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844E Sprayer Control
Automatic Calibration
To automatically calibrate the speed sensor, mark off a distance of exactly 300 ft / 100 m. While still in the speed
calibration program step, position your sprayer at the beginning of your 300 ft / 100 m course and press the
and
keys simultaneously to clear the contents of the display and to activate the auto calibration mode. When
the auto calibration mode has been activated, CAL will be displayed at the lower right of the display. Next, press
the
key once to begin the calibration process. Now drive the course and the 844 will count the pulses as the
sprayer moves. The speed at which you drive over the course is not important. Stop the sprayer at exactly
300 ft / 100 m and press the
key to validate the number in the display.
The speed sensor is now properly calibrated.
NOTE: Once the auto calibration mode has been activated, no other functions of the 844 are possible until the
console receives speed impulses for calibration. To deactivate the auto calibration mode, press the key
twice.
During the automatic calibration step, the 844 automatically senses if a radar ground speed sensor is installed. If
you prefer to enter the speed value manually, refer to the following instructions.
Manual Calculation:
To manually calculate the proper value for Wheel Speed Sensor pulses, you need to know the circumference of
the wheel to which the sensor is mounted. It can be measured by marking the tire and measuring the distance
covered as that mark makes one full revolution.
Then use the following formula:
The result can be entered as an alternative to using the automatic calibration method. Use the
or
keys to
adjust the value. Press the
key to validate the value and advance to the next programming step.
