User Manual

Trending
Trend functions
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The trend data is saved until the available memory area is full. You can define
the buffer size [BufSize] within the range 2 to 5,000 entries. You can define the
Single Run function with the parameter Stop when full.
The parameter Logging Type [LogTyp] defines the logging type. The values are:
● POLLED: Periodic Sampling
● COV: COV Sampling
● TRIGGERED: Triggered Sampling
By setting the parameters accordingly, you can define combinations of
Continuous Run / Single Run and Periodic Sampling / COV Sampling /
Triggered Sampling.
In Periodic Sampling data is acquired by sampling and storing values in a
regular cycle. Periodic Sampling is supported by the trend log object and the
trend log multiple object.
In COV Sampling data is stored based on a change of value (COV) of the
referenced parameter. A COV subscription can be applied to all supported data
types (analog, Boolean and multistate). The amount of change required to
initiate a COV is set as a parameter in the object to be referenced. COV
Sampling is supported only by the Trendlog object.
Single Run
Logging Type
Periodic Sampling
COV Sampling