IEC 61987-12-2016 pdf download.Industrial-process measurement and control – Data structures and elements in process equipment catalogues – Part 12: Lists of properties (LOPs) for flow measuring equipment for electronic data exchange.
4 General
4.1 Overview The LOPs provided by this document are intended for use in electronic data exchange processes performed between any two computer systems. The computer systems can both belong to the same company or they can belong to different companies as described in Annex C of IEC 61 987-1 0:2009. The OLOP for the family of flow measuring equipment is to be found in Annex A while the DLOPs of the individual flow device types are to be found in Annex B. Structural elements such as LOP type, block and property defined in this standard are available in electronic form in the “Automation equipment” domain of the IEC Common Data Dictionary (CDD).
4.2 Depiction of OLOPs and DLOPs
4.2.1 General The properties of the OLOPs and DLOPs used in this part of IEC 61 987 have been created in conformance to the requirements of the IEC 61 360 series. As such, the structural elements, properties and attributes to be found in the IEC Common Data Dictionary are normative.
4.2.2 Structural roles The entities within a list of properties can have one of a number of structural roles. a) Property A property exists as a property only. b) Ref. property + Block A reference property connects a block to the superordinate block or LOP in which it is embedded. Properties and sub-blocks listed below a block name and placed one position to the right are elements of the block. A block ends when another block name appears in the same column as the block name or in any other column to its left. The reference property has the same preferred name as the block to which it refers. All attributes of these properties are available in the IEC Common Data Dictionary (CDD). c) Cardinality property A cardinality property is connected to the block which immediately follows it. The value of the property (0 … n) in a transaction file determines the number of times the associated block shall be repeated. It is identified by the identifier in the column “Property identifier”. The preferred name of a cardinality property is “Number of <xxxx>“, where <xxxx> is derived from name of the block with which it is associated. In the transaction file (see examples in 4.3), it can be seen that a block has been repeated twice:
– the cardinality property directly before the block has a value greater than 1 ,
– the name of the repeated block is extended by “_” followed by the repetition number.IEC 61987-12 pdf download.