Komatsu 830E-AC Shop Manual page 980

The "short term" numbers listed on the chart indicate
the combination of speeds and grades which the
vehicle can safely negotiate for a short duration
before system components reach the maximum
allowable temperature during retarding. These
speeds are faster than the "continuous" values,
reflecting the thermal capacity of various system
components. System components can accept heat-
ing at a higher-than-continuous rate for a short period
of time. Beyond this short duration of time, the sys-
tem would become overheated.
If the vehicle is operated at "short term" grade and
speed limits for a period of time exceeding thermal
capacity, the Propulsion System Controller (PSC)
gradually reduces retarding effort from "short term" to
"continuous". The "retard @ continuous" indicator
light will illuminate alerting the operator of the retard-
ing reduction and the need for a reduction in speed.
The operator must use the service brakes to quickly
slow the truck to maximum "continuous" retarding
limits or less.
Do not LIGHTLY apply the service brakes when
attempting to slow the truck on a downhill grade.
Overheating of the brakes will result. FULLY
apply the brakes (within safe limits for road con-
ditions) in order to quickly slow the truck to max-
imum "continuous" retarding limits or less.
NOTE: The "three minute" curve is a MINIMUM; the
actual time limit could
temperature, barometric pressure and recent motor
power levels can affect this number.
N5-8
be greater. Ambient
Operator Controls
The "short term" rating will successfully accommo-
date most downhill loaded hauls. It is necessary to
divide haul road grade segment length by allowable
speed to determine actual time on grade. If actual
time on the grade exceeds the allowable limits, the
grade will need to be negotiated at the "continuous"
speed.
The "continuous" numbers on the chart indicate the
combination of speeds and grades which the vehicle
can safely negotiate for unlimited time or distance
during retarding.
DO NOT exceed these recommended MAXIMUM
speeds when descending grades with a loaded truck.
10/06 N05070