RetroSign GR1 & GR3 · Retroreflectometer
9
Calibration
RetroSign features two levels of calibration:
Quick
and
Full
.
Quick
calibration is an “everyday” calibration using zero results and reference values from the latest full calibration. This
option may only be used with the same reference unit that was used for the full calibration.
Full
calibration is used for high accuracy calibration of zero and reference.
Quick calibration
Quick calibration is initiated by pressing the button and then the trigger. Mount the reference cap (reflective side)
before triggering. The display shows
WAIT
and the Calibration is executed immediately using previous defined refer-
ence values. If the calibration fails, the display shows a short warning message saying that the old calibration values
will be used; a status flag will be set and logged for this condition.
Full calibration
Full calibration is initiated by pressing the
button and then. Follow the displayed procedure.
Zero
Mount the zero cap (dark side) on the instrument. Press the or the trigger when ready. The display shows
WAIT
while measuring and then shortly displays the measured zero values. If the measured values are ok the instrument is
ready for the next step in the calibration procedure. If high zero values are measured, a warning text will be shown and
the user asked to check the black target and try again.
Reference
Mount the reference cap (reflective side). If necessary edit the displayed reference value using or until it
matches the value printed on the reference unit, press or the trigger to advance to the next reference value. When
all reference values has been checked and edited the instrument executes the calibration process.
WAIT
is displayed
during the actual calibration measurement and then the calculated calibration factors are shortly displayed. If errors are
detected during the calibration process a warning text is displayed and the user is asked to check the white target and
retry the calibration by pressing or the trigger again. The reference values will not need to be checked again.
When the calibration is successful, continue by pressing , or the trigger.
After a successful calibration the icon is shown and the instrument is ready for measurements. It is good practice
to do a measurement on the calibration unit immediately after the calibration to check the values.
Reduced aperture option
When the instrument is configured for measurements with reduced aperture the calibration monitor should be disabled.
This changes the checking of the calculated calibration values and displays the icon to alert the user that this op-
tion has been selected.
The instrument must be recalibrated whenever this function is enabled or disabled
.
See also paragraph
Aperture Reduction
in this section for further information.
