Smithco Spray Star 1607P (1999) Operator Manual - Manual (Page 22)

20
Operation
PROGRAMMING THE 844 SPRAYER CONTROL SYSTEM
(
CONTINUED
)
SPEED SENSOR TYPE
Default = 250
Speed Calibration = 621
During Speed Calibration, the 844 will automatically sense whether a Wheel
Sensor or Radar Speed Sensor is being used.
While in the Speed Calibration Programming Step, the symbol will be flashing at the top of the display. The
programmable value (250) will be displayed in the lower right corner of the display.
MAGNETIC PULSES
The speed sensor needs to be calibrated in order to provide the proper speed and area readings. The value for
this step is the number of pulses generated by the speed sensor in 300 feet. This value can be determined by
automatic calibration while driving exactly 300 feet, or by entering the number manually.
Automatic Calibration:
To automatically calibrate the speed sensor, mark off a distance of exactly 300 feet. While still in the speed
calibration program step, position your sprayer at the beginning of your 300 foot 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, CRL 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 ex-
actly 300 feet and press the key to validate the number in the display. The speed sensor is now properly
calibrated.
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, depress the key twice.
During the automatic calibration step, the 844 automatically senses whether a magnetic sensor or 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 on full revolution. Then use the following formula:
3600 x{# magnets on wheels (usually 2)}
i.e.
3600 x 2
= 240
Wheel Circumference in inches 30
The result can be entered as a 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.