1、Representation of process control engineering Requestsin P 35.240.50Compliance with a British Standard cannot confer immunity fromlegal obligations.This British Standard was published under the authority of the StandardsPolicy and Strategy Committee on 31 May 2010.Amendments issued since publication
2、Amd. No. Date Text affectedBRITISH STANDARDBS EN 62424:2009EUROPEAN STANDARD EN 62424 NORME EUROPENNE EUROPISCHE NORM August 2009 CENELEC European Committee for Electrotechnical Standardization Comit Europen de Normalisation Electrotechnique Europisches Komitee fr Elektrotechnische Normung Central S
3、ecretariat: Avenue Marnix 17, B - 1000 Brussels 2009 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members. Ref. No. EN 62424:2009 E ICS 35.240.50; 25.040.40 English version Representation of process control engineering - Requests in P it shall not
4、allow unguided automatic changes. The configurable checking step shall include functionality for automatic or manual acceptance of data changes, allowing single decisions up to bulk data management. All changes in the proprietary database and all discovered data inconsistencies shall be reported by
5、the import application. The generation of the report shall be configurable. The import/export application has to assure that the intersection of the different databases contains the same information, and that additional division specific data is handled in a consistent way. Data manipulation by a pr
6、oject division is an ongoing process during the whole project and beyond it. Thus the creation, changing and deletion of data shall be possible during the life-cycle of the plant. CAEX databases have to be consistent. This requires a consistency check before exporting the data. This procedure has to
7、 be followed after a successful data manipulation in a P 2) mandatory fields being filled in; 3) correct use of numbering system of the PCE requests. Inconsistent data shall not be exported. b) generate PCE relevant information; c) check for changed information in comparison with previously stored d
8、ata in the neutral database; d) renaming of PCE request shall be supported by the export functionality; e) perform data export from proprietary into neutral database: 1) e. g. if the PCE request has been changed, the old PCE request within the neutral database has to be deleted and the new one shall
9、 be exported from the proprietary database into the neutral database. The old PCE request information shall be stored in a backup storage system; 2) Other changes shall be performed with the existing object. f) generate reports after each data exchange: e. g. new PCE requests list, missing PCE reque
10、sts list, changed PCE requests list, deleted PCE requests list, problems and error list. Data import from neutral database into the target database shall comprise the following activities: g) generate PCE relevant information from neutral database; h) check for changed information by comparing the n
11、eutral database with the target database; i) perform data import from the neutral into the proprietary database; j) renaming of PCE request shall be supported by the import functionality; k) generate reports after each data exchange: 1) e. g. error lists; 2) inconsistencies due to imported data shal
12、l be detected by the target application during the import process and are not considered within this standard. 6 Representation of PCE requests in a P b) the graphical representation of PCE requests in a P c) the type of functional connection between the PCE requests: the control functions; d) the g
13、raphical representation of signals in a P&ID. In addition the reference designation scheme used for PCE requests in a P&ID shall be specified. Detailed information on complex control functions shall not be part of the P&ID. Therefore, additional documentation (e.g. control narratives, function chart
14、s) has to be prepared to define the required functionality. A control function shall also be individually identified and shall be represented on the P&ID. 6.3 Requirements for the identification and representation of PCE requests 6.3.1 General Each PCE request shall be graphically represented by a b
15、ubble, which collects all information about the functional requirements. Three data fields inside and ten data fields outside the bubble are defined to hold all the information of a PCE request (see Figure 3). For detailed information see 6.3.3 to 6.3.9. USxxxx.3AH SHH AH SHH YS xxxx.4 AL OH PCE loo
16、p xxxx (optional) PCE request PCE control function aPCE request FIxxxx.2 TIxxxx.1 PCE request BS EN 62424:2009 18 62424 IEC:2008(E) Figure 3 General representation of a PCE-Request in a P&ID As stated before, only the PCE functionality shall be depicted on the P&ID, not the PCE implementation. In ex
17、ceptional cases however, there might be constellations where the presentation of detailed realization information is inevitable. For example, in the case of a multi-sensor element which means an instrument that produces measurements for different categories, every category shall be represented by it
18、s own bubble. The bubbles are stacked up, as shown in Figure 4. Figure 4 Multi-sensor element In all cases where the PCE request is connected to the equipment or pipe, this shall be shown by a full line, connecting the bubble with the equipment or pipe. 6.3.2 Types of lines Signal lines are used to
19、illustrate the functional relationship between PCE requests. A signal line shall be depicted as a dashed line with an arrow to indicate the information flow. Source of information flow shall be a bubble of a PCE control function or request or switching action consisting of the six fields right outsi
20、de the bubble. The sink of information flow shall be a bubble of a PCE request or a control function. Process connections shall be depicted by a solid line without a direction. Multi-sensor instruments with only one process connection shall have an extra bubble for each category and only one process
21、 connection. 6.3.3 Displaying the location of the operator interface Each PCE request is graphically represented by a bubble. This standard distinguishes the location of the operator interface between a local interface, a local control panel and a central control room. The location does not reflect
22、any realization in systems. A local interface shall be represented as shown in Figure 5. It could be e. g. a pressure gauge. PCE category and functionPCE IdentificationPU Vendor Typical ident. Device information ZHHHAHSHHALALLSLLLSafety relevant GMPQuality relevant (SIL3)DIxxxxFIxxxxPIxxxxBS EN 6242
23、4:200962424 IEC:2008(E) 19 PIxxxxFigure 5 Local interface Operator action/information on a local control panel shall be represented as shown in Figure 6. HSxxxxFigure 6 Manually operated switch in local control panel Remote requests operated in a central control room shall be represented as shown in
24、 Figure 7. PIxxxxFigure 7 Pressure indication in central control room 6.3.4 PCE categories and processing functions 6.3.4.1 Indication of PCE categories and processing functions The upper part of the bubble shall show the information of the PCE category and its PCE processing function. Each bubble s
25、hall have at least one PCE category and one PCE processing function. As exception for the processing function see 6.3.4.3. 6.3.4.2 PCE categories The first letter represents the PCE request and shall be selected from Table 2 if the measuring or initiating variable is listed in that Table. If this is
26、 not the case, a new category may be defined. A unique definition is recommended to provide for an automatic transfer to the specific equipment specification for the process control engineer. In case of amendments of categories of Table 2, a coding via letter X as described in table footnote b may b
27、e used. Modifying letters for the PCE category shall not be used to avoid misinterpretation in the course of automatic transfer to the specific equipment specification for the process control engineer. BS EN 62424:2009 20 62424 IEC:2008(E) Table 2 PCE categories Letter PCE category A Analysis B Burn
28、er or combustion C a D Density E Voltage F Flow G Distance, length, position H Hand or manual and manually initiated operation I Current J Power K Time based function L Level M Moisture or humidity N Actuation setting (motor) cO a P Pressure Q Quantity or counter R Radiation S Speed or frequency T T
29、emperature U N.A. (see 6.3.10) V Vibration or mechanical analysis W Weight, mass, force X b Y Actuation setting (valve) cZ a aThe definition of this letter should be defined by users. bThe unclassified letter X is intended to cover unlisted meanings that will be used only once or used to a limited e
30、xtent. If used, the letter may have any number of meanings as a PCE category and any number of meanings as a PCE function. cThe use of N for motor driven actuators and Y for valve actuators is based on different PCE activities and maintenance requirements for both types of actuators. Moreover, in th
31、e light of increased maintenance requirements in the plant, immediate identification for transferring of data and relevant attributes of the actuator to asset management systems is necessary. 6.3.4.3 PCE processing functions Starting with the second character, the successive letters in the upper par
32、t of the bubble shall represent the processing function of the PCE request. The letters given in Table 3 shall be used to indicate the processing function of a PCE request. BS EN 62424:200962424 IEC:2008(E) 21 Table 3 PCE processing function Letter Processing function A Alarm, message B Restriction
33、C Control D Difference E N.A . F Ratio G N.A. H High limit, on, opened I Indication of analogue values J N.A. K N.A. L Low limit, off, closed M N.A. N N.A. O Local or PCS status indication of binary signals P N.A. Q Integrating or counting R Recorded value S Binary control function or switching func
34、tion (not safety relevant) T N.A. U N.A. V N.A. W N.A. X b Y Computing function Z aBinary control function or switching function (safety relevant) aThe triangle may also be used to indicate in a redundant way that the processing function is safety relevant (see Figure 3). bThe unclassified letter X
35、is intended to cover unlisted meanings that will be used only once or used to a limited extent. If used, the letter may have any number of meanings as a PCE category and any number of meanings as a PCE function. The letters I and R refer to the result of the preceding processing function, e. g. FIQI
36、 means the indication of a flow and its quantity. The PCE processing functions A, H, L, O, S and Z shall only be used outside the bubble. In this case the PCE category may stand as a single value in the upper part of the bubble. In addition, a detailed definition for the signal information (see 6.3.
37、2) to be transferred automatically to the control equipment specification for the process control engineer is given by this way. The combination of processing functions shall be used in the sequence given in Table 4. The table hierarchy shall be from left to right and per column top down. BS EN 6242
38、4:2009 22 62424 IEC:2008(E) Table 4 Sequence combinations Category Sequence 1 2 3 4 See Table 3 1 F D Y C 2 B Q X - 6.3.4.4 PCE processing functions for actuators The PCE processing functions shall be used for actuators in the same way as for sensors. Some examples are shown in Table 5. Table 5 PCE
39、processing functions for actuators Letter Processing function YS On/off valve YC Control valve YCS Control valve with on/off function YZ On/off valve (safety relevant) YIC Control valve continuous position indication NS On/off motor NC Control motor The valve operating mechanism, e. g. electric, pne
40、umatic or hydraulic, is not specified by its presentation in the bubble in the P&ID. Graphical representation of the equipment valve including further functional details in the equipment symbols in accordance to ISO 10628 in the P&ID cannot be used in the CAEX model. Such details shall be placed in
41、the database. 6.3.5 PCE request reference designation scheme A reference designation scheme (e. g. IEC 61346-1) shall be used in order to identify the PCE request unambiguously. This identification shall be independent of the PCE processing function of the PCE request and depicted in the lower part
42、of the bubble. Preceding identification levels (e. g. site, plant, unit, area) may be omitted in the bubble if the request within the context of the P&ID is unique (see Figure 8). If PCE requests are combined in a PCE loop, their identification shall have separated levels for the loop and the reques
43、t. BS EN 62424:200962424 IEC:2008(E) 23 XXXXNSUnit: uuuuArea: aaaaPlant: ppppMNOTE In the bubble of the depicted request only the last level of the identification system is shown. The plant, area and unit information can be taken from the lower left corner. Thus the complete identification of the re
44、quest is: pppp-aaaa-uuuu-xxxx. Figure 8 Example of PCE request identification 6.3.6 PU-vendor and typical identification If applicable, PU vendor information shall be given above the horizontal line, but outside the bubble on its upper left side, as shown in Figure 9. If this field is not used for P
45、U vendor information, it may be used to show other project specific information. Figure 9 Example of flow measurement with indication in the CCR delivered by vendor A specified by typical A20 To support automatic loop, request and tag generation with PCE CAE tool requests, especially motor requests
46、should be indicated by a “typical” number on the upper left side, outside the bubble. These “typicals” are fixed by the project-team and are used to determine the composition of the PCE request, e. g. how the motor drive should be switched (with start-stop only, with start-stop and running indicatio
47、n, with current measurement, etc.) or a combination of measuring systems. 6.3.7 Device information If, because of the PCE category, additional device information is needed (e.g. orifice for flow measurement), this shall be indicated in the lower zone outside the bubble on the left side (see Figure 1
48、0). AIxxxxpHFigure 10 Example of pH-measurement with indication in the CCR A20xxxxFIVendor ABS EN 62424:2009 24 62424 IEC:2008(E) 6.3.8 Alarming, switching and indicating The characters H and L as PCE processing functions, indicating the high or low limit, shall be used in combination with A, O, S o
49、r Z only if an automatic action (S or Z), an operator action (A) or an indication (O) is activated when the limits are reached. In each level (e. g. H, HH, HHH) it shall be possible to combine alarming and switching function, e.g. AS or AZ. These functions shall always be indicated outside the bubble, as shown in Figure 11. Up to three levels for high and also for low alarm/switching/indication shall be possible. Figure 11 Example of flow measurement with indication in the CCR and high and low alarm Th