How do Instruments & Controls fit in?

latest update: 2018-12-22    

Introduction

This topic is about instrumentation and controls, and in particular how these are being represented in the RDL.

Description

All Instrumentation & Controls classes are, in the top of their class hierarchies, strictly separated by function. In the table below this is shown for the first level in the hierarchy:

  

SUPERCLASS(ES)

 

CLASS NAME

NAMESPACE+ID

DEFINITION

ISO 15926-2 ENTITY TYPE

FunctionalObject         INSTRUMENTATION FUNCTION

rdl:RDS2225050

An <INSTRUMENTATION FUNCTION> is a <FunctionalObject> that is capable of one or more of the following activities: <ACTUATING>, <COMPUTING>, <CONTROLLING>, <DETECTING>, <INDICATING>, <MEASURING>, <MONITORING>, <PROTECTING>, <RECORDING>, <REGULATING>, <SIGNAL AMPLIFYING>, <SIGNAL CONVERTING>, <SIGNAL CONVEYING>, <SWITCHING>, <TRANSDUCING>, <TRANSMITTING>, and <WARNING> related to physical variables (quantities).

dm:ClassOfFunctionalObject

ARTEFACT

INSTRUMENTATION FUNCTION

     

INSTRUMENTATION ITEM

rdl:RDS2220012

An <INSTRUMENTATION ITEM> is an <ARTEFACT> and a <INSTRUMENTATION FUNCTION>.

dm:ClassOfInanimatePhysicalObject

INSTRUMENTATION FUNCTION

       

BOOLEAN LOGIC FUNCTION

rdl:RDS222482

A <BOOLEAN LOGIC FUNCTION> is an <INSTRUMENTATION FUNCTION> that is capable of <EXECUTING> Boolean logic.

dm:ClassOfFunctionalObject

INSTRUMENTATION FUNCTION

       

CONTROLLER

rdl:RDS289844

A <CONTROLLER> is an <INSTRUMENTATION FUNCTION> that is capable of <CONTROLLING>.

dm:ClassOfFunctionalObject

INSTRUMENTATION FUNCTION

       

FINAL CONTROL FUNCTION

rdl:RDS2220650

A <FINAL CONTROL FUNCTION> is an <INSTRUMENTATION FUNCTION> that physically changes a process in response to a change in the output from a <CONTROLLER>.

dm:ClassOfFunctionalObject

INSTRUMENTATION FUNCTION

       

INDICATOR

rdl:RDS418499

An <INDICATOR> is an <INSTRUMENTATION FUNCTION> that has a capability of <INDICATING>.

dm:ClassOfFunctionalObject

INSTRUMENTATION FUNCTION

SIGNAL CIRCUIT

SYSTEM    

INSTRUMENT LOOP

rdl:RDS222493

An <INSTRUMENT LOOP> is an <INSTRUMENTATION FUNCTION> and a <SIGNAL CIRCUIT> and a <SYSTEM> that has two or more interlinked <INSTRUMENTATION FUNCTION>s.

dm:ClassOfFunctionalObject

INSTRUMENTATION FUNCTION

SIGNAL CIRCUIT ELEMENT

     

INSTRUMENT LOOP ELEMENT

rdl:RDS222220

An <INSTRUMENT LOOP ELEMENT> is a <INSTRUMENTATION FUNCTION> and a <SIGNAL CIRCUIT ELEMENT> capable of operating as a part in an <INSTRUMENT LOOP>.

dm:ClassOfFunctionalObject

INSTRUMENTATION FUNCTION

SYSTEM

     

INSTRUMENTATION SYSTEM

rdl:RDS222491

An <INSTRUMENTATION SYSTEM> is a <INSTRUMENTATION FUNCTION> and a <SYSTEM>

dm:ClassOfFunctionalObject

INSTRUMENTATION FUNCTION

       

MEASURING FUNCTION

rdl:RDS1415826371

A <MEASURING FUNCTION> is an <INSTRUMENTATION FUNCTION> that is capable of <MEASURING>.

dm:ClassOfFunctionalObject

INSTRUMENTATION FUNCTION

       

MONITOR

rdl:RDS13175715

A <MONITOR> is an <INSTRUMENTATION FUNCTION> that is capable of <MONITORING>.

dm:ClassOfFunctionalObject

INSTRUMENTATION FUNCTION

GAUGE

     

PROCESS GAUGE

rdl:RDS462644

A <PROCESS GAUGE> is a <INSTRUMENTATION FUNCTION> and a <GAUGE> that is a stand-alone device for measuring or sighting a process variable.

dm:ClassOfFunctionalObject

INSTRUMENTATION FUNCTION

       

PROCESS SIGNAL GENERATING FUNCTION

rdl:RDS2220983

A <PROCESS SIGNAL GENERATING FUNCTION> is an <INSTRUMENTATION FUNCTION> that generates a <SIGNAL> that represents the magnitude of a process variable.

dm:ClassOfFunctionalObject

INSTRUMENTATION FUNCTION

       

READER

rdl:RDS2224301

A <READER> is an <INSTRUMENTATION FUNCTION> that has the capability of <READING> some <CODE>.

dm:ClassOfFunctionalObject

INSTRUMENTATION FUNCTION

       

RECORDER

rdl:RDS282059

A <RECORDER> is an <INSTRUMENTATION FUNCTION> that is capable of <RECORDING>.

dm:ClassOfFunctionalObject

INSTRUMENTATION FUNCTION

VALVE

     

SELF-OPERATING VALVE

rdl:RDS7018938

A <SELF-OPERATING VALVE> is an <INSTRUMENTATION FUNCTION> and a <VALVE> that includes a means of operation (e.g. spring / gravity / fluid pressure / counter balance), and is not depending on an external source of energy.

dm:ClassOfFunctionalObject

INSTRUMENTATION FUNCTION

CONVEYOR

     

SIGNAL CONVEYOR

rdl:RDS222448

A <SIGNAL CONVEYOR> is an <INSTRUMENTATION FUNCTION> and a <CONVEYOR> for a <SIGNAL>.

dm:ClassOfFunctionalObject

INSTRUMENTATION FUNCTION

SIGNAL RECEIVER

     

STANDARD SIGNAL RECEIVER

rdl:RDS222805

A <STANDARD SIGNAL RECEIVER> is a <INSTRUMENTATION FUNCTION> and a <SIGNAL RECEIVER> that is capable of <RECEIVING> a <STANDARD SIGNAL>.

dm:ClassOfFunctionalObject

INSTRUMENTATION FUNCTION

SIGNAL SENDER

     

STANDARD SIGNAL SENDER

rdl:RDS2223258

A <STANDARD SIGNAL SENDER> is a <INSTRUMENTATION FUNCTION> and a <SIGNAL SENDER> that is capable of <SENDING> a <STANDARD SIGNAL>.

dm:ClassOfFunctionalObject

INSTRUMENTATION FUNCTION

WARNER

     

STATE WARNER

rdl:RDS2220118

A <STATE WARNER> is an <INSTRUMENTATION FUNCTION> and a <WARNER> of an unwanted state change.

dm:ClassOfFunctionalObject

 

Click here for a report showing all 738 subclasses of INSTRUMENTATION FUNCTION.

No combinatory explosion

Since most instrumentation items and all controls are combinations of above functions the number of possible combinations is unmanageable. And they are not required either, because these combinations can be made on-the-fly in a kind of "cafetaria mode", similar to composing your food by selecting food from a counter.

An integrated measuring element of a transmitter, process switch, process gauge, or process-connected recorder gets a subtag (see B14-FT-101-E below) and is related to that instrument with an AssemblyOfAnIndividual template.

Combinations of functions are done by typing with the applicable functions (see B14-FRC-101 below, typed with RECORDER and CONTROLLER).

Using templates allows for a different choice of for a further specialization at a later time.  Just deprecate the old template and create a new one, whilst maintaining the old template for an audit trail.

Below three examples are given:

  1. A Flow Element B14-FE-101
  2. A Flow Transmitter B14-FT-101 with integral Orifice Plate B14-FT-101-E
  3. A Flow Recording Controller B14-FRC-101

# Declaration of Flow Element B14-FE-101

 

:09DABE733CC44800A5284CC64B5DA44D rdf:type dm:InanimatePhysicalObject, lci:NonActualIndividual, dm:WholeLifeIndividual, rdl:RDS461834 ; # FLOW MEASURING ELEMENT

    rdfs:label "B14-FE-101" ;

    meta:hasLifecycleActivity rdl:RDS2229995 ; # PLANT DESIGN

    meta:valEffectiveDate "2013-02-08T16:19:00Z"^^xsd:dateTime .

 

# Declaration of Flow Transmitter B14-FT-101 with internal

 

:D0901B525F2642B2B0912BDD017F300E rdf:type dm:InanimatePhysicalObject, lci:NonActualIndividual, dm:WholeLifeIndividual, rdl:RDS880154 ; # FLOW TRANSMITTER

    rdfs:label "B14-FT-101" ;

    meta:hasLifecycleActivity rdl:RDS2229995 ; # PLANT DESIGN

    meta:valEffectiveDate "2013-02-08T16:19:00Z"^^xsd:dateTime .

 

:7981FBFDFB764F4EBBECB392593C7D52 rdf:type dm:InanimatePhysicalObject, lci:NonActualIndividual, dm:WholeLifeIndividual, rdl:RDS5770524 ; # DIFF.PRESSURE MEASURING ELEMENT

    rdfs:label "B14-FT-101-E" ;

    meta:hasLifecycleActivity rdl:RDS2229995 ; # PLANT DESIGN

    meta:valEffectiveDate "2013-02-08T16:19:00Z"^^xsd:dateTime .

 

:39E421682CC0411DB0A75F945774BC0B rdf:type tpl:AssemblyOfAnIndividual ; # the Differential Pressure Measuring Element (below) is a part of the Flow Transmitter

    tpl:hasWhole :D0901B525F2642B2B0912BDD017F300E ;

    tpl:hasPart :7981FBFDFB764F4EBBECB392593C7D52 ;

    meta:hasLifecycleActivity rdl:RDS2229995 ; # PLANT DESIGN

    meta:valEffectiveDate "2013-02-08T16:19:00Z"^^xsd:dateTime . 

 

# Declaration of Flow Recording Controller B14-FRC-101

  

:16FD589AF5344B6BB4F45F2540E17AED rdf:type dm:InanimatePhysicalObject, lci:NonActualIndividual, dm:WholeLifeIndividual, rdl:RDS222472, rdl:RDS289844 ; # STANDARD SIGNAL RECORDER & CONTROLLER

    rdfs:label "B14-FRC-101" ;

    meta:hasLifecycleActivity rdl:RDS2229995 ; # PLANT DESIGN

    meta:valEffectiveDate "2013-02-08T16:19:00Z"^^xsd:dateTime .

 

 

Possible Worlds

In ISO 15926 the concept of Possible Worlds has been adopted, for the most Actual World vs Design World, in the code defined as ActualIndividual vs NonActualIndividual.

The only relation between a PhysicalObject in a Design World and a PhysicalObject in the Actual World is by using the Counterpart relationship. The only information implied with that relationship is that the object in the Actual World has been installed in the designed function. Not that that function is 100% fulfilled. That is put on record by classifying that PhysicalObject in the Actual World with the designed Requirements Class that is also clasifying the object in the Design World. This all is shown in an excerpt from the Plant Life-cycle Model below:

  

 

Designed PhysicalObject 17 is classified with a ClassOfFunctionalObject 14 that defines the functional aspects .

Designed PhysicalObject 17 is classified with a ClassOfPhysicalObject 21 that defines the physical and functional aspects (the latter by the subClassOf relation with the ClassOfFunctionalObject).

Actual PhysicalObject 55 is the Counterpart of designed PhysicalObject 17 in the Design World.

Actual PhysicalObject 53 is classified with ClassOfPhysicalObject 19 (defined on Specification 20) and 19 is also the Requirements Class for PhysicalObject 17.