NDC BETA LaserMike LaserSpeed Pro 8500-4, Instruction Handbook Manual

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LaserSpeed Pro 8500-4 Instruction Handbook: Interfacing with the LS8500-4 4-11
The Graph above shows the delay in the speed measurement caused by the smoothing algorithm. The delay
causes the average speed to lag during acceleration and lead on deceleration. The average speed is fed to
the pulse generator to generate the pulse output. Therefore, obtaining length by counting the pulses will give
a length error according to the following formula:
L
err
=( Starting Speed
– Ending Speed
) x ½ DIP Average
If the Length measurement is used to obtain length for a line the starts and ends at zero speed then there is
no Length error cause by the smoothing algorithm. If the Length measurement use for cutting or marking of
short lengths during and acceleration or deceleration periods then there will be a length error during the ac-
celeration and deceleration of the line. The error can be calculated according the formula above.
To minimize the length error caused by the smoothing algorithm, select a smaller DIP averaging time in the
Configuration tab of the LaserTrak Software. The configuration Standard Tab has three selections for the
Us-
er Update Rate . If you select one of these settings the software will automatically select the best DIP averag-
ing time. The three selections are; Fast, Medium and Slow. For operation that needs to calculate the length
during the acceleration or deceleration select Fast for the User Update rate. The default setting is Medium
and this selection should be used for most applications. For production lines that move very slowly, use the
Slow selection.