Valtra 6000 Workshop Manual page 426

35. Autocontrol IV
Valmet Autocontrol IV Tractor Control System is standard equipment on tractors 6600E --- 8750E from the beginning of the year
1994 (662343---). Autocontrol IV replaces Autocontrol III which is shown in section 34.
Autocontrol IV is in many points the same as Autocontrol III. The main difference is that Autocontrol IV controls the 3---step Delta
Powershift gear (Autocontrol III controlled the 2---step quick ---shift gear).
Manual or automatic control with aid of the 3---position rocking switch.
Rear edge depressed: 4WD disengaged except when latched together brake pedals are depressed.
Front edge depressed: AC IV controls automatically the 4WD as follows:
4WD engages
--- when the rotation speed difference of the front
and rear axle exceeds 9%
--- when braking with latched together brake
pedals (also in manual position).
--- when the engine is stopped
Manual or automatic control with aid of the 3---position rocking switch.
Middle position: lock is engaged manually but disengages when brake pedal/pedals are depressed
Front edge depressed: AC IV controls automatically the lock as follows:
Diff. lock engages
--- when one rear wheel rotates 20% faster than the
other and the driving speed is less than 12 km/h
Manual or automatic control with aid of the 2---position rocking switch.
Rear edge depressed: the gear is controlled with the push buttons in the gear lever knob
Front edge depressed: AC IV controls the gear automatically as follows:
Change down
--- changes automatically down when the loading
increases
--- changes to the lowest ratio when the tractor
speed is below 1,5 km/h and the clutch pedal is
depressed.
Note! In the automatic position the gear ratio can temporarily be changed with the push buttons.
There is a buzzer in the instrument panel which alarms when the engine is stopped and the parking
brake is not applied.
4WD control AC I V
Middle position:4WD is engaged manually
Differential lock control AC I V
Rear edge depressed:differential lock is disengaged.
Delta Powershift control AC I V
1. 1. 1994
6600E
1. 1. 1995 8100E-- 8750E
4WD disengages
--- when the engine is started (in automatic (A)
position)
--- when the wheel slip is less than 2% for more
than 6 seconds.
Diff. lock disengages
--- when the rear wheel slip is less than 10 % during
a period of one second (speed <12 km/h).
--- when the brake pedal/pedals are depressed
(also in the manual position)
--- when the clutch pedal is depressed
--- when the steering angle is more than ± 15 ˚
--- when the tractor driving speed is over 12 km/h
--- when the tractor is stopped
Change up
AC IV selects automatically the best possible hig-
her ratio
--- highest ratio reduces noice and fuel consump-
tion.
385
Model Code Page
350 1