horsch Leeb 5.280 VL, Operating Instructions Manual

Page: 281 / 308

Calibrating the flow meter
The flow meter is calibrated by using the tank
method. A major amount of water is thereby
discharged from the spraying mixture container
over a certain period of time.
With the help of simulated travel speed and the
spraying duration the distance the machine will
travel can be calculated.
Distance = travel speed x spraying duration
Multiplied with the working width gives you the
area that would be processed when working with
the simulated travel speed and spraying time.
Processed area = distance x working width
You can then calculate the required amount of
spraying mixture and compare it with the amount
actually used.
Required placing quantity =
processed area x placing quantity
The correction factor for the set pulses/26 gal
lqd is thereby determined. This is the required
quantity, divided by the quantity actually placed.
required quantity
placed quantity
Correction factor =
¾
The value is finally corrected under parameter
Main flow pulses
, and a new calibration is made
by using the new values.
For the crop protection sprayer the standard
value is 2,100 pulses/26 gal lqd.
Example:
The numerical values in the example were
randomly chosen and may differ from practice.
•
Machine with 120 ft working width.
•
Setting on terminal: 2,100 pulses/26 gal lqd
¾
Set 21 gal lqd/ac as placing quantity.
¾
Set 6.2 mph as simulated travel speed.
¾
Note the filling level spraying mixture con -
tainer.
¾
Read the value under parameter Pulses main
flow (pulses/26 gal lqd) in the terminal and
write it down.
¾
Switch on the crop protection sprayer and run
it for 15 minutes.
The distance thereby is:
6.2 mph x 0.25 h = 1.55 mi = approx. 8200 ft
Multiplying this with the working width gives you
a processed area of:
8200 ft x 120 ft = 984.000 ft² = 22.5 ac
The product of this area and the set placing
quantity results in the required amount of spray-
ing mixture:
22.5 ac x 21 gal lqd/ac = 473 gal lqd
This value is now set into relation to the quantity
actually placed. The actually placed quantity is
the difference in filling level spraying mixture
container before and after calibration.
Here the quantity actually placed is: 488 gal lqd
The correction factor in this case is:
473 gal lqd
488 gal lqd
Correction factor = = 0.97
The placed quantity is too high, the value under
parameter 457 therefore needs to be corrected.
New value (pulses/26 gal lqd):
2,100 x 0.973 = 2,043
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