Overview Of Supported Functions - Siemens SIMATIC PCS 7 Function Manual

Aggregate function
OPCHDA_MINIMUM
OPCHDA_MAXIMUMACTUALTIME
OPCHDA_MAXIMUM
OPCHDA_DELTA
OPCHDA_REGSLOPE
OPCHDA_REGCONST
OPCHDA_REGDEV
OPCHDA_VARIANCE
OPCHDA_RANGE
OPCHDA_DURATIONGOOD
OPCHDA_DURATIONBAD
OPCHDA_PERCENTGOOD
OPCHDA_PERCENTBAD
OPCHDA_WORSTQUALITY
6.4.6

Overview of supported functions

Introduction
The following tables list the functions supported by the OPC HDA server. These functions can
be used by the OPC HDA client for data exchange. Additional information is available in the
"OPC Historical Data Access Specification 1.20" of the OPC Foundation.
Function
ReadRaw
ReadProcessed
ReadAtTime
ReadAttribute
OpenPCS 7
Function Manual, 05/2012, A5E02780178-02
Description
Obtains the lowest value of the raw data for the specified
period.
Obtains the highest value and the time stamp of the raw data
for the specified period.
Obtains the highest value of the raw data for the specified
period.
Obtains the difference between the first and last value of the
raw data of the specified period.
Obtains the slope of the linear regression of the raw data for
the specified period.
Obtains the value of the linear regression of the raw data at
the start time.
Obtains the standard deviation of the linear regression of the
raw data for the specified period.
Obtains the variance of the raw data for the specified period.
Obtains the difference between OPCHDA_MAXIMUM and
OPCHDA_MINIMUM of the raw data for the specified period.
Obtains the period in which the quality of the raw data was
good. The period is entered in seconds.
Obtains the period in which the quality of the raw data was
bad. The period is entered in seconds.
Obtains the portion during which the quality of the raw data
was good as a percentage.
Obtains the portion during which the quality of the raw data
was bad as a percentage.
Obtains the worst quality of the raw data for the specified
period.
Description
Specifies the raw data, its quality and its time stamp for the specified period.
Returns the calculated value, the quality of the value and the time stamp
for the specified period. The calculated value depends on the selected
aggregate function.
Specifies the raw data, its quality and its time stamp for a specific point in
time. If no value exists, it is interpolated for this point in time.
Returns the attributes of the item and the time stamp for the specified period.
6.4 OPC Historical Data Access (OPC HDA)
OpenPCS 7 interface
51