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A text string describing the historical value. Maximum: 128 characters.
Possibility to use the Dictionary (to open click the CTRL+L).

Status Text

Defines a status text of the historical value. The status text allows for redefining individual values' identification for the historical value.

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Technical units

Technical units of the historical value. Maximum: 12 symbols. Possibility to use the Dictionary (to open click the CTRL+L).

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Values of the individual limits determine the state of the historical value according to its value. The relation value- limits gives give six possible states.

LimitObject state according to relation Value - Limit

Above VHL (object value > VHL)
VHL

Above HL (HL < object value < VHL)
HL

Normal (LL < object value < HL)
LL

Bellow LL (VLL < object value < LL)
VLL

Bellow VLL (object value < VLL)

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Definition of a D2000 system object, values of which are to be archived. The object may be defined either by typing its name into the input edit field or by selecting it from the list of objects. To open the list of objects, click the button right from the input field.

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  1. An object, the value of which is a simple type (Integer, Boolean, Real,...) - just one value is archived, therefore such archived object is called a simple historical value.
  2. An item of an object of Structured variable type - there is also just one value archived, therefore such archived object is called a simple historical value, too.
  3. A column of an object of Structured variable type (e.g. SV.Strct[0]^ColName) - there are archived all values of the column. Such an archived object is called a one-column historical value.
  4. An entire object of Structured variable type (e.g. SV.Struct) - there are archived all values of the object. Such an archived object is called a structured historical value.

Note: The above-described fact implies, that the object to archive directly specifies the type of historical value - simple, one-column, or structured historical oneones. So all changes in the configuration of the historical value have a direct effect on its functionality, mainly if the object is used in other historical values.

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  • Periodical  - writing values into in the archive is are periodical. The archiving process stores the archive object value into in the archive in defined time moments. Timestamp (the time of value) is not determined by the timestamp of the archived object value (e.g. an I/O tag), but by the time when the value is periodically written into the archive.

    Reading the values stored periodically by means of the D2000 system (ESL: GETARCHARR, GETARCHVAL, GETARCHROWGETARCHCOLGETARCHSTRUCTD2000 ObjApi: GetArchivData, D2000 VBApi: VBApiGetArchData, D2000 WorkBook) follows the rule that the archive object's value out of time moments given by the period, is unknown (invalid). The result of the data reading is therefore given by the resampling and the begin (BT) and end (ET) time as follows:
    • resampling (step) = 0
      The reading results are all the values, the time of which belong into belongs to the interval <BT, ET>.
    • resampling (step) <> 0
      The reading result is an array of values with timestamps contiguously:
      BT+0*step, BT+1*step, BT+2*step, ..., BT+N*step.
      The number of values is given by the end of the time interval (ET). The value of the array item is invalid if a record with the same timestamps does not exist in the archive database. If such a record exists, it is returned as a value of the array item. The above facts imply that when reading periodical data, it is necessary (advisable):
      • to adjust BT exactly to some of the object archiving moments, given by the period and time offset of the archiving.
      • resampling value (step) must be an integer multiple of the archiving period.
      • ET = BT + (N-1)*step, where N is an integer number: the number of values in the final selection.

      Note: The statistical archive, as far as reading is concerned, behaves as a periodical archive.
  • Kotva
    sa_filter1
    sa_filter1
    On value change
    - all the value changes of the archive object, which are not filtered out by the value filter, are stored in the archive.

    Reading of values stored by using a filter by means of the D2000 system (ESL:   GETARCHARR, GETARCHVALGETARCHROWGETARCHCOLGETARCHSTRUCTD2000 ObjApi: GetArchivData, D2000 VBApi: VBApiGetArchData, D2000 WorkBook) follows the rule that the archive object's value at any time (t) is given by (equals to) the last historical value at or before the given time (t). The data reading result is therefore given by the resampling and the begin (BT) and end (ET) time as follows:
    • resampling (step) = 0
      The reading results are all the values, the time of which belongs to the interval <BT, ET> and one value before BT time, in case there is no value with a time exactly equal to BT time in the archive.
    • resampling (step) <> 0
      The reading result is an array of values with timestamps continuously:
      BT+0*step, BT+1*step, BT+2*step, ..., BT+N*step.
      The number of values is given by the end ET of the time interval. If a record with the same timestamps does not exist in the archive database, the value of the array item will be equal to the last value before the specific required (however, the timestamp will be set accordingly).

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If the Publish values option is checked, then the historical value publishes its last archived value in the a way, that depends on the object to archive, as follows:

  • For a simple historical value - the object of the Historical value type gets the last value.
  • When archiving a one-column historical value - the last archived values of individual items are filled into the relevant items of the column of a Structured variable type object defined by the Target object parameter.
  • When archiving a structured historical value - the last archived values of individual items are filled into the relevant items of a an object of Structured variable type object , defined by the the Target object parameter.

Note: To ensure correct functionality of the Publish values feature for a one-column historical value (resp. structured historical value), the number of rows (in case of a structured historical value, also the number of columns) of the structured variable defined in the Target object parameter must be the same as the number of rows (columns) of the object defined by the parameter Object to archive.

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The input field is enabled if the Publish values option is checked. It allows you to define an object, that will contains values of the historical value. When archiving a simple historical value, the target object must not be defined. However, it must be defined for one-column historical value, and for structured historical value - the size of the target object must be the same as the size of the object defined by the parameter Object to archive.

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If the Publish values option is checked, then the historical value publishes its last archived value in the a way, that depends on the object defined by the parameter Historical value as follows:

  • For a simple historical value - the object of the Historical value type you are configuring gets the last value (unless the parameter Historical value is defined).
  • When archiving a one-column historical value - the last archived values of individual items are published in the relevant items of the column of a Structured variable type object defined by the Target object parameter.
  • When archiving a structured historical value - the last archived values of individual items are published in the relevant items of a Structured variable type object defined by the Target object parameter.

Note: To ensure the correct functionality of the Publish values feature for a one-column historical value (structured HV) the number of rows (columns) of the structured variable defined in the Target object parameter must be the same as the number of rows (columns) of the object defined by the Historical value parameter.

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The input field is enabled if the Publish values option is checked. It allows you to define an object, that will contains values of the historical value. When archiving a simple historical value, the target object must not be defined. However, it must be defined for one-column historical value and for structured historical value (see the Historical value parameter) - the size of the target object must be the same as the size of the object defined by the parameter Historical value.

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The option allows defining a mathematic expression containing objects of Historical value type (the Statement tab). The expression can not contain references to any other D2000 objects. Calculation of the expression provides values to be archived.

For example:
We have got two measurement points - two I/O tags, which are archived as historical values H.Flow1 and H.Flow2. If you need to archive the sum of both the flows, you can use two methods:

  1. Create an object of Eval tag type, that adds together the values of the I/O tags and then archive archives it.
  2. Create an object of Historical value type with the expression of „H.Flow1 + H.Flow2“.

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Calculation methods

Definition of a methods method to calculate a given expression - periodically or on value change. If the option On value change is option is selected, the expression will be recalculated when a value of at least one of the objects defined in the expression is changed.

Object An object of Historical value type defined in this way can be either simple or one-column historical value. If the object is one-column historical value, the expression may also contain the references to other structured or one-column historical values with the a row index of 0. During the calculation, the index is dynamically replaced by the current row number of the one-column historical value to recalculate. That allows to define defining the same expression for all column items.
Example of a structured expression: H.SourceColumn[0] + H.SourceStruct[0]^ColA

Kotva
zverejnovat
Kotva
zverejnovat_hodnoty
zverejnovat_hodnoty
Publish values

If the option Publish values is checked, than then the historical value will publish its last value:

  • If the option is not checked, the parameter Structure size defines whether the historical value is is simple or a one-column one.
    If Structure size is not defined, the historical value is a simple one. If it is defined, the object is one-column historical value - it is possible to define a column of a Structured variable type object, a column of a structured historical value, or a one-column historical value. The number of rows of the calculated one-column historical value is given by the number of rows of the objects defined in the parameter Structure size.
  • If the option is checked, the parameter Target column specifies whether the calculated historical value is simple or one-column.
    If the Target column is not defined, the historical value will be a simple one that gets the last value.
    If it is defined, the object will be a one-column historical value - it is possible to define a column of a an object of Structured variable type object. So, the number of rows of the historical value is given by the number of rows of the target columnstructured variable.

Archive size

Definition of archive size - see the parameter the Publish values parameter. The parameter will appear, if the parameter be visible only if the Publish values parameter is not checked.

Target column

Definition of an object, that will contain values of the historical value - see the parameter the Publish values parameter. The parameter will appear, if the option will be visible only if the Publish values option is checked.


Kotva
archiv_plneny_skriptom
archiv_plneny_skriptom
FILL ARCHIVE FROM SCRIPT (VALUE STORAGE)

Object An object of Historical value type filled from a script can be used as a storage of values which that are not generated by archiving the values of other D2000 system objectobjects, statistical calculation calculations, or by other expression calculationcalculations. Values can be only filled from an ESL script or manually from the process D2000 HI process.

Value storage can be simple, one-column, or structured one. This is given defined by the parameter Archive structure or Target structure (it depends on the parameter Publish values)

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If the option is checked, you must define a period and offset (the tab the Time parameters tab).

Kotva
zverejni_hodnoty
zverejni_hodnoty
Publish values

Checking the option Publish values "renames" the parameter Archive structure to Target structure. The functionality of the parameter to define the structure of the archive is not changed, however, but it is not possible to define an object of Historical value type.
If the option the Publish values option is checked, the parameter Target structure defines whether the historical value is simple or or structured one. If the Target structure is not defined, the historical value is a simple one and gets the last value. If it is defined, the historical value is a structured one and will fill publish the last value into the respective item of a defined structured variable.

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The parameter is enabled when the parameters Inserted values are periodical and Publish values are checked. If it is checked, the historical value will not publish its last value but the value that is valid according to the current time. (This feature supports storing data with future timestamps in an object of Historical value type - e.g. from a an ESL script , the feature allows to fill an object of Historical value type with values containing the future timestamps and - and then the object "plays" them these values in real-time).

Archive structure

The parameter appears when the the Publish values parameter Publish values is not checked.

  • If it is not defined, the historical value is a simple one.
  • The historical value is a one-column one , if the parameter contains:
    • column of a structured historical value (e.g. H.Struct[0]^ColName)
    • one-column historical value (e.g. H.ColArchiv)
    • column of an object of Structured variable type (e.g. . SV.Struct[0]^ColName)
  • The historical value is a structured one , if the parameter contains:

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The parameter will appears if the parameter the Publish values parameter is checked. Allows to define It allows defining an object, that will contains contain values of the historical value - see the parameter Publish values parameter. If it is not defined, the historical value itself will contain the values.

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In the top part of the tab, there an input edit field is placed the input edit filed . It serves for entering the expression, that determines the value of the historical value. The expression can contains contain functions, constants, and attributes - but objects must be of Historical value type only. The expression may also contain the contain extended syntax.

Objects

The button allows to select selecting an object of the D2000 system. Selected The selected object is to be inserted into the expression on the current cursor position.
Note: Expression can contain objects of Historical value type only.

Constants

The button allows to select selecting a constant. Clicking it open opens the dialog box containing the list of predefined constantconstants. Selected The selected constant is to will be inserted into the expression on the current cursor position.

Functions

The button allows to select selecting a function. Clicking it opens the "List of functions" dialog box. Selected The selected function is to be inserted into the expression on the current cursor position.

Attributes

The button allows to select allows selecting an attribute. Clicking it open opens the dialog box containing the list of attributes. Selected The selected attribute is to be inserted into the expression on the current cursor position.

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If checked, all invalid values of the objects defined in the expression will be replaced with the value of 0. The feature can be used to prevent the expression from getting invalid value. There are converted just values. Only the values of input objects are replaced, and invalid values of intermediate data are not convertedreplaced. Values of inputs input objects are converted as follows:

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The parameter can be defined for the archive method Filter. It allows to restrict restricting the number of evaluations of a given expression so that the expression will be evaluated once within defined time. It is used especially in cases, when the values of the objects defined in the expression are often changed and calculating the expression is not required immediatelya defined time to reduce CPU and disk I/O usage. It is used especially in cases , when the values of the objects defined in the expression are often changed, and calculating the expression is not required immediately.

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  • Continuous - continuous (on the fly) calculation. Result values are calculated on the fly and they are automatically available (in dependence depending on the system load). A disadvantage of the method is a higher demand on the for computing power (especially for frequent changes of primary historical values that enter into the expression).
  • On demand - the calculation is executed and the result is stored to in the archive on demand. The demand can be generated by the the CALCONDEMANDSTAT action CALCONDEMANDSTAT or by the Tell command RECALC command ).
    Note: historical value values calculated "on-demand" should not have any depending on historical values calculated continuously, because the result  because their results would be wrong.
  • On read - the calculation is executed as a result of a read request. An advantage of this method is that values are not stored in the database so they don't occupy any disk space. There is no possibility of re-calculation in case of writing delayed data into the archive. A disadvantage is a necessity to read source data and calculate it for each read demand.
    Note: historical value calculated on read should request. This method should be used for objects whose values are rarely needed.
    Note: historical value calculated "on-read" should not have any depending historical values calculated continuously or "on-demand", because the result could be wrong in some cases (due to delayed data) or the calculation could be ineffective (multiple calculations of a single "on-read" object if it is used by several other historical values).

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Archiving time (Months: Days: Hours). The parameter determines the archiving time depth. It is the minimal time period, during which the data will be stored in the on-line online archive. The older data are being erased from the archive.

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For periodical data archiving, it is defined, defines what time data with the value for the given period will be stored into in the archive. The time data can present either the begin beginning time - the "Period begin" option or the end time of the interval (period) - the "Period end option" option.

Note 1: For For archives filled from the script, this setting does not directly affect anything - the data has a time stamp timestamp with which it was stored from the script. It however affects the calculation of statistics and whether statistics are calculated from the value at the edge of the interval.

Kotva

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graphs

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Defining the conditions for the start and interruption of the archiving is provided by the mechanism of the object archiving dynamical control depending on values or states of others objects in the system. Both conditions need not have to be defined. If not defined, the archiving will be started immediately after the start and initialisation of the process Archive.

Start condition

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  • writing the object in to the input field,
  • selecting the object from the list of objects - the list opened after clicking the button right from the input field,
  • creating a new object - Create new object button.

Also, it is necessary to define, for what state of the given object is the condition valid. In the list under the object entry field, there are displayed possible object value states. This list is different for various  kinds of types of objects. The archiving start condition will be valid, if the object is in the chosen state. If the option Inverse function is enabled, the condition is valid, if the object is in status other than the chosen state.

Stop condition

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  • writing the object name into the input field,
  • selecting the object from the list of objects - the list is opened by clicking the button right from the input field,
  • creating a new object - Create new object button.

Also, it is necessary to define, for what state of the given object is the condition valid. In the list under the object entry field, there are displayed possible object value states. This list is different for various  kinds of types of objects. The archiving stop condition will be valid, if the object is in the chosen state. If the option Inverse function is enabled, the condition is valid, if the object is in status other than the chosen state.

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graphs
Note 2: when displaying data in graphs, the parameter "Stored time" is taken into account:

  • for primary periodic archives, the value is plotted for the entire period (regardless of whether the start or end time is stored)
  • for statistical archives, the value is plotted for the entire period (regardless of whether the start or end time is stored).
    The exception is the "time slice", which depends on the value of the parameter "Stored time":
    • if "Period begin" is set, the value for period <T, T+Period> has timestamp T and is plotted for period <T, T+Period>
    • if "Period end" is set, the value for period <T, T+Period> has timestamp T+Period and is plotted for period <T+Period, T+2*Period>
  • for script-filled archives, it depends on the value of the parameter "Stored time":
    • if "Period begin" is set, the value with time T is plotted for period <T, T+Period>
    • if "Period end" is set, the value with time T is plotted for period <T-Period, T>

Kotva
podmienka
podmienka
Conditions

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Defining the conditions for the start and interruption of the archiving provides the mechanism of dynamical control of the object archiving, depending on the values or states of other objects in the system. Both conditions need not have to be defined. If not defined, the archiving will be started immediately after the start and initialization of the process Archive.

Start condition

Definition of the condition causing the start archiving of the given historical value.

The object representing the archiving start condition may be defined in several ways:

  • by writing the object into the input field,
  • by selecting the object from the list of objects - the list is opened after clicking the button right from the input field,
  • by creating a new object - the "Create new object" button.

Also, it is necessary to define, for what state of the given object the condition is valid. In the list under the object entry field, the possible object value states are displayed. This list is different for specific types of objects. The archiving start condition will be valid if the object is in the selected state. If the option Inverse function is enabled, the condition is valid, if the object is in a status other than the chosen state.

Stop condition

Defining the condition that causes stopping the archiving of the given historical value.

The object representing the archiving stop condition may be defined in several ways:

  • by writing the object name into the input field,
  • by selecting the object from the list of objects - the list is opened by clicking the button right from the input field,
  • by creating a new object - the "Create new object" button.

Also, it is necessary to define, for what state of the given object the condition is valid. In the list under the object entry field, the possible object value states are displayed. This list is different for specific types of objects. The archiving start condition will be valid if the object is in the selected state. If the option Inverse function is enabled, the condition is valid, if the object is in a status other than the chosen state.

Kotva
statistika
statistika
Statistics

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Kotva
stat_funkcia
stat_funkcia
Statistical function

When archiving into the statistical archive, it is possible to use these implemented functions.

FunctionMeaning
NoneNo function.
Average *Arithmetical average of all archive object values.
W-Average *Weighted arithmetical average of all archive object values.
IntegralTime is integral to historical values.
SumSum of archive object values.
MaximumMaximum of archive object values.
MinimumMinimum of archive object values.
CountThe number of archive object values.
FilterApplying a filter for value storing in the statistical archive.
Increment

If the newer value is greater than the older one, then the difference between the values, otherwise the newer value (the function is useful to process counter values that overflow and start from zero again).
Parameter (Compare value) – the weight of impulse.

When archiving into the statistical archive it is possible to use these implemented functions.

FunctionMeaning
NoneNo function.
Average *Arithmetical average of all archive object values.
W-Average *Weighted arithmetical average of all archive object values.
IntegralTime integral of historical values.
SumSum of archive object values.
MaximumMaximum of archive object values.
MinimumMinimum of archive object values.
CountNumber of archive object values.
FilterApplying a filter for value storing into the statistical archive.
Increment

If the newer value is greater than the older one, then the difference between the values, otherwise the newer value (the function is useful to process counter values that oveflow and start from zero again).
Parameter (Compare value) – weight of impulse. The result will be the impulse multiplied by its weight. Weight of 1 will ensure standard behaviour.

DeltaDelta between values. Parameter (Compare value) – weight of impulse.
The result will be the impulse multiplied by its weight. Weight of 1 will ensure standard behaviour.
EcoAvgAverage of the object values within the elapsed time period (Period parameter in Time parameters tab) according the methodology based on flags of individual values entering the statistic. The same purpose is fulfilled by the function %EcoAveR, that is implemented for eval tags.
GT Time (>)The function calculates the time, during which the value of the historical value was greater than the entered constant (Compare value).
GE Time (>=)The function calculates the time, during which the value of the historical value was greater or equal to the entered constant (Compare value).
LT Time (<)The function calculates the time, during which the value of the historical value was lower then the entered constant (Compare value).
LE Time (<=)The function calculates the time, during which the value of the historical value was lower or equal to the entered constant (Compare value).
Maximum in time intervalObsolete - do not use!
Minimum in time intervalObsolete - do not use!
Number of local maximumsNumber of local minimums
Sum of positive valuesSum of positive values of the historical value.
Sum of negative valuesSum of negative values of the historical value.
Average of positive valuesArithmetical average of positive values of the historical value.
Average of negative valuesArithmetical average of negative values of the historical value.
Sum of incrementsSum of increments for given time interval. If the new value is less than the old value, the increment is 0.
Parameter (Compare value) – weight of impulse.

The result will be the impulse multiplied by its weight.

Weight

A weight of 1 will

ensure

ensures standard

behaviour

behavior.

Time slice**Object value in given time moments.
Sample standard deviationThe function calculates the sample standard deviation of all values of the archive object.

* For non-periodical values we recommend you to use the W-Average (weighted average) function and the Average function for periodical values.
** The function allows recalculation of the historical value if historical values archived primarily have been changed.

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In the first case, all three functions are equal to 5 (10-5)

In the second case

  • DELTA = 5-10 = -5
  • INCREMENT = 5 (because 5 <10)
  • ADDITIONAL AMOUNT = 0 (because 5 <10)

In the third case

  • DELTA = (10 - 5) + (2 - 10) + (10 - 2) = 5
  • INCREMENT = (10-5) + 2 (because 5 <10) + (10-2) = 15
  • ADDITIONAL AMOUNT = (10-5) + 0 (because 5 <10) + (10 - 2) = 13

...

Statistics calculation method:

  • Continuous - continuous (on the fly) calculation. Result values are calculated on the fly and they are automatically available (in dependence on the system load). A disadvantage of the method is a higher demand on the computing power (especially for frequent changes of primary historical values).
  • On demand - calculation is executed and result is stored to the archive on demand. The demand can be generated by the action CALCONDEMANDSTAT or the Tell command RECALC). Note: historical value calculated on demand should not have any depending historical values calculated continuously, because the result would be wrong.
  • On read - calculation is executed as a result of a read request. An advantage of the method is that values are not stored in the database so they don't occupy any disk space. There is no chance of wrong calculation in case of writing delayed data into the archive. A disadvantage is a necessity to read source data and calculate it for each read demand.
    Note: historical value calculated on read should not have any depending historical values calculated continuously or on demand, because the result could be wrong (due to delayed data) or the calculation could be ineffective (multiple calculations of a single on read object if it is used by several other historical values).

...

DeltaDelta between values. Parameter (Compare value) – the weight of impulse.
The result will be the impulse multiplied by its weight. A weight of 1 will ensure standard behavior.
EcoAvgAverage of the object values within the elapsed time period (Period parameter in Time parameters tab) according to the methodology based on flags of individual values entering the statistic. The same purpose is fulfilled by the function %EcoAveR, which is implemented for eval tags.
GT Time (>)The function calculates the time, during which the value of the historical value was greater than the entered constant (Compare value).
GE Time (>=)The function calculates the time, during which the value of the historical value was greater or equal to the entered constant (Compare value).
LT Time (<)The function calculates the time, during which the value of the historical value was lower than the entered constant (Compare value).
LE Time (<=)The function calculates the time, during which the value of the historical value was lower or equal to the entered constant (Compare value).
Maximum in the time intervalObsolete - do not use!
Minimum in the time intervalObsolete - do not use!
Number of local maximumsThe number of local maximums in a given time interval.
Number of local minimumsThe number of local minimums in a given time interval.
Sum of positive valuesSum of positive values of the historical value.
Sum of negative valuesSum of negative values of the historical value.
Average of positive valuesArithmetical average of positive values of the historical value.
Average of negative valuesArithmetical average of negative values of the historical value.
Sum of incrementsSum of increments for a given time interval. If the new value is less than the old value, the increment is 0.
Parameter (Compare value) – the weight of impulse.
The result will be the impulse multiplied by its weight. A weight of 1 will ensure standard behavior.
Time slice**Object value in given time moments.
Sample standard deviationThe function calculates the sample standard deviation of all values of the archive object.

* For non-periodical values we recommend using the W-Average (weighted average) function, for periodical values the Average function is appropriate.
** The function allows recalculation of the historical value if historical values archived primarily have been changed. In addition, the time of the end of the interval is always stored (this 'statistics' basically only resamples the source archive with the selected period).


The difference among the functions INCREMENT, DELTA, and SUM OF INCREMENTS is shown in the following figures.

Image Added

In the first case, all three functions are equal to 5 (10-5)

In the second case

  • DELTA = 5-10 = -5
  • INCREMENT = 5 (because 5<10)
  • SUM OF INCREMENTS = 0 (because 5<10)

In the third case

  • DELTA = (10 - 5) + (2 - 10) + (10 - 2) = 5
  • INCREMENT = (10-5) + 2 (because 5<10) + (10-2) = 15
  • SUM OF INCREMENTS = (10-5) + 0 (because 5<10) + (10 - 2) = 13

Kotva
vypocet_statistika
vypocet_statistika
Calculation

Statistics calculation method:

  • Continuous - continuous (on the fly) calculation. Result values are calculated on the fly and they are automatically available (depending on the system load). A disadvantage of the method is a higher demand for computing power (especially for frequent changes of primary historical values that enter into the expression).
  • On demand - the calculation is executed and the result is stored in the archive on demand. The demand can be generated by the CALCONDEMANDSTAT action or by the RECALC command ).
    Note: historical values calculated "on-demand" should not have any depending on historical values calculated continuously because their results would be wrong.
  • On read - the calculation is executed as a result of a read request. An advantage of this method is that values are not stored in the database so they don't occupy any disk space. There is no possibility of re-calculation in case of writing delayed data into the archive. A disadvantage is a necessity to read source data and calculate it for each read request. This method should be used for objects whose values are rarely needed.
    Note: historical value calculated "on-read" should not have any depending historical values calculated continuously or "on-demand", because the result could be wrong in some cases (due to delayed data) or the calculation could be ineffective (multiple calculations of a single "on-read" object if it is used by several other historical values).

Kotva
validation_criteria
validation_criteria
Validation criteria

The value of the parameter Validation criteria defines the value percentage in the primary archive (used for the calculation of values stored in The value of the parameter Validation criteria defines the value percentage in the primary archive (used fro the calculation of values stored into the statistical archive) that has to be valid, in order to acquire a valid result. If there were less fewer valid values than stated in the Validity criteria, the result will be Weak_Value.

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Statistical time period defines the time interval, the set of historical values, that will be processed by the particular statistical function. By default, the interval is equal with the archiving period. If it is necessary to enter different period, check the option Time interval different from archiving period and enter required period into the parameter Interval. The time period must be greater than 0 [s].

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A parameter for the functions GT Time (>), GE Time (>=), LT Time (<), LE Time (<=).

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function. By default, the interval is equal to the archiving period. If it is necessary to enter a different period, check the option Time interval different from archiving period and enter the required period into the parameter Interval. The time period must be greater than 0 [s].

Kotva
compare_value
compare_value
Compare value

A parameter for the functions GT Time (>), GE Time (>=), LT Time (<), LE Time (<=).

Kotva
integral_time_units
integral_time_units
Integral time units

A parameter for the function INTEGRAL:

  • Hours - hour integral
  • Minutes - minute integral
  • Seconds - second integral

Kotva
hranicne_hodnoty
hranicne_hodnoty
Include edge values

This parameter (available from D2000 version 22) determines whether a value with an interval start/end time enters the calculation. The parameter is configurable for functions:

  • Average
  • Sum
  • Maximum
  • Minimum
  • Count
  • EcoAvg
  • Maximum in the time interval
  • Minimum in the time interval
  • Sum of positive values
  • Sum of negative values
  • Average of positive values
  • Average of negative values
  • Sample standard deviation

It cannot be configured for other functions:

  • W-Average
  • Integral
  • Filter
  • Increment
  • Delta
  • GT Time (>)
  • GE Time (>=)
  • LT Time (<)
  • LE Time (<=)
  • Number of local maximums
  • Number of local minimums
  • Sum of increments
  • Time slice

A parameter for the function INTEGRAL:

  • Hours - hour integral
  • Minutes - minute integral KotvafilterfilterSeconds - second integral Kotvafilterfilter

Kotva
filter
filter
Filter

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The system allows to archive considerable value changes archiving of significant changes in the values of the archive archived object. This archiving method represents defining of three deadband levels, that are possible to set various values of significant changesmethod of archiving represents the definition of three sensitivity bands in which it is possible to enter different values of a significant change.



Values of filtering:

  • High limit - defining the high limit for filtering.
  • Low limit - defining the low limit for filtering.
  • Above limit - defines a significant change of the archive object for value above the high limit.
  • In limit - defines a significant change of the archive object for value within the the lower and high limits.
  • Below limit - defines a significant change of the archive object for value below the low limit.


Info
titleRelated pages:

Historical values

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