Override Switch; Retard Speed Control (Rsc) Switch; Retard Speed Control (Rsc) Dial - Komatsu 730E Operation & Maintenance Manual

OM3241
Operator Cab and Controls

Override Switch

Override switch
(7, Figure 32-6)
is spring-loaded
to the OFF posi-
tion. When
pushed inward
and held, this switch has several uses.
1. The override switch permits the operator to
move the truck forward when the selector
switch is in FORWARD, the dump body is
raised, and the brakes are released.
Only use the override switch in emergency situa-
tions.
2. If the operator stops the truck on an uphill
incline, the override switch can be used to set
up the forward propulsion while the brakes are
applied. As soon as the forward propulsion is
felt, release the brakes. As the truck begins to
move forward, release the override switch.
3. The override switch deactivates the retard
pedal function when the speed of the truck is
below 5 kph (3 mph).
4. The override switch is also used to reset an elec-
tric system fault when indicated by the red warn-
ing light. Refer to Overhead Warning/Status
Indicator Light Panel in this section.

Retard Speed Control (RSC) Switch

Retard speed control
switch (6, Figure 32-6)
turns the system off or
on. Push the knob in
to turn the system off,
and pull the knob out
to turn the system on.
.

Retard Speed Control (RSC) Dial

RSC dial (5, Figure 32-6) allows the operator to vary
the downhill truck speed that the retard speed control
system will maintain when descending a grade.
When the dial is rotated counterclockwise
toward the turtle symbol, the truck will
descend a grade at lower speeds.
When the dial is rotated clockwise toward
the rabbit symbol, the truck speed will
increase.
The throttle pedal position will override the RSC set-
ting. If the operator depresses the throttle pedal to
increase the truck speed, dynamic retarding will not
activate unless the truck overspeed setting is
reached, or the retard pedal is used. When the throt-
tle pedal is released, dynamic retarding will activate
at the RSC preset speed. The RSC control will main-
tain the truck speed at the preset limit.
To adjust the RSC control, pull switch (11) to the ON
position. Start with dial (12) rotated toward the fastest
speed while driving the truck at the desired maximum
speed. Relax the throttle pedal to let the truck coast,
and turn the RSC dial slowly counterclockwise until
dynamic retarding is activated. Dynamic retarding will
now be activated automatically anytime the set
speed is reached, the RSC switch is ON, and the
throttle pedal is released.
Operation - Section 32
Page 32-7
IN OFF
OUT
ON