TeeJet LH 1200S - Manual (Page 18)

LH 1200S O PERATORS MANUAL
18 LH A GRO
ENCODING
FORWARD SPEED CALIBRATION (WHEEL CIRCUMFERENCE)
Key Function
WHEEL CIRCUMFERENCE
The distance in centimetres that is driven per pulse from the speed sensor is
encoded here.
Depending on which vehicle is used the speed signal can come from a sensor built
into the gearbox, from a sensor fitted by the prop. Shaft (4-wheel drive) or from a
sensor fitted by one of the wheels.
The LH 1200S features an automatic speed calibration procedure, which can be
used for integrated or prop. Shaft sensors. The automatic calibration procedure
can also be used for normal wheel sensors if the wheel circumference does not
exceed 100 cm when divided by the number of magnets.
NOTE! It is recommended to fit as many magnets on the wheel as necessary to
ensure that the encoded wheel circumference does not exceed 100 cm.
AUTOMATIC SPEED SENSOR CALIBRATION
1. Measure a distance of 100 m and drive to the start mark.
2. Press the “WHEEL CIRCUMFERENCE” key once. Release the key and then
press and hold the key down until “AUTO” is displayed. Press the “WHEEL
CIRCUMFERENCE” key again and the monitor is ready for automatic speed
sensor calibration.
3. Drive the 100-metre stretch and stop exactly at the stop mark. The monitor will
count the number of pulses received from the sensor.
4. If the monitor has received enough pulses from the sensor (over 100 pulses
per 100 metres), it will calculate the effective wheel circumference when the
“WHEEL CIRCUMFERENCE” key is pressed again. The calculated value is
shown on the display.
If the monitor has not received over 100 pulses over the 100-metre stretch, it will
display 0 after pressing the key. One of the following two methods can be used
hereafter:
a: Manual measuring of the value to be encoded as described below
b: Fitting more magnets to increase the number of pulses per 100 metres.
REMEMBER!
It is important that the distance between the magnets is the
same. Otherwise, the displayed speed will fluctuate.