5
Functional description
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gas-lab
Q1
5.3.1.4
Logging on measurement or counter archives
The Q1 is able to run archives for process values, i.e. archives for
measurements and count values. Up to four archive groups with up to 8
channels each are available. It can be determined for each archive group in
which conditions the contained archive channels shall be logged.
The standard procedure used is cyclic data logging (with configurable data
logging cycles of one second up to one hour).
Additionally or alternatively, the data logging can be made conditional upon
certain events occurring during the monitoring of the process values:
It is possible to link the data logging with one or more group(s) of single
messages. In this case the logging takes place upon the beginning and end
of each message contained in one of the involved groups.
If the development of a particular process value shall be logged in detail, a
maximum change rate can be defined for an archive channel. Then the
entire archive group is logged each time the difference between the current
measurement and the value measured during the last data logging exceeds
the maximum change rate. This way, the data is logged more often in case
of quickly changing values.
This option is also available for counter archives, which means you can
specify that the data logging shall always start when a count value has
increased by a defined difference.