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.
Содержание B20S-3
Страница 3: ......