Komatsu 830E-AC, Shop Manual

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E2-28 Electrical Propulsion System Components 10/06 E02020
Transition from Ready State to Retard State: This
transition will occur if truck speed is such that retard
is allowed and at least one of the following conditions
exists:
• Truck speed is greater than or equal to motor
overspeed limit. Overspeed will not be engaged
such that it prevents the truck from propelling at
40 mph (64 kph).
• The retard pedal or lever is pressed such that a
significant amount of retarding effort is
requested.
• All of the following conditions are true:
a. Retard speed control is selected.
b. Truck speed exceeds the set retard speed,
or the truck is accelerating such that the
truck speed will soon exceed the set retard
speed if no action is taken.
c. The accel pedal is not pressed and/or the
truck is configured such that accelerator
pedal signal does not override retard speed
control.
Transition from Rest State to Test State: This
transition will occur upon release of the TCI rest
request.
NOTE: A transition directly from Rest state to Ready
state is not allowed because the system is essentially
off and should be brought back on-line and checked
out before Ready state is entered.
Transition from Propel State to Ready State: This
transition will occur if all of the following conditions
exist:
• The accelerator pedal is not pressed.
• The retard pedal or lever is not pressed or is
pressed such that an insignificant amount of
retarding effort is requested.
• Truck speed is less than the motor overspeed
limit.
• At least one of the following conditions is true:
a. Retard speed control is not selected.
b. Truck speed is below the set retard speed,
and acceleration is such that no retard effort
is (currently) required to maintain this
condition.
Transition from Propel State to Retard State: This
transition will occur if at least one of the following
conditions exists:
• Truck speed is such that retard is allowed, and
the retard pedal or lever is pressed such that a
significant amount of retarding effort is
requested.
• Truck speed exceeds the motor speed limit.
Overspeed will not be engaged such that it
prevents the truck from propelling at 40 mph (64
kph).
• All of the following conditions are true:
a. Retard speed control is selected.
b. Truck speed exceeds the set retard speed,
or the truck is accelerating such that the
truck speed will soon exceed the set retard
speed if no action is taken.
c. The truck is configured such that accelerator
pedal signal does not override the retard
speed control.
Transition from Retard State to Ready State: This
transition will occur if all of the following conditions
exist:
• Overspeed is not active.
• At least one of the following conditions is true:
a. The retard pedal or lever is not pressed or is
pressed such that an insignificant amount of
retarding effort is requested.
b. Truck speed is such that retarding is not
allowed.
• At least one of the following conditions is true:
a. Retard speed control is not selected.
b. Truck speed is low enough such that retard
speed control is not active.
c. The accelerator pedal is pressed, and the
truck is configured such that the accelerator
pedal overrides the retard speed control.
This allows the configuration constant to
determine if pressing on the accelerator
pedal kicks the truck out of retard, even if the
retard speed control is still active.
• The retard torque control logic exit sequence is
complete.