Plugin: Basic Reference Data Module
A measurement unit is a basic definition of what you are measuring with a parameter. Units are expressions of the magnitude of associated physical quantities.
Open the Measurement Units browser by selecting the Measurement Units icon on the Reference Data tab. Measurement Units are given with a Short Name, a Name, Type, and Container RDL. Measurement Units can be of the following types1:
Specialization of measurement unit that represents a measurement unit that does not depend on any other measurement unit
Example: "gram", "metre"1
Specialization of Measurement Unit that is defined as a product of powers of one or more other measurement units
Example 1: The measurement unit "metre per second" for "velocity" is specified as the product of "metre" to the power one times "second" to the power minus one.
Example 2: The measurement unit "micrometre per metre" for the DerivedQuantityKind "linear expansion coefficient" is specified as the product of (PrefixedUnit) "micrometre" to the power one times (SimpleUnit) "metre" to the power minus one.1
Linear Conversion Unit
Specialization of ConversionBasedUnit that represents a measurement unit that is defined with respect to another reference measurement unit through a linear conversion relation with a conversion factor
Example: In the definition of the LinearConversionUnit for "inch" with respect to the referenceUnit "metre", the conversionFactor would be 254/10000, because 0.0254 metre = 1 inch.1
Specialization of ConversionBasedUnit that defines a measurement unit with a multiple or submultiple UnitPrefix
Example: Measurement units like "kilogram", "millimetre", "nanovolt", "gibibyte" etc.1
Persons with a role that has the permission Modify on the ClassKind Site Reference Data Library are able to access the Basic RDL to create, edit or delete measurement units. The measurement units can be used in the definition of measurement scales.
A description of the available functionalities is given below. Next to these it is possible to use the generic functionality using the Search and Help icons. To make sure the latest data is shown in the browser, it is always possible to refresh it using the Refresh icon. The measurement unit modal dialogs further have the generic functionality on the Aliases, Definitions and HyperLinks tabs, described in the topic standard tabs.
To create a new Simple Unit, select the Create Measurement Unit icon or in the context menu select Create a Simple Unit. On the Basic tab, provide the mandatory fields for Name and Short Name. Furthermore, it is required to provide the Container RDL, see the management and usage of RDLs.
After providing further details, click Ok to create the Simple Measurement Unit.
The required fields for the other types of measurement units:
On the Unit Factors tab, select all applicable Measurement Units together with their Exponent for the combination of measurement units.
On the Basic tab, first select the Container RDL
From all the items in this RDL, select a Prefix and applicable Reference Unit
The Name and Short Name are generated automatically as a combination from the selected prefix and unit.
Linear Conversion Unit
On the Basic tab, provide a Name, Short Name, and select the required Container RDL
Select the appropriate Reference Unit and Conversion Factor.
To edit a measurement unit, select the Edit Measurement Unit icon or in the context menu select Edit. Depending on the type of measurement unit, it is possible to edit all the available fields on the Basic or content-specific tabs, as well as optional items on the other tabs for Aliases, Definitions, and Hyperlinks.
After making the required changes, click Ok.
Please note that editing measurement units should be handled with extreme care, as this will have a large impact on all engineering models that use concepts that depend on it. It is advisable to only edit measurement units to fix apparent mistakes.
The browsers in the CDP™ Client of the user that performed the editing action will be updated immediately. Other CDP™ Clients will be updated with a [refresh][Refresh].
On the Advanced tab, a Revision Number is given; see the description of Revision Number for details.
To inspect a measurement unit, select the Inspect Measurement Unit icon or in the context menu select Inspect. In the Inspect modal dialog, all the details can be seen on the Basic or content-specific tabs, as well as optional tabs for Aliases, Definitions, and Hyperlinks. Additionally the status of the measurement unit is given by the check box for Deprecated, see the description of Delete below.
The Advanced tab provides information that may be useful mostly to CDP™ database administrators. Given are the UniqueID and the Revision Number.
A measurement unit should not be deleted from the CDP™.
To delete a measurement unit, select the Delete Measurement Unit icon or in the context menu select Delete. Items from the CDP™ are never completely deleted, but they are marked as Deprecated. This Deprecated status is an indication to users that it should not be used anymore.
To export measurement units, select the Export Measurement Units icon or in the context menu select Export.
Last modified 1 year ago.