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Configuration and operation
5.11 STEP 7 configuration of individual parameters
Error suppression time
An analog value in the overflow range (32767 / 7FFF
is not transferred for the duration of the error suppression time. This also applies to live zero
inputs. The value in the overflow/underflow range is only sent after the error suppression
time has elapsed, if it is still pending.
If the value returns to the measuring range before the error suppression time elapses, the
current value is transferred immediately.
A typical use case for this parameter is the suppression of peak current values when starting
up powerful motors that would otherwise be signaled to the control center as a disruption.
The suppression is adjusted to analog values that are acquired by the S7 analog input
modules as raw values. These modules return the specified values for the overflow or
underflow range for all input ranges (also for live zero inputs).
If mean value generation is active, this parameter has no effect.
Recommendation for finished values that were preprocessed by the CPU:
If the CPU makes preprocessed finished values available in bit memory or in a data block,
suppression is only possible or useful if these finished values also adopt the values listed
above 32767 / 7FFF
case, the parameter should not be enabled for preprocessed values.
Mean value generation
With this parameter, acquired analog values are transferred as mean values.
The current values of an analog data point are acquired cyclically and totaled. The number of
acquired values per time unit depends on the read cycle of the CPU and the CPU scan cycle
of the CP. The mean value is calculated from the accumulated values as soon as the
transfer is triggered by a time trigger. Following this, the accumulation starts again so that
the next mean value can be calculated.
The mean value can also be calculated if the transmission of the analog value message is
triggered by a request from the communications partner. The duration of the mean value
calculation period is then the time from the last transmission (for example triggered by the
trigger) to the time of the request. Once again, the accumulation restarts so that the next
mean value can be calculated.
50
or -32768 / 8000
in the overflow or underflow range. If this is not the
h
h
) or underflow range (-32768 / 8000
h
Operating Instructions, 02/2015, C79000-G8976-C384-01
)
h
CP 1243-1 PCC
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