schmersal PSC1-C-10 Series, Руководство по установке

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Installation manual
PSC1-C-10 Installation manual V2.6 Page 57 of 173
Version: 57E
4.2.2.5 Safety-related shutdown thresholds, encoder systems for position and speed
acquisition
As a basic measure, plausibility tests between the two measurement channels A and B for speed and
position on the PSC1 module are undertaken with the actual values for position and speed and tested
against configured thresholds.
The
incremental shutdown threshold describes the position deviation that can be tolerated between
the two acquisition channels A and B in the measurement section unit.
The
speed shutdown threshold describes the speed deviation that can be tolerated between the two
acquisition channels A and B.
Diagnostic functions are available in the SCOPE dialogue box in the parameter configuration tool to
determine the optimal parameter values for the application.
Note:
Speed and acceleration are acquired values with a minimum digital resolution.
This situation limits the smallest possible speed or acceleration that can be acquired and defines the
digital step size for the input values.
Speed resolution:
The speed is acquired down to a frequency of 500 Hz or
500 steps/s using the frequency measurement method, below that using a time measurement
method. This situation produces the curve shown below for the acquisition error:
Acceleration resolution
The digital resolution of the acceleration is limited by the maximum gate time of 256 ms and the
resolution of the encoders. The graph below shows the lowest acceleration that can be measured as a
function of the resolution in rev/min, mm/s² and m/s².