Fast 973P Series, Руководство оператора

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4.7.4 MACHINE YARD CALIBRATION
After the nozzles have been calibrated, it is recom-
mended that the entire system be calibrated. A yard
run is the simplest method to determine total volume
delivered. To calibrate in the yard, follow this proce-
dure:
1. Fill the tank full of water (no chemicals).
2. Check that all screens are clean.
3. Set the chemical system and boom pressure
to the desired value and run the tractor at the
selected engine RPM.
4. Spray in a stationary position for a known period
of time.
5. Refi ll the tank and measure accurately the
amount of water used.
6. This will give the amount of spray used per time.
The total volume can be changed by increasing or
decreasing the chemical system pressure. However if
a change is made, it is recommended that the entire
system be calibrated again to determine the new
volumes.
4.7.5 GROUND SPEED CALIBRATION
For optimum spraying results, it is important to main-
tain a known constant speed to spray the required
chemical over a given area. Because of wheel slip-
page, the operator cannot rely on the tractor speed-
ometer reading to give the value of true ground
speed. The unit must be timed over a known dis-
tance to determine true ground speed. To calibrate,
follow this procedure:
1. Mark off distance of 100, 200 or 300 feet in the
fi eld to be sprayed (longer distances provide
greater accuracy).
2. Place the tractor in the gear to give a speed
between 6 and 8 mph (9.5 and 13 kph) and at the
selected engine RPM.
3. With the tank 1/2 full of water, drive the tractor
and sprayer through the measured distance.
4. Record the time required to travel the measured
distance.
5. From Table 3 determine the actual tractor speed.
You can shift gears to change speed but it is rec-
ommended that you go through the measured
distances again to determine true ground speed
when using the manual controller.
6. If the machine is equipped with the automatic
controller, the ground speed can be changed
by up to 20% without acquiring adjustments.
However, do not decrease the throttle below its
2/3 setting.
IMPORTANT
Always operate at the engine RPM
determined in Section 4.9.1.