair procedures you choose.
The information, specifications, and illustrations in this publication are on the basis of information available at the
time it was written. The specifications, torques, pressures, measurements, adjustments, illustrations, and other
items can change at any time. These changes can affect the service given to the product. Obtain the complete and
most current information before starting any job. DAEWOO dealers have the most current information available.
ARNING

3
MicroController Control System Index
Index
Specifications
Component Measurements........................................5
Console......................................................................7
Contactor ...................................................................8
Control Panel (Layout) ...............................................9
Current Measurements..............................................5
Direction S itch.........................................................7
Display Layout............................................................7
Fuses.........................................................................8
H2/HP Technical Specifications .................................5
Instrument Panel........................................................7
MOSFET Connections...............................................6
MOSFET Measurements...........................................6
Thermal Senders-Control Panel ................................8
System Operation
Accessory Circuits ...................................................22
DC-DC Converter Circuit .....................................22
Horn Circuit..........................................................22
Hour Meter Circuit................................................22
Actuation Circuit.......................................................25
Description of Connectors........................................23
Drive Circuit .............................................................31
Bypass Circuit......................................................36
Control Circuit......................................................31
Current Limit........................................................35
Electrical Braking (Regenerative and Plugging) ..37
Flyback Cicrcuit....................................................34
Po er Circuit........................................................32
General Information .................................................16
Glossary...................................................................10
Hydraulic Pump Circuit ............................................26
Flyback Cicrcuit....................................................29
Lift Circuit.............................................................27
Lift Control Circuit................................................30
Po er Circuit........................................................28
Po er Steering Circuit .........................................26
Location of Control Panel Components ...................15
Operational Circuit Elements....................................17
Battery Discharge Indicator (BDI)........................21
Central Vehicle Monitoring System.......................17
Chat (Wait) Mode .................................................20
Contactor..............................................................20
CVMS International Pictorial Symbols..................19
“On Board” “Run Time”
Diagnostics(Fault Detection) ................................17
Shunts..................................................................20
Symbol Library.........................................................14
Thermal Protection Circuits......................................40
Control Panel .......................................................40
Drive Motor...........................................................40
Hydraulic Pump Motor..........................................40
Testing And Adjusting
Alarm Displayed on
the Console & Instrument Panel...............................46
Analysis of ALARMS Displayed on the Console......47
Component Tests ...................................................100
Conductor and S itch Continuity.......................100
Contactor ...........................................................101
Control and Po er System Operation Checks.........45
Digital Console.......................................................105
ADJUSTMENTS : Adjust Battery.......................112
ADJUSTMENTS : SET BATTERY TYPE ...........111
Description of ALARMS Functions.....................116
Description of PARAMETER CHANGE Menu.....119
Description of PROGRAM VACC Function........113
Description of RESTORE PARAM. Function......118
Description of SAVE PARAM. Function..............117
Description of SET OPTIONS Functions...........109
Description of Standard Console Menu.............107
Description of TESTER Functions .....................114
Ho to use the PARAMETER CHANGE Menu......122
Ho to use the TESTER Functions....................115
PARAMETER Settings.......................................121
Using Digital Console.........................................106

4
MicroController Control System Index
Electrical System Adjustments...............................102
Accelerator Control Linkage ..............................102
Lift Sensor..........................................................103
Parking Brake S itch.........................................102
Tilt and Auxiliary S itches Adjustment..............104
Valve Control Card Adjustment..........................103
LED Diagnosis for Drive controller...........................47
Preparation Tests and Checks .................................41
System Tests and Adjustments................................96
Discharge Head Capacitors.................................96
Logics Removal....................................................97
“Run Time” Tests ..................................................99
Test Equipment ....................................................96
Quick Diagnostic Mode............................................44
Troubleshooting........................................................41
Troubleshooting Problem List.............................52~95

5
MicroController Control System Specifications
Specifications
Component Measurements
H2 / HP Technical Specifications
Motor Types : ...................................................................................................DC Series Traction + DC Series Pump
Power ratings : Traction.....................................................................................................................................13.5k
Pump ........................................................................................................................................11.0k
Supply Voltage : ....................................................................................................................................................48V
Traction Motor Switching frequency : .................................................................................................................18kHz
Pump Motor Switching frequency : ....................................................................................................................18kHz
Temperature range : ............................................................................................................................-30˚C to + 40˚C
Maximum Controller temperature : .......................................................................................................................85˚C
Current Measurements
Component Meter
Scale Meter Positive (+) Test Lead Meter Ne ative (-) Test Lead Desired Indication
CONTACTOR COILS (resistance Indication)
Line, Bypass 200 X Y 90 to 110 ohms
Directional, Regen 200 X Y 60 to 80 ohms
48V SYSTEM CURRENT VALUES (AMPS)
Maximum Traction Motor Current Maximum Pump Motor Current
650 ± 5 % 600 ± 5 %

6
MicroController Control System Specifications
MOSFET Connections
1. Gate 2. Drain 3. Source
22
123
3
1
MOSFET Measurements
SPECIFICATIONS
Multimeter Setting (+) Test Lead (-) Test Lead Results
Resistance Gate Source Over 20 Mohms
Resistance Gate Drain Over 20 Mohms
Resistance Drain Source Over 20 Mohms
Resistance Drain Gate Over 20 Mohms
Resistance Source Gate Over 20 Mohms
Resistance Source Drain Over 20 Mohms
Diode Drain Source 0.4 ~ 0.7V

7
MicroController Control System Specifications
Display Layout
Instrument Panel
(1) Tighten screws that fasten the instrument panel to
a torque of
................................... 0.5 to 0.7
N • m (4 to 6 lb • in)
1
Console
(1) Tighten bolts that fasten the cover to a torque of
...............................1.5 to 2.5
N • m (13 to 22 lb • in)
Direction Switch
(1) Torque bolts that hold bracket to steering
column to................2.8 to 3.4
N • m (25 to 31 lb • in)
(2) Torque bolts that hold bracket to switch to
...............................3.4 to 3.9
N • m (31 to 35 lb • in)
1
12

8
MicroController Control System Specifications
Thermal Senders - Control Panel
Thermal protection at..............................80 °C (176 °F )
Contactor
Torque for nuts that hold contactor bridge
assembly.........................................2.2
N • m (20 lb • in)
Fuses
Traction ................................................................675A
Pump....................................................................400A
Key.........................................................................10A
Horn.......................................................................10A
DC / DC Converter.................................................10A
Light.......................................................................10A
Option light.............................................................10A

9
MicroController Control System Specifications
(1) Use a backup wrench to hold bolts and tighten
nuts the fasten bus bars and cables to a torque of
.....................................4 to 6
N • m (36 to 54 lb • in)
(2) Tighten screw that fasten the controllers to heatskin
to a torque of
.....................................2 to 4
N • m (18 to 36 lb • in)
(3) Use a backup wrench to hold bolts and tighten
the nuts that fasten the cables or bus bars to a
contactors to a torque of
.....................................4 to 6
N • m (36 to 54 lb • in)
(4) Tighten screw that fasten the contactors to
backplate to a torque of
.....................................2 to 4
N • m (18 to 36 lb • in)
(5) Apply sealant (Loctite cataloge No. & name No. 242,
Adhesive/Sealane) on the bolts used to tighten the
heatskin to the control panel to a torque of
................................10 to 14
N • m (90 to 125 lb • in)
(6) Control panel plate. Apply a small amount of
D557047 Thermal Joint Compound on control
panel plate and mating surface prior to assembly.
Control Panel (Layout)

10
MicroController Control System System Operation
Systems Operation
Glossary
NAME DESCRIPTION
Accelerator A device that converts mechanical movement into a analog voltage
pattern to the logics for variable drive motor speed.
Activate Word used with a component or circuit. To change from the normal condition
to the “activated condition because of an application of force or electricity.
Ammeter An electric meter used to measure current flow in amperes.
Ampere (or Amp) The unit of measurement of current flow. The amount of current that one
volt can push through a resistance of one ohm.
Analog to Digital Converter A device that converts an analog voltage into a pattern of digital HIGH and
LOW voltage signals.
Anode The positive (+) side of a diode.
Armature The rotating portion of an electric motor or generator.
Battery Two or more cells connected together for a supply of electric current.
BDI Battery Discharge Indicator - An electrically controlled display showing the
operator the state of battery charge.
Brush A conductor, normally a block of carbon, that makes sliding contact
between the stationary and moving part of the motor or generator.
Bus Bar A heavy electrical conductor to which other smaller wires are connected.
Capacitor Device used to store electrical energy for short periods of time.
Cathode The negative (-) side of a diode.
CVMS Central Vehicle Monitoring System.
Circuit A way for current to go from the positive (+) side of an electrical power
source to the negative (-) side of an electrical power source. This can be
through wires and electrical components.
Coil A component made from many circles or turns of wire used to concentrate
a magnetic field.
Commutator An armature component used to transfer current from the brushes to the
armature windings.
Conduct To allow the flow of current.
Conductor A material that provides a path for current flow.
Connector Part of a wire assembly or harness that connects with another wire
assembly or harness. Used for ease of assembly and disassembly.
Contactor Assembly An electrical component consisting of an electromagnetic coil and a set of
heavy contact tips. Control current passes through the coil, building a
magnetic field which closes or opens the contact tips.
Contactor Coil An electromagnet used to close or open contact tips in a contactor assembly.
Contact Tips or Contacts The portion of a switch, relay or contactor where the circuit can be opened
or closed.

11
MicroController Control System System Operation
NAME DESCRIPTION
Continuity Having the ability to allow current flow.
Control Circuits The wires and components carrying low current used to signal the logic
unit, turn on main components, or support auxiliary circuits (indicated by
narrow lines on a schmatic).
Counter Electromotive An opposing voltage set up by a collapsing or increasing magnetic field Force
(CEMF) within a coil.
Current The movement or flow of electricity through a conductor. A circuit must be
complete for current to flow.
Current Limit The maximum allowable armature current of a stalled drive motor during
pulsing.
Deactivate To change from the activated condition back to the normal (deactivated)
condition. It can be caused by the application of force, the removal of
force,or the removal of electricity.
Digital Signal A signal in which the elements may be either of two distinct values.
For example high voltage, low voltage.
Diode A semiconductor device that allows current to flow in one direction, from
the anode to the cathode.
Display An electrical device that converts voltage inputs to a visual output.
Drain The terminal of a MOSFET through which flow the main current.
Electrical Braking Electrically trying to rotate the drive motor opposite to the direction of
truck movement.
Electromagnet A coil of wire, most often wound on an iron core, which produces a strong
magnetic field when current is sent through the coil.
Electromotive Force (EMF) The force that causes an electric current to flow in a circuit. This force is
measured in volts.
Field Windings The stationary coils that produce a magnetic field in motors and generators.
Filter An electrical device or component for restriction or suppression of
undesired voltage spikes.
Fuse A component in an electrical circuit that will open the circuit if too much
current goes through it.
Gate The terminal of a MOSFET through which control the main current.
Harness An assembly made of two or more wires that are held together.
Heat Sink A mounting frame used for semiconductor cooling.
Hour Meter An electrically activated device used to record the amount of usage a
truck receives.
Indicator LCD that gives an indication of some vehicle condition when it turns on or
flashes.
Input A voltage change at the incoming connection of a component.
Insulator A material that has a very large resistance so that it will not let current flow
through it.
LCD Liquid Crystal Display.

12
MicroController Control System System Operation
NAME DESCRIPTION
Logics or Logic Unit The main printed circuit board containing a microprocessor and circuits to
condition the voltage signals that go into or come out of the logics.
It electronically monitors and controls the truck's functions.
Magnetic Field The area around a magnet where magnetic forces can be detected.
Microprocessor A small computer chip preprogrammed to control the various electrical
functions on a lift truck.
Normal Condition Words used with a switch or relay. Their normal condition is their
condition when they are not controlled by the application of force,
temperature, pressure, or electricity.
Normally Close (N.C.) A switch or relay whose contacts are closed in the normal condition.
Normally Open (N.O.) A switch or relay whose contacts are opened in the normal condition.
MOSFET A semiconductor component used in electric lift trucks as an electronic
switch. A MOSFET most often has three terminals, a GATE(G), a
DRAIN(D), a SOURCE(S). A MOSFET is a voltage-controlled device and
required only a small input current. The switching speed is very high.
OFF-Time The amount of time current does not flow through a transistor.
Ohm The unit of measurement of resistance. The amount of resistance that will
let one volt push only one ampere of current through it.
ON-Time The amount of time current flows through a transistor.
Open Circuit Wiring or components of a circuit that have no continuity.
Output The current flow from a component which initiated from a voltage change
at the component's input.
Overload The presence of voltage or current which is greater than an electrical
circuit or component is designed to handle.
Pin The male contact of a connector that fits into a female contact (socket) of
another connector.
Plugging A portion of electrical braking where the generated current is directed
back through the armature.
Plugging Current Limit The maximum allowable current at the drive motor armature during the
plugging portion of electrical braking.
Power Circuits The main current carrying components and conductors (indicated by the
heavy lines on a schematic).
Pulsing Current flow in a circuit being turned on and off.
Relay An electrical component consisting of an electromagnetic coil and a set of
small contact tips. Control current passes through the coil, building a
magnetic field which closes or opens the contact tips. When the contact
tips are closed, low current can flow in a separate isolated circuit.
Resistor A component made of a material that has a specific resistance to the flow
of current.
Schematic A line drawing of an electrical or electronic assembly which uses symbols
to show individual components. It shows how the components, wires and
connectors function electrically.

13
MicroController Control System System Operation
NAME DESCRIPTION
Semiconductor Components such as, transistors, diodes, thyristors, etc. Having electrical
characteristics between a conductor and an insulator.
Series Wound Motor A motor in which the armature is connected in series with the field windings.
Short Circuit An electrical connection between two or more components that is not
desired.
Socket The female contact of a connector that slips over a male contact (pin) of
another connector.
Solid State Reference to semiconductor components or circuits that use semiconductor
components that have no moving parts, such as diodes and transistors.
Source The terminal of a MOSFET through which flow the main current.
Switch A component used to control an electric circuit . It can close or open a circuit.
Systems The electrical components, circuits, and connections that deliver power to
perform specific tasks.
Terminal An electrical connection point on an electrical component.
Thermal Switch A switch that activates at a set temperature.
Turn ON When an electrical component conducts current.
Varistor A component terminated across the horn connections to eliminate
voltage spikes when the horn is activated.
Volt The unit of measurement of electromotive force. One volt is the force
needed to make one ampere of current flow through one ohm of
resistance in a circuit.
Watt The unit of measurement of power. The amount of power used when one
volt pushes one ampere of current through a resistance of one ohm. The
result of amperes (current) multiplied by volts (voltage) is watts (power).
Wire A conductor used to provide a path for current to flow to and from
electrical components.
Wiring Diagram A drawing using visual representation of components the way they
actually look. It is used to show the locations of components and the
connections between them.
Zener Diode A special diode used to regulate voltage or as an overvoltage (too high a
voltage) protector.

14
MicroController Control System System Operation
Symbol Library
234
1
19 10
1
11 12
7
8
9
13
14
15
17
18
5
ARM.
P10-10
Schematic Symbols
(1) MOSFET (2) Shunt (3) Thermal Sender (4) Thermal Switch (5) Battery
(6) Resistor (7) Diode (8) Normally Closed Contacts (9) Normally Open Contacts (10) Armature
(11) Male Terminal of Connector(Pin) (12) Female Terminal of Connector(Socket) (13) Wire Connection
(14) No Wire Connection (15) Contactor Coil (16) Field Windings (17) Capacitor (18) Fuse (19)Switch

15
MicroController Control System System Operation
Location of Control Panel Components
MicroController Control Panel
(1) Controller-pump (2) Logic card(Logics) (3) Pump Fuse
< DRIVE >
7
8543
21
MicroController Control Panel
(1) Controller-drive (2) Logic card(Logics) (3) Line Contactor (4) Directional Contactor (5) Regen. Contactor
(6) Bypass Contactor (7) Drive Fuse (8) Key Fuse
< PUMP >
3
21

16
MicroController Control System System Operation
General Information
The MicroControl Panel is the control center and the
Logic Unit (logics) is the decision making part of the
MicroController System. The logics provide a self
contained Battery Discharge Indicator (BDI) with lift
interrupt and built-in diagnostic capabilities. The
battery charge state and Quick diagnostic are
monitored by the logics and displayed by the
Central Vehicle Monitoring System (CVMS) located
on the steer console.
NOTICE
Damage to all motors and control panels will
result. The motors and control panels are 48 volt
unit and must be operated at their designed
voltage. The voltage can not be changed
without changing motors and control panel.
The steering system is activated when the truck is
powered up and the line contactor closes. The truck
uses a combined power steering/hydraulic system
where the hydraulic fluid for steering is provided by a
DC series hydraulic motor, pump, and priority valve.
The traction motor and the hydraulic pump motor are
controlled by pulsing MOSFETS ON and OFF and
controlling contactor operation.
The speed and direction of the drive motor are
controlled by voltage inputs to and outputs from the
logics. Inputs to the logics are generated by the
accelerator control and direction switch. Outputs
from the logics control contactor coil and drive
MOSFET pulsing.
The drive circuit pulses MOSFET to provide travel
speed control up to 95% of full speed, after which the
bypass contactor close to provide full speed.
The drive circuit includes a failure protection circuit
which detects malfunctions of the drive power circuit,
a plugging circuit to provide electrical braking and a
current limit circuit to prevent excessively high
currents during MOSFET pulsing.
The speed of the hydraulic pump motor is controlled
by voltage and switch inputs to and outputs from the
logics. Outputs pulses the hydraulic pump MOSFET
The MOSFET pulse to control the speed of the
hydraulic pump motor. To provide full speed the
logics turns the MOSFET ON 100%. The hydraulic
pump system includes a failure protection circuit to
protect against malfunctions of the power circuit.
Thermal protection circuits are used on the
hydraulic pump motor, the drive motor and the
control panel to prevent permanent damage caused
by over heating.

17
MicroController Control System System Operation
Operational Circuit Elements
Central Vehicle Monitoring System
The Central Vehicle Monitoring System (CVMS) is
located on the steering console.
It is a self contained, solidstate instrument panel
with two seven segment liquid crystal displays,
warning and system condition segments.
The LCD consists of seven segments which are
turned on or off to form numbers and letters.
Seven Segment Display Layout
The Central Vehicle Monitoring System interacts
with the logics and failure detection circuits.
It functions as a battery discharge indicator (BDI)
and provides on-board diagnostic data on the
operational condition of the truck.
During normal operation it provides “Run Time
diagnostics, and during troubleshooting it provides
“Quick diagnostics.
On Board “Run Time” Diagnostics
(Fault Detection)
“Run Time diagnostics use letters and numbers on
the seven segment LCD portion of the CVMS,
International Pictorial Symbols and LCD to signal
both improper operating sequences and truck
circuit defects.
Display = “blank”
If just the seven segment LCD and Symbols go blank,
then the main line fuse has blow out or regen
contactor is not operated. See Troubleshooting
section for additional problems.
Display = “EE” Static Return to Off (SRO)
The logics has a Static Return to Off (SRO) circuit
which assures that the direction switch has been
returned to neutral and the accelerator returned to
the full up position after the key and seat switch are
closed. This safeguards against an accidental
actuation of direction and speed when an operator
resumes operation of an idle truck.
If SRO occurs, the direction lever can be moved to
neutral and the accelerator pedal released.
The direction can now be reselected and the
accelerator pedal depressed to start normal lift truck
drive operation.
Display = “EE” (Flashing) Seat Circuit Problem
Anytime the battery is connected, the key is turned
to ON and no one is in the seat longer than 4 seconds
the letter “EE will flash on and off. The truck will not
operate until the seat switch is closed.
Display = “E1” Drive & Pump Motor Brush Problem
The logics monitor the length of the brush in the
drive pump motor. As the brush wear, a brush spring
moves down and makes contact with the brush
holder. A wire from a brush holder is connected to
the logics. If brush wear down to a preset limit, an
“E1 will appear on the LCD.
Display = “EC” Drive Controller Over Temperature
The drive logic monitors the temperature of the drive
controller. If the controller overheat(85°C), the logic
will reduce drive speed, the truck acceleration will
decrease, and “EC will appear on the LCD with
symbol.

18
MicroController Control System System Operation
Display = “Ec” Pump Controller Over Temperature
The pump logic monitors the temperature of the pump
controller. If the controller overheat(85°C), the logic
will slow lifting speeds and “Ec will appear on the LCD
with symbol.
Display = “Ed” Drive Motor Over Temperature
The drive logic monitors the temperature of the drive
motor. If the drive motor overheat(150°C), the logic
will reduce drive speed & acceleration and “Ed will
appear on the LCD with symbol.
Display = “Ep” Pump Motor Over Temperature
The pump logic monitors the temperature of the pump
motor. If the pump motor overheat(150°C), the logic
will reduce lifting speed and “Ep will appear on the
LCD with symbol.
Display = “A” Head Capacitor
The head capacitor ensures that a steady voltage is
maintained to the positive heatsink and that large
voltage spikes are filtered out. The logics monitors
this. If the logics detects that the head capacitor has
failed, an “A will be displayed and truck
performance will be reduced.
Display = “EL” Battery Lock-out
When the battery is discharged, the CVMS displays
“EL and pump motor will not operate. If key switch
turn off and then on, pump will operate for only 5
seconds. Drive motor speed will not exceed 70% of
the max. regardless of an accelerator’s output voltage.
Display = “F” Logic Board Failure
The logics can detect some internal crcuit failures.
When a failure is detected an “F will appear on the
display.
Display = “F0-F7”, “FA”, “Fb”, “Fc”, “FF”, “FL”
Failure Protection Circuits
The Failure Protection Circuit guards against a
condition which could cause the operator to lose
control of the lift truck. If one of the failure protection
circuits is activated, the display will appear the letter “F
and a number. The logics will prevent normal
operation of the lift truck.
Display = “F0” Overcurrent in Drive System
The logics monitors the drive motor current via the
shunt and compares the amount of current measured
to the current levels set on logic. If current exceeds
these levels for longer than a preset time. the logics
will shutdown, and an “F0 will appear on the display.
Display = “F1” Accelerator Problem
The logics monitors the output voltage from the
accelerator. If these signals do not appear the “F1
will appear on the display and the truck will shutdown.
Display = “F2” Drive Armature Circuit Failure
The logic monitors the voltage at S2 terminal(VMS) of
Drive system and Drive Armature current through
Shunt in controller. If the voltage is abnormal or the
current is too high, the logic will deactivate the Regen
contactor and an “F2 will appear on display.
Display = “F3” Pump System Failure
The logic monitors the voltage at P2 terminal of
Pump system and Pump current through Shunt in
controller. If the voltage is abnormal or the current is
too high, the logic will deactivate the Regen contactor
and an “F3 will appear on display.
Display = “F4” Drive & Pump System Failure
If the failures occur on both “F2 and “F3 , the
logic will deactivate the Regen contactor and an “F4
will appear on display.
Display = “F5” Drive Armature Circuit Failure
The logic monitors the Drive Armature current
through Shunt in controller. If the current is zero, the
logic will deactivate the Regen contactor and an “F5
will appear on display.
Display = “F ” Pump System Failure
The logic monitors the Pump current through Shunt in
controller. If the current is zero, the logic will deactivate
the Regen contactor and an “F6 will appear on display.
Display = “F7” Drive & Pump System Failure
If the failures occur on both “F5 and “F6 , the
logic will deactivate the Regen contactor and an “F7
will appear on display.

19
MicroController Control System System Operation
Display = “FA” Regen Contactor Failure(Closed)
If the Regen contactor is not opened in running, “FA
will appear on the LCD, and all contactors will not be
operated.
Display = “Fb” Battery Mismatch
If the battery voltage is lower than 40 volts or higer
than 60 volts, the logic will deactivate the Regen
contactor and an “Fb will appear on display.
Display = “Fc” Line Contactor Failure
If the coil of Directional contactor or the coil driver in
logic is failed, the logic will deactivate the Regen
contactor and an “Fc will appear on display.
Central Vehicle Monitoring System
(CVMS) International Pictorial
Symbols
Park Brake Symbol
Park Brake Symbol
If the park brake is applied, the park brake symbol
will turn on to warn the operator that the brake is
applied, and drive operation will be prevented.
Overtemperature Symbol
Normally closed thermal switches are in drive and
pump motors constantly monitored by the logics and
the CVMS. All these thermal switches are normally
closed, so must open for the LCD to turn on.
Truck performance will automatically be cut back by
the logics, and the CVMS will light the LCD until the
component cools.
Control Panel Overtemperature Symbol
Control Panel Overtemperature Symbol
Two thermal senders (Drive and Pump Module) are
connected to the logics. If any of the control panels
overheat(85°C), the logics will slow lifting speeds and
reduce drive speed. Truck acceleration will decrease.
The overtemperature symbol and “EC or “Ec will
appear on until the controller cools.