Speed sensor factor, Autocal – Great Plains V-300F Operator Manual User Manual
Page 54
50
V300 & V300F
Great Plains Manufacturing, Inc.
148-057M-A
11/15/2007
Speed Sensor Factor
The forward speed sensor is magnetically operated and
senses the main drive shaft rotation. In order to display
the correct speed and accumulate area correctly, the
instrument must be programmed with the correct Speed
Sensor Factor (SSF). This is the distance traveled
between two signal pulses received from the sensor.
The S.S.F. entered can be entered from calculated val-
ues, or the instrument can automatically calculate it via
the “Autocal” function. The Autocal function is more
accurate, as it accounts for drill configuration, field condi-
tions, tire slippage and the effective rolling radius of the
actual tires in the present conditions.
Autocal
For maximum accuracy, perform an auto-calibration in
field conditions.
Note: The drill must be hitched for this operation, and
must be lowered to field position. Perform this cali-
bration before loading seed and fertilizer. If materi-
als are already loaded, disconnect clutches and/or
chains or set meter rates to zero to avoid unintend-
ed planting.
1.
Set two markers at 100 meters (328 feet) apart.
Choose a convenient reference point on the tractor/
implement, that is visible to the tractor operator, and
position this point opposite the first marker.
2.
Channel Select
to Forward Speed
.
3.
Press and hold the
button. The units of measure
display (see page 47) appears for a few seconds.
Continue holding the button until a numeric display
appears.
While continuing to hold
, press
.
The display flashes “AUtO” indicating that it is ready
for calibration. Release all buttons.
5.
Drive the vehicle until the chosen reference point on
the tractor/implement is opposite the second marker.
The instrument counts and displays the sensor
pulses received over the distance traveled.
6.
Press the
button to complete the Autocal rou-
tine. The calibration factor is automatically calculated
and stored in memory.
Figure 50
Ready for Autocal
22632