40
MicroController Control System
Systems Operation
Thermal Protection Circuits
Control Panel
If the MOSFETs overheat, a thermal senders
mounted in the MOSFET heatsink will give a voltage
signal to logic. If the temperature is over than preset
value(85
°C
)
, the Central Vehicle Monitoring System
will display a “Run Time” diagnostic symbol and EC
(or Ec). The logics will decrease the pulsing of the drive
system(EC) or restrict the hydraulic circuit
pulsing to 50%(Ec). The amount of current allowed to
flow through the MOSFETs is decreased to permit
them to cool. When the heatsink cools off the truck
will return to normal operation. But due to the reduced
pulsing, acceleration performance will be decreased.
This alarms are stored in memory.
Drive Motor
If the drive motor overheats a thermal switch
mounted in the drive motor will open at a
predetermined temperature(150
°C
)
. When it opens,
voltage at logic connection DE-2 will go LOW.
The Central Vehicle Monitoring System will display a
“Run Time” diagnostic symbol and Ed. To decrease
the amount of current allowed to flow through the
drive motor, the logics will reduce the pulsing. When
the drive motor cools off and the thermal switch
closes, the truck will return to normal operation.
Drive system acceleration performance is affected by
an overheated drive motor.
This alarm is stored in memory.
Hydraulic Pump Motor
If the hydraulic pump motor overheats a thermal
switch mounted in the pump motor housing will
open at a predetermined temperature(150
°C
)
.
When it opens, voltage at logic connection PE-1 will
go LOW. The Central Vehicle Monitoring System will
display a “Run Time” diagnostic symbol and EP. To
decrease the amount of current allowed to flow
through the pump motor, the logics will reduce the
hydraulic pump motor to 50% pulsing. When the
hydraulic pump motor cools off and the thermal
switch closes, the truck will return to normal
operation. This alarm is stored in memory.
Summary of Contents for B20S-3
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