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Editing of all objects in the process the D2000 CNF process is being performed in the configuration dialog box, a specific part of which is common for all editable objects and another part depends on the type of edited object.

Configuration The configuration dialog box of processes consists of several parts (tabs) containing the similar related parameters.

General properties
Groups
Archive
Statement
Time parameters
Conditions
Statistics
Filter

Kotva
zakladne_vlastnosti
zakladne_vlastnosti
General properties

...

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

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

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Selection of a value type of the historical value. The possible types are shown in the following table.

LabelValue type
Int-IntegerInteger
Re-RealReal
Bo-BooleanBoolean

Note: Value type may be defined for the archive purpose of a historical value of "Calculate archived values by defined statement" type only.

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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Technological limits are effective only for historical values which are calculated by D2000 Archiv (evaluated and statistical historical values). There are 4 limits defined: VHL, HL, LL, and VLL. Limit The limit can be defined either directly – by the value entry entered into the input field, or its value can be determined by a system object (dynamic limit) – the button right from the input field.

VHLVery High Limit - the highest limit
HLHigh Limit
LLLow Limit
VLLVery Low Limit - the lowest limit


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)

As the limits can be dynamic (determined by the object value), a situation when the relation VLL<LL<HL<VHL is not valid (the limits crossing) can occur. The historical value is then in the Limit Problem state.

Note: Changing the value of the dynamic limit will not cause a new evaluation of limits and possibly a new value with a changed Limits attribute. New The new value value of the dynamic limit is taken into account only when archiving a new value.

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There are the following options:

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  • Note: all types of Historical values (also primary, statistical, and evaluated) can be modified from an ESL script or manually from the process D2000 HI).

Kotva
parametre_archivacie
parametre_archivacie
Archiving parameters

The part of the configuration dialog box contains the following options:

The part of the configuration dialog box contains the following options:

  • Archive - if the option Archive is checked, then the defined object to archive will be archived. If it is not checked, the object will not be archived (the archiving is disabled).
  • Write Start/Stop - enables/disables automatic writing of START or STOP values.
  • Depository - the option allows to enable enabling/ disable disabling of storing values of the historical value into the depository database.
  • Kotva
    trezorsegment
    trezorsegment
    Depository segment - allows to specify the specifying the depository database segment the values to be stored in if the parameter Depository is checked. The parameter can be used for the Oracle platform with with depository database segments enabled or for the PostgreSQL platform with with depository database segments enabled.

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Kotva
ignore_identical
ignore_identical
Ignore identical

Optimisation Optimization of processing of old values processing of primary archives coming from communication (automatically or as a result of TELL command GETOLDVALthe GETOLDVAL command sent to the D2000 KOM process) or values of remote tags (as a result of TELL command GETOLDVAL sent to the D2000 Gateway Client process).
If the checkbox is checked, during the processing of the old value, the cache or archive database is queried whether the same value is already present there. If it exists, the value is discarded (and recalcs of statistical or calculated archived values which that use this primary archive value are not performed either).
Note: Optimisation is useful e.g. for archiving of I/O tags from communication using the protocol the IEC62056-21:2002 File I/O protocol. Its communication files contain several historical values (which the D2000 KOM process  process sends as old values) and one new value for every I/O tag.

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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 objectobjects. To open the list of object objects, click the button right from the input field.

Object to archive or value source may be:

  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 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 one. So all changes in the configuration of the historical value has directly 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 in defined time moments stores the archive object value into the archive in defined time moments. Timestamp (the time of value time) is not given determined by the occurrence time timestamp of the archive archived object value (e.g. an I/O tag), but by the time of when the value storing is periodically written into the archive.

    Reading the values stored periodically by means of the D2000 system (ESL: GETARCHARR, GETARCHVAL, GETARCHROWGETARCHCOL, GETARCHSTRUCTD2000 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 oversampling resampling and the begin (BT) and end (ET) time as follows:
    • oversampling resampling (step) = 0
      The reading results are all the values, the time of which belong into to the interval <BT, ET>.
    • oversampling resampling (step) <> 0
      The reading result is the value an array of values with timestamps continuouslycontiguously:
      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 (ET). The array value without value of the array item is invalid if a record with the same timestamps does not exist in the archive is invalid. The value with database. If such a record is filled according to it. The 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 for to some of the object archiving moments, given by the period and time offset of the archiving.
      • oversampling 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, from the reading point of view, acts periodicallyas far as reading is concerned, behaves as a periodical archive.
  • Kotva
    sa_filter1
    sa_filter1
    On value change
    - just all the value changes of the archive object undetected , which are not filtered out by the value filter, are stored into in the archive.

    Reading of values stored by using a filter 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 at any time (t) is given by (equalequals to) by the last historical value at or before the given time (t). The data reading result is therefore given by the oversampling the resampling and the begin (BT) and end (ET) time as follows:
    • oversampling  resampling (step) = 0
      The reading result results are all the values, the time of which belongs to the interval <BT, ET> and 1 one value before BT time, in case there is no value with a time exactly equal with BT  to BT time in the archive.
    • oversampling resampling (step) <> 0
      The reading result is a 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. The array value without any record If a record with the same timestamps does not exist in the archive with the same timestamp will be given by database, the value of the array item will be equal to the last value before the time requiredspecific required (however, the timestamp will be set accordingly).

Publish values

If the option the Publish values option is checked, then the historical value publishes its last archived value in the 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 an 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 the Target object parameter Target object.
  • When archiving a structured historical value - the last archived values of individual items are filled into the relevant items of a Structured variable type object defined by the the Target object parameter Target object.

Note: To ensure the correct functionality of the feature the Publish values feature for an a one-column historical value (resp. structured historical value), the number of rows (columns) in case of the structured variable defined in the parameter Target object 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.

Target object

The input field is enabled if the option 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, but 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.

Kotva
prepocet_stat_funkciou
prepocet_stat_funkciou
CALCULATE ARCHIVED VALUES BY STATISTICAL FUNCTION

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Definition of an object of Historical value type, values ofwhich are to be calculated. It can be:

  • simple HVhistorical value - simple historical value, item of one-column historical value (e.g. H.ColArchiv[2]) or item of structured historical value (e.g. H.Struct[2]^ColName),
  • one-column HVhistorical value - one-column historical value (e.g. H.ColArchiv) or column* of structured historical value (e.g. H.Struct[0]^ColName),
  • structured HVhistorical value - structured historical value.

* The list of columns is given by the respective structure definition, that which defines the structure of the historical value (e.g. H.Struct[2]^ColName).

Publish values

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

  • For a simple HVhistorical value - the object of the Historical value type you are configuring gets the last value (if unless the parameter Historical value is not defined).
  • When archiving an a one-column HV column historical value - the last archived values of individual items are filled into published in the relevant items of the column of a Structured variable type object defined by the the Target object parameter Target object.
  • When archiving a structured HVhistorical value - the last archived values of individual items are filled into published in the relevant items of a Structured variable type object defined by the parameter the Target object parameter.

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

Target object

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


Kotva
prepocet_zad_vyrazom
prepocet_zad_vyrazom
CALCULATE ARCHIVED VALUES BY DEFINED STATEMENT

The option allows to define defining a mathematic expression among containing objects of Historical value type (the tab the Statement tab). The expression can not contain the references to any current values of other D2000 system 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 the historical values H.Flow1 and H.Flow2. You If you need to archive the sum of both the flows. You , 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“.

Both the methods gives give the same result. A problem may occur , when you need to modify e.g. the value of the object H.Flow1 already , which is already archived. If you have used the first method, you must also manually change the value of the historical value. The second method automatically recalculates the expression and corrects the sum.

Calculation methods

So the D2000 Archive keeps the calculated (and also statistical) archives in synchronization with their source archives.

Calculation methods

Definition of a methods method to calculate 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 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.

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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 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 Structured variable type object. So, the number of rows of the historical value is given by the number of rows of the target column.

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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, or by other expression calculationcalculations. Values can be only filled from an ESL script or manually from the process the 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, but however, 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 It allows to define an object, that will contains contain values of the historical value - see the parameter the 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, attributes - but objects 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 a 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. 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 the necessity to read source data and calculate it for each read demandrequest. 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: 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
podmienka
podmienka
Conditions

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Defining the conditions for the start and interruption of the archiving is provided by provides the mechanism of dynamical control of the object archiving dynamical control , depending on the values or states of others 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 initialisation initialization of the process Archive.

Start condition

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

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

  • by writing the object in to 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" button.

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

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

The object representing the archiving stop condition may be defined by 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" button.

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

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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
of
to historical values.
SumSum of archive object values.
MaximumMaximum of archive object values.
MinimumMinimum of archive object values.
Count
Number
The number of archive object values.
FilterApplying a filter for value storing
into
in the statistical archive.
Increment
Increment between values.

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. The result will be the impulse multiplied by its weight.

Weight

A weight of 1 will

ensure

ensures standard behaviour.

DeltaDelta between values. Parameter (Compare value)the weight of impulse.
The result will be the impulse multiplied by its weight.
Weight
A weight of 1 will ensure standard behaviour.
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,
that
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
then
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 maximums
 
The number of local maximums in a given time interval.
Number of local minimums
 
The 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.
Parameter (
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.
Weight
A weight of 1 will ensure standard behaviour.
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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The difference among the functions INCREMENT, DELTA, and SUM OF INCREMENTS is shown in the following figures.

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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).

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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 valid values than stated in Validity criteria, the result will be Weak_Value.

Time interval for statistical calculation

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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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 the 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 statistical archive) that has to be valid, in order to acquire a valid result. If there were fewer valid values than stated in the Validity criteria, the result will be Weak_Value.


Time interval for statistical calculation

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 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 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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