VB20SL User Guide
Page 9 of 30
Using the VB20SL with one GPS antenna
The VB20SL can be used like a traditional VBOX. Only Antenna A is needed if the VB20SL is to be used like a traditional VBOX without the requirement to
measure Slip, Pitch, YAW rate and Lateral Acceleration channels.
For single antenna use (for standard, non-slip GPS data), the antenna should be connected to the Ant A connector.
Velocity can be output on either the Analogue or Digital outputs.
The VB20SL has a brake trigger input so not only can the VB20SL measure and output Velocity it can measure and output Trigger Velocity, Trigger to zero
Time and Trigger to zero Distance. This data is logged to SD card and available on the CAN bus or USB/serial connection bus along with all the other GPS
data.
NOTE: When measuring a braking distance the GPS optimisation must be set to High, via the Front Panel controls. And
the Velocity Kalman filter set to 0 (zero).
Display Screen
The Display screen will display data when operating it also displays all the menus required to configure the VB20SL via
the front panel controls.
On start-
up, the display screen shows the unit’s firmware version and current offset value.
During normal operation, the display screen displays Speed (mph or km/h) and Slip Angle, as well as the number of
satellites that the VB20SL has locked on to. There are also three status displays.
OK (Green):
Indicates that the VB20SL has sufficient satellites locked to allow normal operation.
RTK (Orange):
This flashes to indicate that the VB20SL has locked onto sufficient satellites for single antenna (Speed sensor only) use. The unit will be able to give accurate
data for all channels except Slip Angle, Pitch Angle, True Heading, Lateral Velocity and Yaw Rate.
WAAS/40CM (Orange):
Indicates the DGPS solution that is currently being utilised by the Slip Angle sensor.
SATS (Yellow):
This flashes to indicate that the VB20SL has insufficient satellites and will not be able to operate at all.
Logged File name:
When an SD card is inserted the file name of the logged file appears on the screen whilst data is being logged.
