ASTECH LDM41A - DT - Distance Tracking; DS - Distance Tracking (<7 M); DW - Distance Tracking with Target Board (10 Hz)

Commands and Parameter LDM41A and LDM42A Manual
Page 28 ASTECH GmbH
8.2 DT – distance tracking
Input parameter SA, SD, SE, SF, ST, OF
Output RS232/RS422, digital switching output, analog output
DT mode can be chosen for distance measurement of different kinds of
surfaces (varying reflectance). In this type of distance tracking mode, the
LDM41A and LDM42A uses internal algorithms to continuously evaluate the
quality of the Laser radiation signal that is coming back. This may cause longer
measuring times in the case of poor reflectance or sudden jumps in distance.
The minimum time to measure is 240 ms, the maximum time is 6 s. If the
measuring signal fails to reach a specified quality within six seconds, an error
message is output.
The time to measure may also be limited by setting the ST parameter to a
desired value. ESC stops the measurement.
8.3 DS – distance tracking (<7 m)
Input parameter SA, SD, SE, SF, ST, OF
Output RS232/RS422, digital switching output, analog output
Operation in DS mode makes sense where different types of surfaces have to
be measured at close range up to 7 m. Compared to DT measuring mode, it
allows a higher measurement rate. Within the range from 0.1 m to 0.5 m,
measuring accuracy is restricted (± 4 mm). Measuring time (time to measure)
can be limited via ST parameter settings.
ESC stops the measurement.
8.4 DW – distance tracking with target board (10 Hz)
Input parameter SA, SD, SE, SF, OF
Output RS232/RS422, digital switching output, analog output
DW mode performs at a steady measuring rate of 10 Hz. As a necessary
precondition for measured values to be stable, a white target board must be
placed at the selected object. There must be no sudden jumps in distance
greater than 16 cm within the measuring field! ESC stops the measurement.