Zetor FORTERRA HSX 120 Operator's Manual page 68

The values 1600 and 1900 engine revolutions necessary for automatic multiplier shifting used in this example are purely
informative, in practice the number of revolutions is set by the driver according to the specific use of tractor.
With multiplier pre-selection on, it is possible to shift the multiplier gears also manually on a gear shifting lever, but only within the
range of set values (engine revolutions); i.e. in the example presented in the range of revolutions from 1600 to 1900 rpm, when
reaching the saved revolutions for automatic shift of multiplier gear the multiplier is automatically shifted without driver´s interven-
tion.
In this case (multiplier pre-selection switch on), manual shifting of multiplier by buttons on gear shifting lever does not influence
the values (engine revolutions) that are saved in the system of automatic multiplier shifting.
After turning the multiplier pre-selection on the dashboard off (the control on the switch is not lit) it is possible to shift the torque
multiplier gears only manually by buttons on gear shifting lever.
Beware!
With tractor travel, when the pre-selection multiplier switch on the dashboard is off, the system of automatic multiplier se-
lection keeps on reading the values (engine revolutions) with every use of H or L buttons use on gear shifting lever. After
switching the multiplier pre-selection switch, the system of automatic multiplier shifting uses the last read value (engine
revolutions) i.e. values read with last usage of H and L buttons on the gear shifting lever with multiplier pre-selection off
DRIVING OPERATION
Example of use:
We are driving with a tractor with multiplier pre-selection off with multiplier shifted to M
gear, with engine revolutions of 1600 rpm we press L button on the gear shifting lever,
by this we shift the torque multiplier to L gear, now we increase the engine revolutions
to 1900 rpm and we press H button on the gear shifting lever, by this we shift the
torque multiplier back to M gear. We continue driving with the tractor. Now we turn on
the multiplier pre-selection switch on the dashboard. From this time, the automatic
multiplier gear shifting system shifts gears of torque multiplier without any intervention
of the driver in the following way:
a - With the drop of engine revolutions under 1600 rpm automatically shifts the
multiplier to lower gear (lowering travel speed)
b - When increasing the engine revolutions above 1900 rpm, the multiplier
automatically shifts to a higher gear (increasing the travel speed)
FH12N0586
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