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Bosch Rexroth Canada ı 03.10.2011 ı Revision 5.4
4 Ground Speed Configuration
4.1 Overview
The CS-440RC Controller determines ground speed by monitoring the pulses it
receives from the ground speed sensor mounted in the vehicle transmission. This
sensor is the same sensor providing the vehicle’s odometer with the necessary input
for the odometer to have the ability to indicate speed and distance.
In order for the CS-440RC to have the ability to calculate ground speed and distance
it must first be accurately calibrated. The process of calibration tells the CS-440RC
exactly how many pulses per KM or Mile it will receive from the transmission
mounted sensor.
The process of calibration needs to be completed for each vehicle, as each vehicle’s
system is not exactly the same. Discrepancies may occur due to sensor mounting
differences, tire sizes differences etc.; thus, calibrating each vehicle independently
is the only way of ensuring accuracy.
There are a number of methods for calibrating the ground speed input and each
method may result in varying levels of accuracy. Listed below are the most common
techniques which may be used, the accuracy level for each technique is reflected in
the numbering with number one (1) being the most accurate.
1.
Driving the vehicle over a measured distance. By measuring out the distance of
one (1) KM for metric system users or one (1) Mile for Imperial system users and
driving the vehicle over this measured distance allows the CS-440RC to count
the pulses it receives over this distance. This pulse count can then be entered
into the “Pulses per KM/Mile screen and once this value has been entered the
CS-440RC ground speed is properly calibrated.
2.
Auto-calibration to a hand held GPS unit. By driving the vehicle at a
predetermined speed using a handheld GPS unit as the speed indicator. Using a
hand held GPS unit will result in greater accuracy then using the vehicle
speedometer. The accuracy level is only as accurate as the GPS Unit’s
calibration. During the calibration process the CS-440RC will determine the
pulses per KM or Mile; this count will be reflected on the “Speed input” screen
once the auto calibration process has been completed.
3.
If the vehicle is equipped with a GPS system, auto-calibration to the GPS
provider’s ground speed signal. By driving the vehicle at a predetermined speed
using the GPS provider’s ground speed signal as the speed indicator. The
accuracy level is only as accurate as the GPS system’s calibration. During the
