VRT Hydraulic Drive
– Calibration
Page 77
05/06
the tractor before re-
engaging the fan’s
flow control valve.
17.
Start the fan by engaging the tractor’s
hydraulic system. Adjust the fan speed
at the tractor if equipped with closed
centre hydraulics or at the seeder’s flow
control valve if open centre hydraulics.
For information on appropriate fan
speeds refer to the Blower Operation
section in this manual (page 118 ).
18. To begin seeding operation simply push
the RUN/HOLD key. The monitor should
come off hold and the appropriate rates
of application should be displayed.
Refer to the Monitor Operation (VRT)
section, page 64, for more detail.
NOTE: After completing the calibration
procedure it is recommended to record the
various values on the record sheet provided
(page 89-90) for future reference.
NOTE: Some fertilisers run more
freely than others and actual usage
may vary from the first calibration
sample taken. It is recommended that the
operator checks the actual usage after the
first bin load. It may be necessary to
perform a second calibration test after
some material has been metered.
Changing Drive Sprocket Ratio
The VRT hydraulic drive metering
system is capable of metering products at
very low rates (eg. 3kg/ha of canola)
through to extremely high rates (200kg/ha
and greater of fertiliser).
The hydraulic motors that rotate the
metershafts have a limited
speed range. To
increase their range of operation a simple
quick-change sprocket ratio system has
been fitted to the right hand side of the VRT
equipped meterbox.
To change the sprocket ratio simply
undo the 2 x M8 screws, using the butterfly
handle supplied, and remove the retaining
collars. Now, simultaneously pull the 2
sprockets off the shafts leaving the chain
attached.
Fig. VC9 Removing the retaining collars.
Reverse the placement of the sprockets
to obtain the desired ratio (refer decal on
underside of meterbox cover). You may need
to rotate the metershaft slightly until the
second sprocket lines up with the keyway on
the agitator shaft. When both keyways line
up you can then push the sprockets onto the
shaft together. If you experience any problem
with the alignment, remove the chain and
place one sprocket on at a time.
Fig. VC10 Sprocket removal.
NOTE: It is important to disengage
the tractor’s hydraulic system and to
TURN THE TRACTOR OFF
before
attempting to work on or around the metering
system. The metering system could be
activated if someone pushes the prime key
or calibration function from the monitor.
