Generic Item

The Generic Item object is used to periodically generate data or execute a Lua script. The generation period can be configured so the action is repeated every second, minute, hour, day etc.. There are different generation types, for example: numeric value, text, date and time or Lua script. In the case of the Lua script generation type, a custom Lua script is configured in the object properties and is executed periodically according to the generation period.

Use Cases

  • Periodically generate numbers, text or date values (in single or array form).

  • Measure or/and monitoring Performance Counters for specific items. This type of setting is frequently used in production environments.

  • Execute an embedded Lua script periodically.

  • Periodically trigger other object types

Quick Configuration

  1. Select a parent object and right-click. Select Admin  New  Data Processing  Generic Item.

  2. Enter an Object Name in the Create Generic Item wizard, then click Create.

  3. Select the object in the I/O Model and look at the Object Properties panel. By default, the generation type is set to Numeric Value Generator and the Generation Period to 1000 ms. In the faceplate, the number should incrementally increase from 0 to 100 (this can be configured in the Generation Type property compound).

For a further demonstration of how Generic Items can be used to work with other objects, please visit:

Object Properties

Common

Object Name

The user-modifiable object name. This name overrides the name which has been supplied by the external system. It must be unique within the collection of objects of the parent object.

Object Description

This is the user-modifiable object description. This text overrides the description which has been supplied by the external system.

System Alias

The system alias is an additional name for an object, which can be used as a shortcut for identification and has to be unique in the system.

Display Alias

Alternate label for objects to be used for easier identification in the displays.

Engineering Unit

The Engineering Unit or unit of measurement is a definite magnitude of a physical quantity, defined and adopted by convention or by law, that is used as a standard for measurement of the same physical quantity.

Decimal Places

The maximum number of decimal digits that will be displayed to the right of the decimal point.

Access Rights

Server side defined access rights.

  • Readable: The server allows for external reads.

  • Writeable: Server allows for external writes.

Generation Period

This value defines the update interval of the value generation. The minimum is 100 milliseconds. If this value is equal to the Function Period, the generated value will be constant.

Dedicated Thread Execution

When set, the item executes in a thread not shared with other items.

Attachments

File attachments stored in MongoDB file store.

Usecases

Lists the usecases that apply to this object.

Limit Settings

Define limits for EU range and alarming.

Low EU Range

Low EU Range.

High EU Range

High EU Range.

Low Limit

Alarming low limit.

High Limit

Alarming high limit.

Deadband Settings

Configure the deadband filtering of the dynamic value.

Deadband Type

Specifies how the deadband parameter should be interpreted.

  • Absolute: Defines deadband parameter as absolute value.

  • Percent: Defines deadband parameter as percentual value.

  • None: Deadband will be not used.

Absolute Deadband

The absolute deadband.

Percent Deadband

The percent deadband. Relative to the Low and High EU Range.

Unfiltered Value

The original dynamic value without any filtering.

Generation Type

Select the generation type.

Numeric value generator

A function that generates numeric values.

Numeric Date and Time Function Value Generator

A function that generates numeric date and time values.

Textual Generation

Can be used to generate text.

Textual Date and Time Function Value Generator

A function that generates textual date and time values.

Lua Script Data Generator

A function that generates values from Lua scripts.

Host Environment Values

The environment value generation can be used for Simulation, Script-based data generation and more.

Performance Counter Assignment

Used to assign performance counters.

Archive Options

Selection between different archive options.

Archive Selection

Select default archive of the master core or a custom set of data stores.

Storage Strategy

Summarizes the settings for historization, aggregration and forecasting for a particular ItemValue.

  • Raw History: ItemValue is stored in Raw History Collections.

  • Aggregation 1 min: ItemValue is stored in 1-minute Aggregation Record Collections.

  • Aggregation 5 min: ItemValue is stored in 5-minute Aggregation Record Collections.

  • Aggregation 10 min: ItemValue is stored in 10-minute Aggregation Record Collections.

  • Aggregation 15 min: ItemValue is stored in 15-minute Aggregation Record Collections.

  • Aggregation 1 h: ItemValue is stored in hourly Aggregation Record Collections.

  • Aggregation 1 day: ItemValue is stored in daily Aggregation Record Collections.

Persistency Timeout

When set, the persisted dynamic value is not used if it is older than the specified timeout in seconds (e.g. 86400 would be the correct setting to persist the dynamic value for a maximum of one day). If not set, no timeout is used.

Auxiliary State Management

Configurable settings for auxiliary state management.

Strategy

Specifies how auxiliary state changes are handled.

  • Inherit: Inherit the setting from the parent object. In case of no parent object, the "Persist" mode is used.

  • Persist: All object auxiliary states are indicated and persisted to the archive.

  • Volatile: Auxiliary state changes are volatile and not persisted.

  • Inhibit: Inhibit all auxiliary state changes.

Location

The location of the object.

Strategy

Definition of the location strategy.

  • No location: This object is not interpreted in a location context.

  • Static (or manually changed) location: You may set the location data manually, by Engineering Script or by selecting the location visually using the Location Finder feature.

  • Inherited location: The object inherits the location from the owning object in the system hierarchy.

  • Dynamic location: The object location is supplied by other I/O Items. You may drop other I/O items into the location fields of this object.

  • Location properties: The endpoint server has distinct properties for I/O item location data. Please note, that this option works only for I/O items .

Name

The optional name of a location.

Latitude

The north-south position of a point on the Earth’s surface.

Longitude

The east-west position of a point on the Earth’s surface.

Altitude

The height above sea level of the location.

Track Location

Enables historization of Location data.

Lifecycle Management

Lifecycle Management.

Object Maturity

This selection classifies the productive state of the object. It can be used in conjunction with catalogue functions in order to identify specific objects in respect to their maturity state.

  • Test (Sandbox): The object currently fulfills test purpose.

  • Development: The object is currently under development.

  • Qualification: The object is part of a qualification use case.

  • Production: The object is part of a productive use case.

  • Expendable: The object implements functionality which is not crucial to system operation.

  • Removable: The object can be removed by automated cleanup tasks.

Custom Options

Compound to hold various structures to customize the object and to be read and written to by Lua-Script code or external interfaces.

Custom String

A generic string buffer to be used programmatically for custom purposes.

Custom Properties

This is an extensible set of named strings which can be used programmatically for custom purposes.

Property Name

A custom property name which can be used programmatically.

Property Value

The value of the custom property which can be read and written programmatically.

Custom Tables

This is an extensible set of named tables which can be used programmatically for custom purposes.

Table Name

A custom table name which can be used programmatically.

Table Data

Handles an entire table organized in columns and rows. The data can easily (cut, copy and paste) be exchanged with table-oriented data of other software products, e.g. MS Excel.