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4.3 Commands and their functions
Command entries are not case-sensitive. This means that small and capital lettering can be used for
commands.
Any command which is to be sent to the LLD must be terminated by a hexadecimal 0Dh (carriage return)
character.
Where decimal digits are to be entered, they must be separated by period (2Eh).
For command parameter entries, one must distinguish between parameter settings and parameter queries.
Querying is achieved with a command in simple format. e.g. (for alarm centre parameters):
AC[Enter]
For parameter setting, a new value must be added after the command with no delimitation sign in between, for
example:
AC20.8[Enter]
In the given example, the alarm centre will be set to 20.8.
4.3.1 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). Working
in this mode, the LLD uses internal algorithms to continuously evaluate the quality of laser radiation that is
received back. This may cause longer measuring times in the case of varying reflectance or sudden jumps in
distance. The minimum time to measure is 160 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.
4.3.2 DS…distance tracking 7 m
Input parameter
SA, SD, SE, SF, ST, OF
Output
RS232 / RS422, digital switching output, analog output
Mode
DS
can be used for measurements on different reflecting surfaces for distances between 0,1…7 m. In
comparison with mode DT the measurement frequency is higher in mode DS. Measuring time will be set with
parameter ST.
Calculation of measuring time:
Mode DS
measuring time
≈
ST x 150 ms (except for ST = 0)
Mode DT
measuring time
≈
ST x 240 ms (except for ST = 0)
4.3.3 DW…Distance tracking with cooperative target (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!
