BS EN 61000-3-3:2013 BSI Standards Publication Electromagnetic compatibility (EMC) Part 3-3: Limits – Limitation of voltage changes, voltage fluctuations and flicker in public low-voltage supply systems, for equipment with rated current ≤ 16 A per phase and not subject to conditional connection BS EN 61000-3-3:2013 BRITISH STANDARD Text affected EUROPEAN STANDARD EN 61000-3-3 NORME EUROPÉENNE EUROPÄISCHE NORM August 2013 ICS 33.100.10 Supersedes EN 61000-3-3:2008 English version Electromagnetic compatibility (EMC) - Part 3-3: Limits - Limitation of voltage changes, voltage fluctuations and flicker in public low-voltage supply systems, for equipment with rated current ≤ 16 A per phase and not subject to conditional connection (IEC 61000-3-3:2013) Compatibilité électromagnétique (CEM) - Elektromagnetische Verträglichkeit Partie 3-3: Limites - (EMV) - Limitation des variations de tension, des Teil 3-3: Grenzwerte - fluctuations de tension et du papillotement Begrenzung von Spannungsänderungen, dans les réseaux publics d'alimentation Spannungsschwankungen und Flicker in basse tension, pour les matériels ayant un öffentlichen Niederspannungs- courant assigné ≤ 16 A par phase et non Versorgungsnetzen für Geräte mit einem soumis un raccordement conditionnel Bemessungsstrom ≤ 16 A je Leiter, die (CEI 61000-3-3:2013) keiner Sonderanschlussbedingung unterliegen (IEC 61000-3-3:2013) This European Standard was approved by CENELEC on 2013-06-18 CENELEC members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CENELEC member This European Standard exists in three official versions (English, French, German) A version in any other language made by translation under the responsibility of a CENELEC member into its own language and notified to the CEN-CENELEC Management Centre has the same status as the official versions CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom CENELEC European Committee for Electrotechnical Standardization Comité Européen de Normalisation Electrotechnique Europäisches Komitee für Elektrotechnische Normung Management Centre: Avenue Marnix 17, B - 1000 Brussels © 2013 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members Ref No EN 61000-3-3:2013 E BS EN 61000-3-3:2013 – – EN 61000-3-3:2013 -2- EN 61000-3-3:2013 Foreword The text of document 77A/809/FDIS, future edition of IEC 61000-3-3, prepared by SC 77A, "EMC - Low frequency phenomena", of IEC TC 77, "Electromagnetic compatibility" was submitted to the IEC-CENELEC parallel vote and approved by CENELEC as EN 61000-3-3:2013 The following dates are fixed: • latest date by which the document has (dop) 2014-03-18 to be implemented at national level by (dow) 2016-06-18 publication of an identical national standard or by endorsement • latest date by which the national standards conflicting with the document have to be withdrawn This document supersedes EN 61000-3-3:2008 EN 61000-3-3:2013 includes the following significant technical changes with respect to EN 61000-3-3:2008: This edition takes account of the changes made in EN 61000-4-15:2011 Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights CENELEC [and/or CEN] shall not be held responsible for identifying any or all such patent rights This document has been prepared under a mandate given to CENELEC by the European Commission and the European Free Trade Association, and supports essential requirements of EU Directive(s) For the relationship with EU Directive(s) see informative Annex ZZ, which is an integral part of this document Endorsement notice The text of the International Standard IEC 61000-3-3:2013 was approved by CENELEC as a European Standard without any modification – – BS EN 61000-3-3:2013 -3- EN 61000-3-3:2013 EN 61000-3-3:2013 Annex ZA (normative) Normative references to international publications with their corresponding European publications The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application For dated references, only the edition cited applies For undated references, the latest edition of the referenced document (including any amendments) applies NOTE When an international publication has been modified by common modifications, indicated by (mod), the relevant EN/HD applies Publication Year Title EN/HD Year IEC/TR 60725 - - Consideration of reference impedances and - IEC 60974-1 - public supply network impedances for use in - IEC 61000-3-2 - determining disturbance characteristics of - electrical equipment having a rated current - IEC 61000-3-11 - ≤ 75 A per phase 2011 IEC 61000-4-15 2010 Arc welding equipment - EN 60974-1 + corr March 2012 Part 1: Welding power sources Electromagnetic compatibility (EMC) - EN 61000-3-2 Part 3-2: Limits - Limits for harmonic current emissions (equipment input current ≤ 16 A per phase) Electromagnetic compatibility (EMC) - EN 61000-3-11 Part 3-11: Limits - Limitation of voltage changes, voltage fluctuations and flicker in public low-voltage supply systems - Equipment with rated current ≤ 75 A and subject to conditional connection Electromagnetic compatibility (EMC) - EN 61000-4-15 Part 4-15: Testing and measurement techniques - Flickermeter - Functional and design specifications BS EN 61000-3-3:2013 – – EN 61000-3-3:2013 -4- EN 61000-3-3:2013 Annex ZZ (informative) Coverage of Essential Requirements of EU Directives This European Standard has been prepared under a mandate given to CENELEC by the European Commission and the European Free Trade Association and within its scope the standard covers protection requirements of Annex I Article 1(a) of the EU Directive 2004/108/EC and protection requirements of Article 3.1(b) (emissions only) of the EU Directive 1999/5/EC Compliance with this standard provides one means of conformity with the specified essential requirements of the Directives concerned WARNING: Other requirements and other EU Directives may be applicable to the products falling within the scope of this standard – – 61000-3-3 © IEC:2013 – – 61000-3-3 © IEC:2013 – – 6B1S00E0N-36-130©00I-E3C-3::22001133 CONT–E5N–TS EN 61000-3-3:2013 CON–T2E–NTS 61000-3-3 © IEC:2013 FOREWORD C O N T E N T S FOREW ORD IFNOTRREOWDOURCDTI.O N C O N T E N T S 46 INTRODUCTION 1INTRSOcoDpUeC T I.O N 76 1FORSEcWopOeR D 74 21 NScoormpea.t.i.v.e r.e f.e r e.n c e s 2INTRNOoDrmUaCtiTvIeOrNef.e r e.n c e s 76 32 TNeormsataivned rdeefefirneintiocens .87 31 TSecrompes a n d d e f.i.n it.i.o n s 78 43 ATessrmesssamnedndt eoffinviotilotangse c h a n g e s., v.o l.t.a g e f.l.u c.t.u a t.i.o n s a.n d f.l.i.c k.e r .1.08 42 ANsosrmesastmivenrteofefrveonlctaegse c h a n g e s., v.o l.t.a g e f.l.u c.t.u a t.i.o n s a.n d f.l.i.c k.e r .1.07 4A.s1sesAsmsseenstsomf evnotltoafgae rcehlantigvesv,ovltoaltgaegechfaluncgteu,atdi(otn).s a.n d f.l.i.c k.e r 10 4T.e1rmsAasnsdesdsemfiennittioonfsa r.e l.a t.i.v e v.o l.t.a g e c h a.n g e , d (.t.) 1.08 44 12 AAsssseessssmmeenntt ooff tahereslahtoivret-tveormltagfleickcehravnagleu,ed, (Pt)s t 1100 4A.s2sesAsmsseenstsomf evnotltoafgtehechsahnogret-ste, rvmoltfalicgkeefrluvcatluuaet,ioPnsst a.n d f.l.i.c k.e r 10 4.2 4A.s2s.e1ssmGeennteoraf lth e s h o r.t.-.t.e r.m f.l.i.c k.e r v a l.u e , P s t 1100 4.1 44A s22s e21ssmFGleeicnnkteeorrafmla.e.rt.ee lr.a t i v e v o l t a g e c h a n g e , d ( t ) 111100 4.2.1 General 10 4.2 44A s22s e32ssmSFleiimcnktueloarfmtitohenetemsr h.e.ot.h.r.to.-.td.e r m f l i c k e r v a l u e , P s t 111110 4.2.2 Flickermeter 11 444 222 431 ASGniemanuleylrtaaictliao ln.m m.e et.ht.h.o.o.d.d 111110 4.2.3 Simulation method .11 444 222 542 UAFlnsiceaklyoetfrimcPaeltme=re1.t.h.c.o.u.d.r.v e 111211 4.2.4 Analyticasltmethod 11 4.3 A44 s22s e53ssmUSeismnetuoloafftPiloosnnt g=m-t1eetrchmuordfvl.ei.c.k e r v a l u e , P 111221 4.2.5 Use of Pst = curve l.t 12 L4.im3 itsA4 s.2.s e.4.s s mA en.n.a.t.ly.o.t.if.c.l.ao ln.m.g -e.t.et.h.r.om d f l i c k e r v a l u e , P l t 111221 4.3 Assessment of long-term flicker value, Plt .12 Limits4 U s e o.f P s.t = c u r.v e 1122 65 TLiemsittsco n d i.t.io n s 132 T4.e3st cAosnsdeitsiosnmse.n t o f l.o n g -.t.e r.m f.l.i.c.k e r v a l.u e , P l.t 123 6T.e1st cGonednietiroanl s 13 6L.im1 itsG e n e r.a l 123 66 21 MGeenaesruarel m e n t u n.c e r.t.a i.n t.y 1143 6T.e2st cMonedaistiuornesm e n t u n.c e r.t.a i.n t.y 134 66 32 TMeesatssuurpepmlyenvtoultnacgeert.a i.n t.y 1144 666 431 RTGeeesfnetersreuanplc.p.e.l.y.im.v op le.t.ad ga en c e 111443 6.3 Test supply voltage 14 666 542 ORMebefsaeesrruevrnaectmeioenimnptpeuerndiocadenr.ct.a.e.i n t y 111444 6.4 Reference impedance 14 666 653 GOTeebssnteesrrvuaapl tptieolysntvpcoeoltrnaiodgideti.o n s 111544 6.5 Observation period 14 Anne66x 64A (nGRoeerfnmeeraretanivlcetee)simtAcppopenldidcaiantitcoioenn.s o f l i m i t s a n d t y p e t e s t c o n d it i o n s f o r s p e c i f i c 1154 6.6 General test conditions 15 eAqnunie6px.m5Aen(tnO.o.b.r.sm e.a.r.vt.i.av te.i.o).n A.p.p.e.p.r.li.io.c.da t.i.o n o f l.i.m i.t.s a n d t.y p.e t.e s t c o n d it.i.o n s f.o r s p e c.i.f.i.c 194 AeqnuniepxmAen(tn.o r.m a t.i.v e ) A p p l.i.c.a t.i.o n o f l.i.m i.t.s a n d t.y p.e t.e s t c o n d it.i.o n s f.o r s p e c.i.f.i.c 19 Aeqnunie6px.m6Ben(tnG.o.e.r.nm e.a.r.ta.i.vl et.e.).s tT ce.o.s.n.t.d.c.io.t.in.o.d.n.i.st.i o n s a n d p r o c e d u r e s f o r m e a s u r i n g d m a x v o lt a g e 1195 cAAhnnannneegxxeBAs c((nnaoourrsmmeaadttiibvvyee))maTAnepuspatlilccsoawntioditnictihooinnf sglima ni.t.ds ap nr.o.d.c te.y.dp ue r.et.e.s.s.f.to cr o.m.n.e.d.a.it.si.o.u.n.r.si.n fg.o dr.m.s pa ex.c vi.f.oi.c.lt.a g e 27 cAehqnaunniepgxmeBsenc(tna.o.u.r.sm.e ad t.ib.v.y.e )m aT ne us at.l.c.so wn di.t.ic.t.ih.o.i.nn sg a n d p r o c e d u r e s f o r m e a s u r i n g d m a x v o lt a g e 2179 cAhnannegxeCs c(ianufosremdabtiyvem)aDnueatel rsmwiintcahtiionng o f s t.e a d y s t.a t.e v o l.t.a g.e a n d v o l.t.a g.e c h a n g e 27 cAAhnnannreeaxxctCBer((insintoifcromsrm,aataisvtievd)ee)fTinDeesedttecinromnIEidnCiatito6ion1ns00oa0fn-ds4t-ep1ar5od:cy2e0sd1tua0rtee s.v.f.oo lr.t.a.mg ee a.a.s.n.u.d.r.i.nv og l.td.am.g ae x.c vh oa lnt.a.g.g.e.e 28 cAhnanreaxctCer(isintifcosrm, aastivdee)finDeedteinrmIEinCat6io1n00o0f -s4t-e1a5d:y20s1ta0te v o l.t.a.g e a n d v o l.t.a.g e c h a n g e 28 ccAhhnaanrneagxcetDserc(isiantuifcossrem,daabstiyvdeme)fainnIenudpaulintsrwIeEiltaCcthi6vine1g0v0.o.0.l.t-.a4.g.-.1e 5.f.:l.2u 0c 1t.u.0.a t i o n ∆ V / V f o r P s t = , a t o u t p u t 2278 [AAIEnnnnCee/TxxRDC6((1iinn0ff0oo0rrmm-3aa-tt7iivv:2ee0)) 0DI8n]ep.t.ue tr.m.r.e.i.nl.a.a.t.itv.io.e.n v.o.o.f.l.ts.a.t.ge.e.a df.l.yu cs tt.ua at.e.t.i.ov.n.o l∆.t.a.V.g./e.V a.f.on rd P.v.s.o.t.l.t=.a g1.e.,.0.c ah ta on ug te.p u t 33 [cAIhEnanCre/aTxcRtDer6(i1sint0ifc0os0rm,-3aa-st7ivd:2ee0)fi0nI8en]dp u.i.nt rI.e.E.l.aC t.i6v e1 0.v.0.o.0.l.t-.a4 g-.1e 5.f.:l.2u 0c 1t.u.0.a t i o n ∆ V / V f o r P s t = , a t o u t p u t 3238 [BIEibClio/TgRra6p1h0y0 -.3 -.7 :.2 0 ] 334 BAinbnlieoxgrDap(ihnyfo r.m a t.i.v e ) I.n p u t r.e l.a t.iv e v o l.t.a g.e f.l.u c t.u a t.i.o.n ∆ V /.V f.o r P = ,.0 a t o u t.p u t 34 Bibliography s t 34 [IEC/TR 61000-3-7:2008] 33 Figure – Reference network for single-phase and three-phase supplies derived from aFBitgbhulrioreeger-1app–hhaRyse.e.f.,e fr.oe un.r.c.-.we i.nr.e.e ts.w.u.o.p.r.pk l.yf.o r s i n g le - p h a s e a n d t h r e e - p h a s e s u p p l ie s d e r i v e d f r o m 1364 aFitghurreee-1p–haRseef,efroeunrc-we inreetswuoprpklyfo r s i.n g le - p.h a s e a n d t.h r.e e -.p h a s.e s u p p l.ie s d e r.i.v e d f.r o m 16 aFitghurreee-2p–haCsuer,vfeoufor-rwPirset =su1ppfolyr r.e c t.a n g u l.a.r e q.u i.d i.s t.a n t v.o l.t.a g e c h.a n g e s 176 FFiigguurree 21 –– CRuerfeverefnocrePnset t=w1orfkorforrescitnagnlgeu-plahraesqeuaidnidsttahnrteveo-plthaagseecshuapnpgleiess d e r.i.v e.d f.r o m 17 Figure 32 – SChuarvpee ffoarcPtosrts=F1fofor rdroeucbtalen-gsutelapr aenqduirdaimstpa-nvtovltoalgtaegcehcahranctgeersis.t.i.c.s 17 aFitghurreee-3p–haSshea, pfoeufra-cwtiorerssFupfoprlyd o.u b l.e -.s t.e p a n d r.a m p.- v.o l.t.a g e c h.a r a.c t.e r.i.s t.i.c s 176 Figure 43 – Shape factors F for dreocutbalneg-ustlaerp aanndd traiamnpg-uvloalrtavgoeltacghearcahcateraricstteicriss.t.i.c.s 178 Figure 42 – SChuarvpee ffoarcPtosrts=F1fofor rrerecctatanngguulalar raenqdutirdiaisntgauntlavrovltoaltgaegcehcahnagreasct.e r.i.s t.i.c.s 178 Figure 54 – Shape factorsFFfofor rmroetcotar-nsgtaurltavr oalntadgteriacnhgarualacrtevroisltaicgsehcahvainragcvtearriisotuicssf.r.o n t 18 tFimigeusre 53 – S h a p e f.a c t.o.r s.F.F f.of or.r.m d.o.o.tu.o.b.r.-l.se t-.as rt.te vp o.a.lt.na dg e.r.a.c.m.h pa.-.r.va.o.c.l.tt.ea.r.g.is.e.t.i.c hs.a hr.a vc it.ne gr.i.s.v.t.ai.cr sio u s f r o n t 1178 tFFimiiggeuusrree 54 –– SS hh aa pp ee ff.aa cc tt.oo.rr s.F.F f.of or.r.m r.oe tc.ot.a.r.-n.s.g.t.au rl.ta vr oa lnt.a.d.g te.r.i.ac nh ga ru.a.la.c.r.t.e.vr.o.is.l.tt.ai.c.g.s.e h.ca hv.a.i.nr ag.c vt.e.a.rr.i.iso tu.i.cs.s f r o n t 1188 tFimigeusre C – E v.a l.u a t.i.o n o f U h p (.t.) 3128 FFiigguurree C5 –1 S–hEavpaelufaactitoonr oFffUorhmp(ot)t.o.r -.s t.a r.t v o.l.t.a g e c h a r.a c.t.e r is t.i.c s h.a v i.n g v.a r io u s f.r.o n t 32 Figure C.1 – Evaluation of Uhp(t) 32 times 18 Table – Assessment method 11 TFiagbulree1C–.1A–ssEevsaslmuaetniot nmoefthUohdp.(.t.) 3121 Table 1A.–1 A–sTseesstscmoenndtitmioentshofodr h o.t.p l.a t.e s 191 Table A.1 – Test conditions for hotplates 19 Table A.21 – TEelescttrcoodnediptiaornasmfeotrehrsot.p l.a t.e s 2149 6T1a0b0le0-1A3.–-23A–©sEsIleEesCcst:rm2o0ed1ne3t pmaerathmoedte r.s – – 2141 Table A.32 – FErlecqturoednecypfaarcatmoreRtersel.a t.e d t.o r.e p e t.i.t.i.o.n r a.t e " r." 254 Table A.31 – TFreesqt uceonncdyitifoancstofroRr hreoltaptleadtetso r.e p e t.i.t.i.o.n r a.t.e " r." 2159 Table CA.31 – FTreesqt usepneccyififcaacttioornRforreldacte–ddtmo arexp–etidt(iot)n>ra3t,e3 "%r"( f.r.o m T a b le o f 25 Table A.2 – Electrode parameters 24 IEC 61000-4-15: 2010) 31 Table A.3 – Frequency factor R related to repetition rate "r" 25 Table C.2 – Test specification for dc – dmax – td(t) > 3,3 % (from Table 13 of IEC 61000-4-15: 2010) 31 Table D.1 – Input relative voltage fluctuation ∆V/V for Pst = 1,0 at output .33 BS EN 61000-3-3:2013 – – EN 61000-3-3:2013 – – 61000-3-3 © IEC:2013 INTRODUCTION IEC 61000 is published in separate parts according to the following structure: Part 1: General General considerations (introduction, fundamental principles) Definitions, terminology Part 2: Environment Description of the environment Classification of the environment Compatibility levels Part 3: Limits Emission limits Immunity limits (in so far as they not fall under the responsibility of product committees) Part 4: Testing and measurement techniques Measurement techniques Testing techniques Part 5: Installation and mitigation guidelines Installation guidelines Mitigation methods and devices Part 9: Miscellaneous Each part is further subdivided into sections which are to be published either as International Standards or as Technical Reports These standards and reports will be published in chronological order and numbered accordingly – – BS EN 61000-3-3:2013 EN 61000-3-3:2013 61000-3-3 © IEC:2013 – – ELECTROMAGNETIC COMPATIBILITY (EMC) – Part 3-3: Limits – Limitation of voltage changes, voltage fluctuations and flicker in public low-voltage supply systems, for equipment with rated current ≤ 16 A per phase and not subject to conditional connection Scope This part of IEC 61000 is concerned with the limitation of voltage fluctuations and flicker impressed on the public low-voltage system It specifies limits of voltage changes which may be produced by an equipment tested under specified conditions and gives guidance on methods of assessment This part of IEC 61000 is applicable to electrical and electronic equipment having an input current equal to or less than 16 A per phase, intended to be connected to public low-voltage distribution systems of between 220 V and 250 V line to neutral at 50 Hz, and not subject to conditional connection Equipment which does not comply with the limits of this part of IEC 61000 when tested with the reference impedance Zref of 6.4, and which therefore cannot be declared compliant with this part, may be retested or evaluated to show conformity with IEC 61000-3-11 Part 3-11 is applicable to equipment with rated input current ≤ 75 A per phase and subject to conditional connection The tests according to this part are type tests Particular test conditions are given in Annex A and the test circuit is shown in Figure NOTE The limits in this standard relate to the voltage changes experienced by consumers connected at the interface between the public supply low-voltage network and the equipment user’s installation Consequently, if the actual impedance of the supply at the supply terminals of equipment connected within the equipment user’s installation exceeds the test impedance, it is possible that supply disturbance exceeding the limits could occur NOTE The limits in this standard are based mainly on the subjective severity of flicker imposed on the light from 230 V 60 W coiled-coil filament lamps by fluctuations of the supply voltage For systems with nominal voltage less than 220 V line to neutral and/or frequency of 60 Hz, the limits and reference circuit values are under consideration Normative references The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application For dated references, only the edition cited applies For undated references, the latest edition of the referenced document (including any amendments) applies IEC/TR 60725, Consideration of reference impedances and public supply impedances for use in determining disturbance characteristics of electrical equipment having a rated current ≤ 75 A per phase IEC 60974-1, Arc welding equipment – Part 1: Welding power sources IEC 61000-3-2, Electromagnetic compatibility (EMC) – Part 3-2: Limits – Limits for harmonic current emissions (equipment input current ≤ 16 A per phase) BS EN 61000-3-3:2013 – – EN 61000-3-3:2013 – – 61000-3-3 © IEC:2013 IEC 61000-3-11, Electromagnetic compatibility (EMC) – Part 3-11: Limits – Limitation of voltage changes, voltage fluctuations and flicker in public low-voltage supply systems – Equipment with rated current ≤ 75 A and subject to conditional connection IEC 61000-4-15:2010, Electromagnetic compatibility (EMC) – Part 4-15: Testing and measurement techniques – Flickermeter – Functional and design specifications Terms and definitions For the purposes of this document, the following terms and definitions apply 3.1 flicker impression of unsteadiness of visual sensation induced by a light stimulus whose luminance or spectral distribution fluctuates with time [SOURCE: IEC 60050-161:1990, 161-08-13] 3.2 voltage change characteristic d(t) time function of the relative r.m.s voltage change evaluated as a single value for each successive half period between zero-crossings of the source voltage, except during time intervals in which the voltage is in a steady-state condition for at least s Note to entry: For detailed information about the evaluation of a voltage change characteristic and the definition of a steady state condition see Annex C and IEC 61000-4-15:2010 3.3 dc maximum steady state voltage change during an observation period Note to entry: For detailed information about the calculation of dc see Annex C and IEC 61000-4-15:2010 3.4 dmax maximum absolute voltage change during an observation period Note to entry: For detailed information about the calculation of dmax see Annex C and IEC 61000-4-15:2010 3.5 Tmax maximum time duration during the observation period that the voltage deviation d(t) exceeds the limit for dc Note to entry: During a voltage change characteristic the time duration Tmax is accumulated until a new steady state condition is established Note to entry: The Tmax limit evaluation in this standard is generally intended to evaluate the inrush current pattern of the equipment under test Thus, as soon as a new steady state condition is established, the Tmax evaluation is ended When a new voltage change occurs that exceeds the limit for dc, a new Tmax evaluation is started The maximum duration that d(t) exceeds the limit for dc for any of the individual Tmax evaluations during the observation period, is used for the comparison against the Tmax limit, and is reported for the test 3.6 nominal test voltage Un nominal test voltage used to calculate percentages for the various directly measured parameters