Terex TA400, Руководство по эксплуатации

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Controls and Operating
3-28
Transmission Retarder
This switch (1) is used to request the transmission retarder. The retarder
will engage when the switch is pressed, and provided that the
transmission 'Stop' warning light is 'OUT', the transmission is in 'lockup',
the transmission oil temperature is within operating range and with
reference to the retarder switch operation mentioned in Section 3. The
retarder lever (2) is then used to determine the level of retardation
required. It is a six stage retarder that is at its maximum when the retarder
lever is in its downmost position.
The retarder is used to apply a continuous braking force to hold the truck
to a safe steady speed when descending gradients, to reduce the need
for service brake applications, thus reducing service brake wear and
preventing overheating. The retarder may be used any time to slow down.
If additional braking is required, apply the service brakes. The retarder is
not intended for bringing the machine to a halt, or for sudden deceleration
- the service brakes should be employed for this purpose.
Retarder Operation
Before the machine starts down the gradient, select the retarder. Refer to
Section 3 for conditions applicable for the retarder to be active. For maxi-
mum retardation, oil circulation and cooling, the machine downgrade
speed (retarder applied) gear range should be manually selected and
should be high enough to keep the engine operating at governed speed.
Generally the gear used to ascend a grade fully laden is also correct for
its descent. If the rate of descent is too fast, the engine brake should be
applied which will allow a safe descent and efficient retarder operation. If
further braking is required still, apply the service brakes.
For recommended downgrade speed gear selection, please refer to the
gradeability chart.
Frequent use of the retarder will result in higher transmission oil
temperatures. Therefore, the oil temperature gauge should be checked
frequently. During normal operation the gauge should read in the green
sector. However, during converter mode, and during retarder operation,
temperatures may reach the yellow sector.
NOTICE:
Retarder function at elevated retarder temperatures
The speed must be reduced by using the service brakes so that the
oil is cooled down. Reduce downgrade travel speed to avoid the oil
overheating and possible damage to the transmission.
1
HI
LO
MOT00335
2
HI
LO
MOT00308
182 ˚C (360 ˚F)
166 ˚C (330 ˚F)
149 ˚C (300 ˚F)
143 ˚C (290 ˚F)
Maximum retarder capacity
reduction
Retarder capacity
reduction begins.
Retarder Overtemp light is
activated.
An active Diagnostic Code
P2740 is logged.
Preselect Downshift
schedule is invoked.
Capacity Reduction continues until it is reduced to
approximately 27% of maximum available capacity.