ETAS ES930.1 - Definitions; Maximum Input and Common Mode Voltages; Compensation of Group Runtime

ETAS Analog Input Channels ("AI 1-4"/"AI 5-8" Connections)
ES930.1 - User Guide 47
6.3 Compensation of Group Runtime
The group runtime is the time required by the Input signal of an analog or digital
filter to pass through the filter.
One property of the ES930.1 is the in-module compensation of the group run-
time. For this purpose, the group runtimes of the analog anti-aliasing filter and
the configurable digital filter are taken into account. A time shift of the signal in
the application program (e.g. in MDA) for the compensation of the group run
-
time is no longer required.
To represent the group runtime for digital filters as an example, a test signal
was applied to an input.
The test signal is scanned with the sampling frequency f
S,INCA
= 2 kHz (0.5 ms).
The filter channel was set to the limit frequency f
C,FIR
= 200 Hz.
Fig. 6-2 ES930.1 Filter: f
C,FIR
= 200 Hz (with Group Runtime Compensation)
Fig. 6-2 on page 47 shows the respective signal path in the upper portion of the
figure without filter, in the lower portion of the figure with filter and group run-
time compensation.
6.4 Maximum Input and Common Mode Voltages
6.4.1 Definitions
The maximum input voltage between two inputs each and the maximum volt-
age between one input and the housing ground is 60 V DC/ 30 V AC. For an
explanation of the maximum input and common mode voltages, please
observe
Fig. 6-3 on page 48 and the calculation example.
All capacitors between the inputs (U
in+
and U
in-
) and the housing ground have
the same capacity. The maximum voltage between any input and case ground
is also 60
V DC/ 30 V AC.