Siemens SIMEAS R User Manual

6
6.1 Measured Value Acquisition and Processing
42 Digital Fault Recorder, SIMEAS R-PMU, Manual
E50417-H1076-C360-A5, Release 10.2012
6.1 Measured Value Acquisition and Processing
Figure 6-1 Measured value acquisition and processing
Sampling
AC and process signals of a data acquisition unit are digitized with a constant sampling rate of
192 sample values per nominal cycle. The binary signals are also read with a constant sampling
rate of 2 kHz and stored.
For further processing, the frequency is calculated first and then used to resample the sample
values.
This is not applicable for process values. Process values are zero-frequency values and are
therefore processed separately.
Nominal cycle duration
The nominal cycle duration T
n
is the reciprocal of the nominal system frequency f
n
: T
n
= 1/f
n
.
With a nominal system frequency of, e. g., 50 Hz, the nominal cycle duration is 20 ms. The cur-
rently measured cycle may differ from the nominal cycle.
SamplingAC signals
DC signals
Binary signals
Sampling
Sampling
Calculation of half-cycle
rms values
FFT
Measured and
trigger values
Measured and
trigger values
Trigger value
Measured value
Measured and
trigger values
Mean value calculation
Resam pling
Frequency calculation
Measured value
Measured and
trigger values

Siemens SIMEAS R Specifications

General

Brand	Siemens
Model	SIMEAS R
Category	Measuring Instruments
Language	English