Iec 61069 6 2016

The h man-mac ine interface fu ction are p rt of the s stem an ena le the o erator to monitor an manipulate the s stem itself, the external s stems an the proces.. In the as es ment of o

properties for the purpose of sy stem assessment –

Part 6: Assessment of sy stem operabi ity

des propriétés d'un sy stème en vue de son évaluation –

Partie 6: Évaluation de l opérabi ité d'un sy stème

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properties for the purpose of sy stem assessment –

Part 6: Assessment of sy stem operabi ity

des propriétés d'un sy stème en vue de son évaluation –

Partie 6: Évaluation de l opérabi ité d'un sy stème

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CONTENTS

FOREWORD 4

INTRODUCTION 6

1 Sco e 8

2 Normative referen es 8

3 Terms, definition , a breviated terms, acron ms, con ention an s mb ls 8

3.1 Terms an definition 8

3.2 Ab reviated terms, acron ms, con ention an s mb ls 8

4 Basis of as es ment sp cific to o era i ty 8

4.1 Op ra i ty pro erties 8

4.1.1 General 8

4.1.2 Ef icien y 10 4.1.3 Intuitivenes 10 4.1.4 Tran p ren y 1

4.1.5 Ro u tnes 1

4.2 Factors influen in o era i ty 12 5 As es ment method 12 5.1 General 12 5.2 Definin the o jective of the as es ment 12 5.3 Desig an layout of the as es ment 12 5.4 Plan in of the as es ment program 13 5.5 Exec tion of the as es ment 13 5.6 Re ortin of the as es ment 13 6 Evaluation tec niq es 14 6.1 General 14 6.2 Analytical evaluation tec niq es 15 6.2.1 General 15 6.2.2 Ef icien y 15 6.2.3 Intuitivenes 15 6.2.4 Tran p ren y 16 6.2.5 Ro u tnes 16 6.3 Empirical evaluation tec niq es 16 6.3.1 General 16 6.3.2 Ef icien y 16 6.3.3 Intuitivenes 16 6.3.4 Tran p ren y 17 6.3.5 Ro u tnes 17 6.4 Ad itional to ic for evaluation tec niq es 17 An ex A (informative) Checkl st an /or example of SRD for s stem o era i ty 18 A.1 General 18 A.2 Factors res ltin from the in u trial proces itself 18 A.3 Factors related with the task of the o erators, their freq en y, p rcentage of time sp nt, req ired n mb r of action , etc 19 A.4 Factors d e to the control strateg required 19 A.5 Factors con ernin the h man-mac ine interface desig 20 A.6 Influen e of the work lace on the o era i ty req irements 2

An ex B (informative) Checkl st an /or example of SSD for s stem o era i ty 2

B.1 SSD information 2

B.2 Check p ints for s stem o era i ty 2

An ex C (informative) Example of a l st of as es ment items (information from IEC TS 6 6 3-1) 2

C.1 Overview 2

C.2 Op ra i ty pro erties of Human Mac ine Interface (HMI) 23 C.2.1 General 2

C.2.2 Control ro m HMI hardware – s stem config ration 2

C.2.3 Control ro m HMI hardware – mac ines 2

C.2.4 Control ro m HMI hardware – monitors 2

C.2.5 Control ro m HMI hardware – sp cial display 2

C.2.6 Control ro m HMI sof ware 2

C.2.7 Req irements for L cal Op rator Interface 2

C.2.8 BPCS localsation 2

An ex D (informative) Phase of a s stem l fe c cle 2

Bibl ogra h 2

Fig re 1 – General layout of IEC 610 9 7

Fig re 2 – Op ra i ty 10 Ta le D.1 – Phases of a s stem lfe c cle 2

INTERNATIONAL ELECTROTECHNICAL COMMISSION

Part 6: Assessment of system operabi ity

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p te t rig ts IEC sh l n t b h ld resp nsible for id ntifyin a y or al su h p te t rig ts

International Stan ard IEC 610 9-6 has b en pre ared by s bcommit e 6 A: Sy tem

asp cts, of IEC tec nical commite 6 : In u trial-proces me s rement, control an

automation

This secon edition can els an re laces the first edition publ s ed in 19 8 This edition

con titutes a tec nical revision

This edition in lu es the fol owin sig ificant tec nical c an es with resp ct to the previou

edition:

a) re rganization of the material of IEC 610 9-6:19 8 to ma e the overal set of stan ard

more organized an con istent;

The text of this stan ard is b sed on the fol owin doc ments:

Ful information on the votin for the a proval of this stan ard can b fou d in the re ort on

votin in icated in the a ove ta le

This publcation has b en drafed in ac ordan e with the ISO/IEC Directives, Part 2

A l st of al p rts in the IEC 610 9 series, publ s ed u der the general title Industrialp roces

me sureme nt, co trol a d automato – Ev luato of system pro e rtes for th p u rp ose of

system as es me t, can b fou d on the IEC we site

The commit e has decided that the contents of this publcation wi remain u c an ed u ti

the sta i ty date in icated on the IEC we site u der "htp:/we store.iec.c " in the data

related to the sp cific publ cation At this date, the publ cation wi b

• reconfirmed,

• with rawn,

• re laced by a revised edition, or

• amen ed

IMPORTANT – Th 'colour in ide' logo on the cov r pa e of this publ c tion indic te

that it contain colours whic are consid re to be us ful for th cor e t

understa ding of its conte ts Us rs s ould therefore print this doc me t usin a

colour printer

IEC 610 9 de ls with the method whic s ould b u ed to as es s stem pro erties of a

b sic control s stem (BCS) IEC 610 9 con ists of the folowin p rts

Part 1: Terminolog an b sic con e ts

Part 2: As es ment methodolog

Part 3: As es ment of s stem fu ctional ty

Part 4: As es ment of s stem p rforman e

Part 5: As es ment of s stem de en a i ty

Part 6: As es ment of s stem o era i ty

Part 7: As es ment of s stem safety

Part 8: As es ment of other s stem pro erties

As es ment of a s stem is the jud ement, b sed on eviden e, of the s ita i ty of the s stem

for a sp cific mis ion or clas of mis ion

To o tain total eviden e would req ire complete evaluation ( or example u der al influen in

factors) of al s stem pro erties relevant to the sp cific mis ion or clas of mis ion

Sin e this is rarely practical, the rationale on whic an as es ment of a s stem s ould b

b sed is:

– the identification of the imp rtan e of e c of the relevant s stem pro erties;

– the plan in for evaluation of the relevant s stem pro erties with a cost ef ective

dedication of ef ort to the variou s stem pro erties

In con u tin an as es ment of a s stem, it is cru ial to b ar in min the ne d to gain a

maximum in re se in confiden e in the s ita i ty of a s stem within practical cost an time

con traints

An as es ment can only b car ied out if a mis ion has b en stated (or given), or if an

mis ion can b h p thesized In the a sen e of a mis ion, no as es ment can b made;

however, evaluation can sti b sp cified an car ied out for u e in as es ments p rformed

by others In s c cases, IEC 610 9 can b u ed as a g ide for plan in an evaluation an it

provides method for p rformin evaluation , sin e evaluation are an integral p rt of

as es ment

In pre arin the as es ment, it can b dis overed that the definition of the s stem is to

nar ow For example, a faci ty with two or more revision of the control s stems s arin

resources, for example a network, s ould con ider is ues of co-existen e an inter-o era i ty

In this case, the s stem to b in estigated s ould not b l mited to the “new” BCS; it s ould

in lu e b th That is, it s ould c an e the b u daries of the s stem to in lu e enou h of the

other s stem to ad res these con ern

The series stru ture an the relation hip amon the p rts of IEC 610 9 are s own in Fig re 1

Figure 1 – Ge eral la out of IEC 610 9

Some example as es ment items are integrated in An ex C

IEC

Part 1: T rmin logy an bas ic co ce t s

Part 2: As es me t met ho ology

Part s 3 t o 8: As ses sme t of each sy st em pro ert y

• Ge eric re uireme t of proce ure of as es me t

‐ Overview, ap roa h an p ases

‐ Re uireme t s for ea h p ase

‐ Ge eral d scrip o of ev luatio tech iq es

• Basics of as es me t sp cific to ea h pro ery

‐ Pro er ies an in u ncin factor

• As es me t meth d for ea h pro ery

• Ev luatio t ech iq esfor ea h pro ery

IEC 6 0 9: Indust ial-proces measurement , cont oland automation –

Evaluation of systemproper ies f or the purpose of systemas es ment

INDUSTRIAL-PROCESS MEASUREMENT, CONTROL AND AUTOMATION –

Part 6: Assessment of system operabi ity

This p rt of IEC 610 9:

– sp cifies the detai ed method of the as es ment of o era i ty of b sic control s stem

(BCS), b sed on the b sic con e ts of IEC 610 9-1 an methodolog of IEC 610 9-2;

– defines b sic categorization of o era i ty pro erties;

– des rib s the factors that influen e o era i ty an whic ne d to b ta en into ac ou t

when evaluatin o era i ty;

– provides g idan e in selectin tec niq es from a set of o tion (with referen es) for

evaluatin the o era i ty

The folowin doc ments, in whole or in p rt, are normatively referen ed in this doc ment an

are in isp n a le for its a pl cation For dated referen es, only the edition cited a pl es For

u dated referen es, the latest edition of the referen ed doc ment (in lu in an

amen ments) a pl es

IEC 610 9-1:2 16, Industrialproces me sureme t, co trol a d au tomato – Ev luato of

system p rop ertes for th p urp ose of system as e ssme t – Part 1: Termin lo y a d b asic

co cep ts

IEC 610 9-2:2 16, Industrialproce ss me sureme t, co trol a d au tomato – Ev luato of

system p rop ertes for th p urp se of system as es me t – Part 2: As es me t meth dolo y

3 Terms, definitions, abbreviated terms, acronyms, conventions and s mbols

3.1 Terms a d definitions

For the purp ses of this doc ment, the terms an definition given in IEC 610 9-1 a ply

3.2 Abbre iate terms, a ron ms, conv ntions a d s mbols

For the purp ses of this doc ment, the a breviated terms, acron ms, con ention an

s mb ls given in IEC 610 9-1 the fol owin a ply

4 Ba is of asse sment specific to opera i ity

4.1 Operabi ity propertie

4.1.1 Ge eral

For a s stem to b o era le the s stem provides the o erator with a tran p rent an

con istent win ow into the tasks to b p rformed, throu h its h man-mac ine interface The

intuitive, tran p rent an ro u t interaction can b expres ed by the o era i ty s stem

pro erty

The h man-mac ine interface fu ction are p rt of the s stem an ena le the o erator to

monitor an manipulate the s stem itself, the external s stems an the proces

The req irements for o era i ty are stron ly af ected by the ski an knowhow of the

p rson el o eratin the s stem

The degre of the o era i ty s stem pro erty varies de en in on the phases of the s stem

mis ion d rin its l fe c cle

Op ra i ty req irements can difer b twe n these phases of the l fe c cle of the s stem They

de en up n the tasks to b p rformed d rin the phase an the d ration of the phase

The o era i ty req irements can b hig where the d ration of a phase is s ort an its

relevan e for the s stem mis ion critical The req irements can b low where the d ration of

a phase is lon , so that seq en es of req ired action for certain o eration can b le rnt by

the o erator over the lon term the s stem is u ed

In the as es ment of o era i ty, one is con erned with the way whic information given by

the o erator to the s stem (s c as comman s an req ests), is proces ed by the s stem

Ad itional y, one is con erned with the tran p ren y of information comin from the s stem to

the o erator, s c as proces /s stem state an values, tren s, re orts, etc

Whi e sp cial o era i ty me s res are sometimes ne ded d rin the desig an /or

maintenan e phases of the s stem, the o era i ty req irements are mostly u dersto d as

those neces ary d rin the o erational phase of an in u trial proces plant

Al phases of l fe c cle of the s stem s ould b ta en into ac ou t for evaluation of s stem

o era i ty pro erties Durin e c phase the s stem wi typical y b o erated by a diferent

group of o erators, with diferent o era i ty req irements

In ad ition, plan ed, u plan ed an disturb d plant o eration mig t ne d diferent o eratin

s hemes an hen e o era i ty req irements

An ex D s ows the variou phases, the o erator(s) u in the s stem d rin these phases,

their typical tasks an the typ of interfaces uti zed

The p rce tion of the o era i ty s stem pro erty is stron ly afected by the p rforman e

s stem pro erty (esp cial y sp ed of resp n e) an the fu ctional ty s stem pro erty

Op ra i ty pro erties are categorized as s own in Fig re 2

Fig re 2 – Operabi ty

Op ra i ty can ot b as es ed directly an can ot b des rib d by a sin le pro erty

Op ra i ty can only b determined by analy is an testin of e c of the o era i ty

pro erties in ivid al y

Some asp cts can b q antified by analy in the ergonomic asp cts of the pro erties, an by

me s rin the n mb r of action an time req ired to ac ompl s a given task ( he eficien y

of the h man-mac ine interface), others can b q alfied in a des riptive way

Eficien y, intuitivenes , tran p ren y an ro u tnes e c can ot b q antified as a sin le

n mb r However they can b expres ed by a q al tative des ription containin some

q antified elements, s c as:

– a coverage factor, o tained by comp rin the o eratin me n provided by the s stem

with the sp cific req irements as stated in the s stem req irements doc ment;

– a plca le ergonomic stan ard ; an

– the time req ired to give a comman , an to req est information

4.1.2 Ef icie c

A s stem has o era i ty eficien y if it al ows the o erator, with a minimum risk of ma in

er ors, to p rform his task(s) with a minimum amou t of mental an ph sical efort within an

ac e ta le time frame

The extent to whic the o eratin me n provided by the s stem minimise o erator time an

ef ort req ired in u in the s stem to ac ompls his tasks within stated con traints is a

me s re of the o era i ty ef icien y of the s stem

The o era i ty ef icien y de en s, amon others, on the fol owin elements:

– the ergonomic desig of the devices (k yb ard, mou e, voice input, dedicated kno s,

s re n , in icators, etc.) u ed as o eratin me n in s p ort of the h man-mac ine

interface;

– the ge gra hical lay-out, the n mb r of these devices an their relative location on the

o erators’ work lace;

– the s a e of the o erators’ work lace;

– the lmitation imp sed by the o eratin en ironment an protective clothin (in o r,

outdo r, day, nig t, gog les, gloves, etc.);

– the method to b u ed to retrieve information, to is ue comman s, etc

4.1.3 Intuitiv ne s

Intuitivenes re resents the simpl city an in tant u derstan in the s stem provides, whic

ena les the o erators to give comman s an present information to the o erators

Ad itional y intuitivenes ta es into ac ou t the ski s, ed cational level an general c lture of

IEC

Op ra i ty

The degre to whic the o erational me n are con istent with common workin practices is

a me s re of the o era i ty intuitivenes of the s stem

The o era i ty intuitivenes de en s on the fol owin factors:

– the extent to whic stan ard generic rules an method for the o eration of “action” items

are fol owed;

– the con ention folowed to present information to the o erator, for example red for

emergen y con ition , etc

– the con ention fol owed to give comman s, for example turnin a kno clockwise to

in re se a value, etc

Unl k other o era i ty pro erties, intuitivenes is not a total y in erent pro erty of the

s stem Some of the intuitivenes can de en on the p rtic lar u er domain

This domain can b defined in terms of c lture, international an /or pro rietary stan ard , etc

4.1.4 Tra spare c

Tran p ren y re resents the a i ty, of the o eratin me n provided by the s stem, to

se min ly place the o erator in direct contact with his tasks This ena les the o erator to give

comman s an view information, returned from the s stem, with a re l stic view of the action

(an their seq en e)

The extent to whic these me n are provided is a me s re of the tran p ren y of the s stem

The tran p ren y de en s on the fol owin factors:

– the logical prin iples fol owed to present the fu ctional an ge gra hical stru ture of the

proces an the tasks to b p rformed by the o erator;

– the way in whic la els an names are u ed to identify the o eratin me n , an the

con isten y of their u e;

– the con isten y in the a plcation of colours, names, au ible sig als, etc throu hout al

tasks an levels of information;

– the way of the d namic of the tasks are re l stical y simulated, to give the o erator a

“re l” fe l of the task to b p rformed, etc

Tran p ren y in lu es that the information presented by the s stem is cle r, con ise,

u ambig ou , an non-contradictory Non self explanatory information can b explained by a

more detai ed des ription in e si y ac es ible doc mentation or a help fu ction for

tran p ren y

4.1.5 Ro ustne s

Ro u tnes in lu es that the o eratin me n provided by the s stem to ena le the o erator

to give comman s cor ectly interpret an resp n to an o erator action If the o eration

me n are ambig ou , ad itional information can b req ested by the s stem for removin

the ambig ities

Ro u tnes de en s on the fol owin factors:

– the extent to whic deviation from the stan ard generic rules is p rmited, an is

interpreted;

– the extent to whic the s stem is a le to detect an notify deviation an to couple these

deviation with req ests for further information, etc

4.2 Fa tors influe cing o erabi ity

The o era i ty pro erties of a s stem can b afected by the influen in factors l sted in

• the o era i ty of a s stem is in itself not influen ed by the a i ties of the p rson, who

o erates the s stem However, the req irements for the o era i ty are u ual y b sed

on an imaginary o erator havin the statistical me n values of the q al fication , s c

as ski an knowhow, of the p rson el o eratin the s stem Deviation from these

me n values can influen e e c of o era i ty pro erties

• temp rature, EMC, agein , mou tin , cor osive s bstan es, an d st

The o era i ty also de en s, on other influen in factors:

– proced res for ac es to an entry of information an data into the s stem;

– the extent of information o tained by a sin le req est;

– information formats u ed;

– interface devices u ed (e.g tou h cre n, l g t p n, k yb ard)

Definin s o e of as es ment s al fol ow the method laid down in IEC 610 9-2:2 16, 5.3.1

Colation of doc mented information s al b con u ted in ac ordan e with IEC 610 9-2:2 16,

5.3.3

The statements compi ed in ac ordan e with IEC 610 9-2:2 16, 5.3.3 s ould in lu e the

– the o era i ty pro erties req ired for e c of the tasks an for the s stem, ar an ed in

order of the relevant phase or phases of the s stem l fe c cle;

– the knowhow, exp rien e an ski of the o erators u in the interface to p rform e c of

the tasks defined in the SRD;

– the n mb r of e.g information sources, sen ors an their as ociation with tasks whic

req ire o erators to u e the h man-mac ine interface simultane u ly

De en in on the phase of the s stem l fe c cle, as es ment of o era i ty can only b done

with existin or simi ar s stems in o eration These as es ments s ould in lu e the prior

knowled e, ski an exp rien e of the s stem desig er, the plant s if s pervisors, the

s stem maintenan e p rson el, etc

Doc mentin col ated information s al fol ow the method in IEC 610 9-2:2 16, 5.3.4

Selectin as es ment items s al fol ow IEC 610 9-2:2 16, 5.3.5

As es ment sp cification s ould b develo ed in ac ordan e with IEC 610 9-2:2 16, 5.3.6

Comp rison of the SRD an the SSD s al fol ow IEC 610 9-2:2 16, 5.3

NOT 1 A c e klst of SR for system d p n a i ty is pro id d in An e A

NOT 2 A c e klst of S D for system d p n a i ty is pro id d in An e B

5.4 Pla nin of the a s s me t program

The p rce tion of the o era i ty s stem pro erty can also b sen itive to internal s stem

factors related to the fu ctional ty an p rforman e pro erties, esp cial y time resp n e an

update freq en y

The evaluation of the o era i ty s stem pro erty s ould therefore alway b preceded by an

evaluation of the fu ctional ty an p rforman e pro erties, u les res lts are avai a le from

e rl er evaluation

Plan in of the as es ment program s al fol ow the method as laid down IEC 610 9-2:2 16,

5.4

As es ment activities s al b develo ed in ac ordan e with IEC 610 9-2:2 16, 5.4.2

The final as es ment program s ould sp cify p ints sp cified in IEC 610 9-2:2 16, 5.4.3

5.5 Ex c tion of th a s s me t

The exec tion of the as es ment s al b in ac ordan e with IEC 610 9-2:2 16, 5.5

5.6 Reportin of th a s s me t

The re ortin of the as es ment s al b in ac ordan e with IEC 610 9-2:2 16, 5.6

The re ort s al in lu e information sp cified in IEC 610 9-2:2 16, 5.6 Ad itional y, the

as es ment re ort s ould ad res the fol owin p ints:

– No ad itional items are noted

6 Ev luation tec niques

Within this stan ard, several evaluation tec niq es are s g ested Other method may b

a pl ed but, in al cases, the as es ment re ort s ould provide referen es to doc ments

des ribin the tec niq es u ed

Those evaluation tec niq es are categorized as des rib d in IEC 610 9-2:2 16, Clau e 6

The tec niq es given in 6.2, 6.3 an 6.4 are recommen ed to as es o era i ty

It is not p s ible to evaluate the o era i ty s stem pro erty as one entity In te d o era i ty

s stem pro erty s ould b ad res ed se arately

a) Satisfaction as a me s re of o era i ty

Satisfaction can b a me s re of o era i ty, an is the s bjective impres ion of o erators of

the o era i ty of the s stem or in other word it is a me s re of the ac e ta i ty by the

o erators of the h man-interface However, it s ould b noted that me s res of satisfaction

wi des rib the comfort an ac e ta i ty of the whole s stem to the o erator an are not

restricted to the o era i ty s stem pro erty alone Satisfaction can only b determined

q al tatively by q estionin a re resentative sample of o erators, an sometimes b

q antified statistical y u in an atitu e ratin s ale d rin the s stem o erational lfe time by

evaluatin the n mb r of p sitive or negative comments o tained d rin its u e

The level of ac e ta i ty of o era i ty of the s stem by o erators de en s up n the folowin

p ints:

– how the req ests an action to the s stem can b p rformed by the o erators;

– how the information given by the s stem, in resp n e to the req est an action , can

b recog ized by the o erators;

– how the information an their proces in by the s stem is coherent an logical an

how they conform to the exp ctation of the o erators;

– how the level of p sitive stres to the mental an ph sical a i ties of the o erator is

in u ed by the s stem

The q estion , directed to the o erator group selected for the evaluation to o tain a me s re

of satisfaction, s ould therefore b careful y worded an only b related to the o era i ty

asp cts of the s stem

Me s res of satisfaction can provide a u eful in ication of the o erators’ p rce tion of

o era i ty, even if it is not p s ible to o tain me s res of efectivenes or ef icien y

b) Con ideration of q al fication of o erators

The o jective of as es ment is to as es o era i ty as a s stem pro erty an not the

q al fication of the o erator to p rform a task, nevertheles their q al fication s ould b

ta en into ac ou t when desig in the as es ment

The q al fication of the o erators are formed an af ected by the fol owin a i ties an

asp cts:

– ph sical a i ties s c as the sen itivity of the eye (o tical sig als, colour bl n nes ,

heig ts of let ers an s mb ls, etc.), sen itivity of the e r (acou tical sig als, ran e of

au ibi ty), dimen ion of han s, fe t, h man stature (mec anical action , dimen ion

of kno s, etc.), etc

– ps c ological asp cts s c as temp rament, c aracter, c ltural an eth ic b ckgrou d,

heritage, etc but also exp ctation , etc

The group of o erators selected for the as es ment of satisfaction s ould therefore b

c osen careful y an in ac ordan e with the o eratin phase for whic the h man-mac ine

Al tasks s ould b examined in ivid al y an col ectively to c eck whether the h man

-mac ine interface u es me s res an method in ac ordan e with existin stan ard an the

req irements

6.2.2 Ef icie c

To analytical y evaluate the eficien y of o era i ty, time an efort s al b determined

An estimation of the time to fulfi e c task is made by:

– s bdividin e c of the tasks or clas es of tasks into action an /or ste s,

– cou tin the n mb r of ste s,

– uti zin known times for e c ste (If ste times are not known, them as umin e c ste

req ires a proximately the same time may b uti zed), an

– multiplyin time an ste s, to yield the total time

An estimation of the efort to fulfi e c task is made by:

– s bdividin e c of the tasks or clas es of tasks into action an /or ste s,

– comp rin the lay out (p sition, relative p sition, order, etc.),

– comp rin ph sical dimen ion (of the layout, buton sizes, etc.),

– uti zin ergonomic stan ard s c as ISO 9 41-10 [7]

To analytical y evaluate intuitivenes , the s stem interface solution s ould b careful y

comp red with the s stem req irements doc ment an the degre of cor esp n en e

_ _ _ _ _

q antified Unles the analy is is fol owed by an empirical evaluation the data o tained are

s bjective

6.2.4 Tra spare c

It s ould b c eck d that the o erator’s action an cor esp n in s stem re ction an

presentation are related to the task in a cog itive man er This me n that p p rwork or

exten ive mental proces es are not req ired, to con ert the h man u derstan in of the task

into its s stem re resentation

6.2.5 Robustne s

The doc mented fu ction (hardware an /or sofware) provided in the s stem to en ure

ro u tnes s ould b analy ed to c eck whether these cover for example:

– a method to acknowled e the receipt of information d rin tran fer of data b twe n

mod les;

– the a i ty to detect er ors cau ed by external noise an /or false or u authorised

information;

– the a pl cation of red n an y, for example retran mis ion, c cle red n an y c eck;

– the in lu ion of a re sona i ty c eck, etc

6.3 Empiric l e aluation te hniq e

6.3.1 Ge eral

The empirical evaluation s ould alway b preceded by an analytical evaluation

For the empirical evaluation a s stem model s ould b as embled This s ould comprise a

selection of s stem fu ction , closely re resentin the tasks to b p rformed an the two-way

commu ication me n of the h man-mac ine interface

6.3.2 Ef icie c

The p rforman e of a selection of task(s), by a group of typical o erators, s ould b

monitored

The seq en e of ste s actual y ta en by e c o erator s ould b recorded together with the

total o erator time (but ex lu in s stem fu ction exec tion time) an the n mb r of o erator

er ors made

For e c of the tasks (or clas of tasks) the n mb r of o erator ste s req ired s ould b

comp red with the n mb r of ste s esta ls ed in the analytical an the retical task

bre kdown

Althou h in this way the n mb rs o tained can ot b expres ed in an actual ef icien y

n mb r, it al ows rankin of s stems, when the o jective of the as es ment is to comp re

o era i ty of s stems

6.3.3 Intuitiv ne s

Usin the o servation of the analytical evaluation, the empirical evaluation of intuitivenes

s ould in practice b exec ted in p ral el with the evaluation of ef icien y as des rib d in

6.3.2

The seq en e of ste s made by the o erators, the n mb r of hesitation , re etition an

er ors made, an the ste s at whic these action oc ur s ould b recorded The n mb r of

6.3.4 Tra spare c

The analy is exec ted in 6.2.4 an the data o tained u der 6.3.3 s ould b careful y

analy ed together, sin e p rt of the recordin s of re etition an er ors made can b d e to

lack of tran p ren y

6.3.5 Robustne s

Op rational ro u tnes can b evaluated by the degre of ac e ted deviation from cor ect

input an the s stem re ction on multi-k y inputs or in or ect inputs (misprints) The s stem

can provide plau ibi ty an self cor ectin fu ction

The evaluation method for eficien y can b u ed an , if p s ible, b car ied out at the same

time, but s ould in lu e the fol owin :

– variation from the doc mented method an proced re;

– a sen e/presen e of s stem warnin s an ad ice when the method/proced re u ed is

ambig ou ;

– whether or not the o erator managed to recover the req ired o eration

6.4 Additional to ic for e alu tion te h iqu s

Op ra i ty can b afected by the influen in factors as stated in 4.2

It s ould b ta en into ac ou t that d rin some phases in the l fe c cle of the s stem,

o era i ty is req ired u der q ite diferent con ition than those whic normal y exist in a

control ro m Durin these phases, for example d rin the commis ionin an maintenan e

phase, the s stem can b exp sed to con ition , whic prevai in the proces are

Annex A

(informativ )

Checkl st and/or example of SRD for system operabi ity

The h man-mac ine interface not only gives the o erators a view of the s stem itself, but by

me n of it, they also control, monitor an reg late the in u trial proces con ected to the

s stem via its input output devices

The req irements for the o era i ty of a s stem not only come from al the diferent asp cts,

whic wi b en ou tered d rin the desig , en ine rin , commis ionin , o erational an

maintenan e phases of the s stem’s l fe c cle, but also are stron ly influen ed by the

p rson el u in the s stem an the en ironment the s stem is placed in

Partic lar at ention s ould b given to c eck that for e c of the s stem tasks the o era i ty

req irements are given with resp ct to:

– the phase of the s stem lfe c cle d rin whic the task s ould b p rformed;

– the d ration of e c phase an task(s);

– the minimum an maximum n mb r of o erators, who s ould u e the h man interface at

the same time to p rform the task(s);

– information a out the profi es of the o erators in olved, s c as their ed cation,

resp n ibi ty, role, ski an previou knowled e, etc

– protocols an method to b u ed, esp cial y asp cts req irin the o erators to u e the

s stem at the same time

The o era i ty req irements s ould have b en ad res ed b th in relation to in ivid al tasks

as wel as in relation to the total mis ion

A.2 Factors resulting from the industrial process itself

Some of the s stem o era i ty factors have to do with the in u trial proces u der control

Examples of these factors are:

a) Proces stru ture has an influen e on the presentation of the hierarc ical stru ture of the

information, s c as the n mb r of s b roces es, sin le or integrated o eration ; the

ph sical an ge gra hical location of the faci ties; b tc or contin ou o eration, etc

b) Proces modes of o eration (in lu ive start ups an s utdown ), their freq en y of

oc ur en e an d ration; contin ou o eration at fixed stan ard setin s or b tc

o eration req irin freq ent c an es from one mode of o eration to another at diferent

setin s, etc

c) Numb r an c aracteristic of the proces varia les, s c as: ac urac req ired, are the

varia les me s ra le, determination of proces state, mutual interaction of the proces

varia les, etc

d) Characteristic of the proces itself, esp cial y d namical asp cts s c as time con tants

of the (s b)proces es, batc d ration, c an in c aracteristic with lo d (l ne r/non

-l ne r), proces sta i ty an predicta i ty, etc

e) Potential hazardou con ition of proces (explosive atmosphere, toxicity, etc.)

Eac of these factors p s ibly req ire a c an e in the h man-mac ine interface an to b

A.3 Factors related with the task of the operators, their freque cy, percenta e

of time spent, required number of actions, etc

Some of the s stem o era i ty factors have to do with o erators, their freq en y, p rcentage

of time sp nt, req ired n mb r of action Examples of these factors are:

a) Proces control tasks:

1) modes of control (on/of, sta i sin , o timizin );

8) maintenan e diag ostic (preventive, c rative);

9) commu ication , etc

b) Tasks p rforman e criteria:

1) req ired ac urac of task p rforman e;

2) req ired sp ed of task p rforman e;

3) req ired resp n e time of h man-mac ine interface;

4) al owa le o erator’s faults (amou t an nature);

5) task priorities, etc

c) Op rator c aracteristic :

1) n mb r of o erators ( ield, control ro m);

2) commu ication req irements b twe n o erators/s p rvisors/other p rson el;

3) b ckgrou d (age, level of ed cation, exp rien e, trainin ), etc

d) Organizational:

1) al ocation of task b twe n field an control ro m p rson el;

2) authority levels in the u e of the h man-mac ine interface(s);

3) in tru tion an proced res;

4) organizational stru ture, etc

A.4 Factors due to the control strategy required

Some of the s stem o era i ty factors have to do with the control strateg req ired

Examples of these factors are:

a) Degre of automation:

1) n mb r of control lo ps (analog e/dis rete, PID/multivaria le, final control elements);

2) n mb r of plant protection lo ps;

3) n mb r of switc in action exec ted by the s stem, etc

b) Control strategies:

1) sin le, cas ade, ratio, ada tive, multi-varia le, fre programma le, etc an the

n mb r of e c kin

c) Control fu ction exec ted by the s stem:

1) on/of , sta i sin , o timization, lmitin an emergen y control, alarmin an alarm

d) Op rational asp cts:

1) interaction b twe n control lo ps;

2) malfu ction of lo ps (hard an sofware);

3) l mits on al owed/not alowed man al adju tments, etc

A.5 Factors concerning the human-ma hine interfa e design

Some of the s stem o era i ty factors have to do with the h man-mac ine interface desig

Examples of these factors are:

a) Sp cific information, whic can b req ired by o erators an further general asp cts s c

as amou t, complexity, update freq en y, seq en e, serial/p ral el presentation,

red n ant presentation, etc of the fol owin elements:

1) overal information on proces state, o erational values, etc

2) information on oc ur en e an location of deviation from req ired o eration;

3) clu tered information on es ential proces varia les;

4) information on historical an predicted future proces b haviour, etc

b) Intervention al owed:

1) switc in of proces plant eq ipment;

2) c an in set p ints, tu in p rameters, ac uirin information;

3) activatin an /or de ctivatin control s stem hard an sofware, etc

c) Me n for manipulation:

1) information asp cts ( orm, req ired amou t of action b fore comman exec tion,

codin , seq en e of input action , complexity, amou t of dif erent codes, etc.);

2) flexibi ty in code desig ;

3) u e of joy tick, track al, l g t p n, tou h s re n, k yb ard, mou e, gra hic ta let,

voice input, etc

d) Me n for providin information:

1) vide display u its: resolution, refres rate, fl ck r, contrast b twe n s mb l an

b ckgrou d, colours, size, image s arpnes an sta i ty, s re n profi e, s re n

orientation;

2) printers;

3) acou tic;

4) recorders, in icators, lamps, etc

A.6 Influenc of the workpla e on the opera i ity requirements

The layout of work lace is as folows:

a) workin p sture (stan in or sit in , he d p sition an movement, p stural lo din );

b) fo trest, arm s p ort;

c) dimen ion of workstation (work sp ce, desk heig t, s a e, p sition of output devices),

etc

d) distan e b twe n o erator an manipulation me n an information sources;

e) l g tin , noise, cl mate, vibration, dirt d st, comfort, etc

f control ro m desig : the materials an colours u ed for wal s, flo r, desks, cei n , etc

A.7 Ge eral human fa tors

Some of the s stem o era i ty factors have to do with the general h man factors Examples

of these factors are:

a) Ph sical lo d: workin p sture, movements to b exec ted, forces to b exercised,

n mb r an freq en y of action , etc

b) Mental lo d: memory lo d (s ort an lon term), req ired information proces in (amou t

an sp ed), etc

B.2 Check points for system operabi ity

Partic lar at ention s ould b p id to c eck that information, on a task-by- ask b sis, is

given on:

– the fu ction pro osed to s p ort the o era i ty asp cts of e c task;

– for e c fu ction the mod les an elements, b th hardware an sofware, s p ortin the

fu ction;

The level of detai n the implementation of the task(s) an the extent of s bdivision into

mod les an elements s ould b only that whic is neces ary, yet s f icient to demon trate

that the req irements are met

– the way in whic the interaction is provided for the o erator by the pro osed s stem in

terms of devices, method an proced res;

De en in on the arc itecture of the s stem, task(s) can b s p orted by alternative sets of

fu ction , whic can req ire alternative seq en es of o eration at the h man-mac ine

interface

– the ski s, exp rien e, etc to b req ired by the o erators to o erate the s stem pro erly,

an the to ls provided in s p ort of the o eration throu h the h man-mac ine interface;

– the u derlyin rationale if the s stem pro osed dif ers from the req irements or if diferent

alternative solution are s g ested, s p orted by data, for example stan ard , field

exp rien e, test re orts, calc lation , etc

The review s ould in p rtic lar examine whether for e c o erational phase the neces ary

information is given how the req ired tasks can b p rformed with the given group of

p rson el

Annex C

(informativ )

Example of a l st of assessment items (information from IEC TS 62603-1)

C.1 Ov rview

An ex C provides some examples a out influen in factors related to this stan ard whic

were extracted from IEC TS 6 6 3-1

The clas ification of the values of pro erties des rib d in this doc ment are only examples

C.2 Operabi ity properties of Huma Ma hine Interface (HMI)

C.2.1 Ge eral

In this g idel ne, the term HMI refers to the display , computers an sofware that serve as an

interface with a BPCS The HMI has thre primary fu ction :

a) provide vis al zation of proces p rameters an method with whic to control the

proces ;

b) provide alarms an in ication to the o erator when the proces is out of control or the

s stem has fai ed;

c) provide a method to al ow the o erator to u derstan where the proces is goin an how

fast ( ren in fu ctional ty)

To implement the HMI fu ctional ties, the sp cification of the req ired hardware an sof ware

req irements s ould b given It is imp rtant to distin uis the fu ction of the HMI in the

control ro m an the local o erator interface For b th the o tion , the hardware an sof ware

req irements s ould b in icated

C.2.2 Control room HMI hardware – s stem configuration

The minimum set of information for the control ro m hardware definition in lu es:

a) the req ired n mb r of mac ine;

b) the req ired n mb r of monitors;

c) the fu ctional ties of e c mac ine;

d) sp cial display, e.g overhe d projectors, wide s re n , etc (if an )

The control ro m s stem config ration can b efectively sp cified by a layout drawin

C.2.3 Control room HMI hardware – ma hin s

The control ro m network can b ef ectively sp cified by a drawin of the hardware s stem

C.2.5 Control room HMI hardware – spe ial displa s

Sp cial display are sp cified ac ordin to the req ired tec nolog , e.g overhe d projectors,

plasma or LED large s re n , b ck projectors, etc

C.2.6 Control room HMI sof ware

The sp cification for the HMI sof ware in lu e several fami es, as l sted hereinafer:

a) Tec nolog

1) Op ratin s stem, e.g Win ows XP

2) Sup orts ActiveX control ers

3) Based on OPC arc itecture

6) Horizontal an vertical p sition

7) Horizontal an vertical sl der

C.2.7 Re uireme ts for Loc l Operator Interfa e

It s ould b defined how man L cal Op rator Interface (LOI) s ould b in tal ed in the

s stem For e c LOI the req irements that s ould b defined are:

a) the p nel tec nolog : tou h or fu ction k y;

b) the sp cial k yb ard: buton for o eratin proces p rameters, buton for cal n up

display an buton for alpha et k y ;

c) the s re n size;

d) the s re n resolution in pixels;

e) the s p orted o eratin s stem;

f the s p orted commu ication p rts

Annex D

(informativ )

Phase of a system l fe cycle

Ta le D.1 s ows the variou phases, the o erator(s) u in the s stem d rin these phases,

their typical tasks an the typ of interfaces uti zed

Bibl ography

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Ev lu ato of system p ro erte s for th p u rp ose of system as es me t – Part 4:

As e ssme t ofsystem p erforma ce

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