Hitachi ZW180 Technical Manual page 68

Forward/Reverse Selector Control while Traveling
Purpose: To protect the transmission by preventing
forward/reverse selector unless the vehicle
speed is lowered than the set speed when
traveling over the set speed.
Operation:
1. In case the FNR lever is turned to reverse while
traveling forward speed is higher than the allow-
able speed of FNR clutch selection, MC reduces
the vehicle speed shift by sending the speed shift
signal in order from 4→3→2 if the speed was set
in speed 4.
2. If the vehicle speed is lowered to the set speed by
operation of the brake pedal, MC transmits the
signal to the reverse clutch solenoid valve and
tarns the clutch into reverse.
3. When the vehicle speed increases while the ac-
celerator pedal is depressed, MC shifts up by
sending the speed shift signal from speed 2 to
speed 3 to each speed shift solenoid valve.
NOTE: In case the FNR lever is operated when the
vehicle speed is below the allowable speed
of FNR clutch selection, the FNR clutch is
operated regardless of the speed shift.
NOTE: The shift switch has two switches, and the
combination of their ON varies depending
on each speed shift. The controller judges
which speed shift has been selected by the
combination of the two input signals.
NOTE: The FNR switch does not transmit the neu-
tral signal. In case of no electric current
from the FNR switch, the controller judges
that the switch is neutral (N).
SYSTEM / Control System
T2-1-26