1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationBS EN ISO 15091:2012Paints and varnishes Determination of electrical conductivity and r e s i s t a n c eBS EN ISO 15091:2012 BRITISH STANDARDNational forewordThis British Standa
2、rd is the UK implementation of EN ISO 15091:2012.The UK participation in its preparation was entrusted to Technical Committee STI/10, Test methods for paints.A list of organizations represented on this committee can be obtained on request to its secretary.This publication does not purport to include
3、 all the necessary provisions of a contract. Users are responsible for its correct application. The British Standards Institution 2013. Published by BSI Standards Limited 2013ISBN 978 0 580 70812 1 ICS 87.040 Compliance with a British Standard cannot confer immunity from legal obligations.This Briti
4、sh Standard was published under the authority of the Standards Policy and Strategy Committee on 28 February 2013.Amendments issued since publicationDate T e x t a f f e c t e dEUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 15091 December 2012 ICS 87.040 English Version Paints and varnishes
5、 - Determination of electrical conductivity and resistance (ISO 15091:2012) Peintures et vernis - Dtermination de la conductivit et de la rsistance lectriques (ISO 15091:2012) Beschichtungsstoffe - Bestimmung der elektrischen Leitfhigkeit und des elektrischen Widerstandes (ISO 15091:2012) This Europ
6、ean Standard was approved by CEN on 17 November 2012. CEN 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 c
7、oncerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN 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 CEN member
8、 into its own language and notified to the CEN-CENELEC Management Centre has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, Franc
9、e, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOM
10、ITEE FR NORMUNG Management Centre: Avenue Marnix 17, B-1000 Brussels 2012 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN ISO 15091:2012: EBS EN ISO 15091:2012EN ISO 15091:2012 (E) 3 Foreword This document (EN ISO 15091:2012) has b
11、een prepared by Technical Committee ISO/TC 35 “Paints and varnishes” in collaboration with Technical Committee CEN/TC 139 “Paints and varnishes” the secretariat of which is held by DIN. This European Standard shall be given the status of a national standard, either by publication of an identical tex
12、t or by endorsement, at the latest by June 2013, and conflicting national standards shall be withdrawn at the latest by June 2013. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN and/or CENELEC shall not be held responsible fo
13、r identifying any or all such patent rights. According to the CEN/CENELEC Internal Regulations, the national standards organisations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Forme
14、r Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. Endorsement notice The text of ISO 15091:2
15、012 has been approved by CEN as a EN ISO 15091:2012 without any modification. BS EN ISO 15091:2012ISO 15091:2012(E) ISO 2012 All rights reserved iiiContents PageForeword iv1 Scope 12 Normative references . 13 Terms and definitions . 14 General . 34.1 Measurement of the resistance . 34.2 Avoidance of
16、 electrolysis and polarization effects 45 Apparatus 55.1 Measuring instrument 55.2 Measuring cell 56 Sampling 57 Procedure 57.1 Test conditions . 57.2 Viscosity of test sample 67.3 Number of determinations 67.4 Measurement of the electrical resistance or the electrical conductivity . 68 Expression o
17、f results . 69 Precision 610 Test report . 7Annex A (normative) Calibration 8Annex B (informative) Dependence of the conductivity on the measurement temperature 10Bibliography . 11BS EN ISO 15091:2012ISO 15091:2012(E)ForewordISO (the International Organization for Standardization) is a worldwide fed
18、eration of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that comm
19、ittee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.International Standards are drafted in accordan
20、ce with the rules given in the ISO/IEC Directives, Part 2.The main task of technical committees is to prepare International Standards. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard requires a
21、pproval by at least 75 % of the member bodies casting a vote.Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights.ISO 15091 was prepared by Technical Commi
22、ttee ISO/TC 35, Paints and varnishes, Subcommittee SC 9, General test methods for paints and varnishes.iv ISO 2012 All rights reservedBS EN ISO 15091:2012INTERNATIONAL STANDARD ISO 15091:2012(E)Paints and varnishes Determination of electrical conductivity and resistance1 ScopeThis International Stan
23、dard specifies a method for determining the electrical conductivity and the electrical resistance of coating materials. The conductivity is usually measured for water-borne paints and varnishes, including electrodeposition coating materials, and the resistance is usually measured for solvent-borne p
24、aints and varnishes. If required, the resistivity of the coating material is calculated from either of these measurements. The method is applicable to products having a conductivity less than 5 S/cm, corresponding to a resistivity greater than 200 kcm.The conductivity of coating materials influences
25、 their processibility in the presence of an electric field. This is particularly important for electrodeposition paints and coating materials which are processed electrostatically.2 Normative referencesThe following referenced documents are indispensable for the application of this document. For dat
26、ed references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.ISO 1513, Paints and varnishes Examination and preparation of test samplesISO 3696, Water for analytical laboratory use Specification and test metho
27、dsISO 15528, Paints, varnishes and raw materials for paints and varnishes Sampling3 Terms and definitionsFor the purposes of this document, the following terms and definitions apply.3.1electrical resistanceRratio of the potential difference along a conductor and the current through the conductorNOTE
28、 Resistance is given by Ohms law:RUI= (1)whereU is the potential difference;I is the current.The unit of electrical resistance is the ohm (), given by:111ohmvoltampere=The electrical resistance depends on the material of the conductor, its dimensions (length and cross-section) and its temperature. I
29、SO 2012 All rights reserved 1BS EN ISO 15091:2012ISO 15091:2012(E)3.2resistivityresistance per unit length of a material of unit cross-sectional areaNOTE Resistivity is given by Equation (2): =RAl(2)whereA is the cross-sectional area of the conductor;l is the length of the conductor.The unit of resi
30、stivity is the ohm metre (m).3.3conductanceGreciprocal of the resistanceNOTE Conductance is given by Equation (3):GRIU=1(3)The unit of conductance is the siemens (S):1111Sohmamperevolt=3.4electrical conductivityreciprocal of the resistivityNOTE Electrical conductivity is given by Equation (4):=11RlA
31、(4)The unit of electrical conductivity is the siemens reciprocal metre (Sm1).3.5cell constantcquotient of the length and the cross-sectional area of a conductorNOTE It is given by Equation (5):clA= (5)From Equation (2), it can be seen that it corresponds to the ratio of the resistance to the resisti
32、vity of the conductor material.For the determination of the resistivity by resistance measurement, this geometrical factor, i.e. the cell constant of the measurement assembly, will need to be known.Cell constants are given in reciprocal centimetres (cm1).2 ISO 2012 All rights reservedBS EN ISO 15091
33、:2012ISO 15091:2012(E)4 General4.1 Measurement of the resistanceThe resistance may be determined by measurement of the current through a sample and the voltage acting on the sample;or comparison of the measured resistance with a reference resistance.For the current/voltage measurement, usually a con
34、stant pre-determined voltage is applied to the sample, and the current is measured with a suitable measuring instrument (e.g. a moving-coil instrument or a digital instrument). The resistance is then calculated from Equation (1). See Figures 1 to 3.Figure 1 Direct-current measurementFigure 2 Alterna
35、ting-current measurement Two-electrode cell ISO 2012 All rights reserved 3BS EN ISO 15091:2012ISO 15091:2012(E)Figure 3 Alternating-current measurement Four-electrode cellTo compare the resistance of the sample with a reference resistance, a bridge circuit is used in which the resistances are balanc
36、ed so that the bridge current becomes zero. The resistance of the sample is calculated from the ratio of the resistances of the bridge circuit. Because the bridge current is zero, errors which can result from the existence of a load on the voltage source when the voltage/current measurement method i
37、s used are avoided. The only contributions to the overall measurement error are any uncertainty in the reference resistance and any uncertainty in the adjustable resistance. See Figure 4.RRabx=Figure 4 Wheatstone bridge4.2 Avoidance of electrolysis and polarization effectsIn order to avoid electroly
38、sis or polarization effects which would falsify the measurement, measurements of the resistance are usually carried out using alternating current. The frequency of the voltage applied to the measuring cell should, however, be as low as possible in order to minimize the contribution made by the react
39、ance of the measuring cell, which acts as a capacitor.4 ISO 2012 All rights reservedBS EN ISO 15091:2012ISO 15091:2012(E)5 Apparatus5.1 Measuring instrumentUse a resistance- or conductivity-measuring instrument calibrated as described in Annex A.5.2 Measuring cellThe measuring cell consists of elect
40、rodes insulated from each other, with a known cell constant. The electrodes should preferably consist of a material that is easy to clean and inert (e.g. stainless steel, platinum, graphite, titanium) in order to make sure that the measurement will not be invalidated by changes in the electrodes. Fo
41、r examples of suitable electrodes, see Figure 5. It is important to ensure that the measuring cell is completely immersed in the liquid. The exact depth will depend on the type of electrode.The cell geometry shall be chosen so that the possibility of contamination by dirt is minimized.a) Measuring c
42、ell with cylinder electrodes b) Measuring cell with plate electrodesFigure 5 Examples of measuring cells6 SamplingTake a representative sample of the product to be tested, as described in ISO 15528.Examine and prepare each sample for testing, as described in ISO 1513.7 Procedure7.1 Test conditionsCa
43、rry out the test at a temperature of (25 1) C, unless otherwise agreed. The deviation from any agreed temperature shall also be not more than 1 C.The dependence of the conductivity on the measurement temperature is shown in Annex B. ISO 2012 All rights reserved 5BS EN ISO 15091:2012ISO 15091:2012(E)
44、7.2 Viscosity of test sampleThe test is usually carried out at the same viscosity as that of the product under test when it is ready for use. The solvent used to adjust the viscosity, if this is necessary, shall be agreed between the interested parties.7.3 Number of determinationsMake at least three
45、 individual measurements on the product under test.7.4 Measurement of the electrical resistance or the electrical conductivityTake the required quantity of the paint sample and immerse the electrodes in it, avoiding the formation of bubbles. If required, homogenize the material before doing this.Pri
46、or to the measurement, check the measuring cell for cleanliness and remove any particles of dirt. Connect the measuring cell to the measuring instrument. For measurements using a direct-current measuring instrument, e.g. a Wheatstone bridge, read the value after a waiting time of 10 s in order to al
47、low the electrical potential to become constant. For measurements using an alternating-current measuring instrument, read the value after an agreed waiting time.When using continuously measuring instruments, the value shall only be read if it is constant for more than 20 s.Immediately after the test
48、, thoroughly clean the measuring cell.8 Expression of resultsCalculate the mean of the at least three individual measurements made of the resistance or conductivity. If required, calculate the resistivity from this mean value, using Equation (2) if resistance measurements were made or Equation (4) i
49、f conductivity measurements were made. Examples of the calculation of the resistivity from the measurements are given below, using typical values.EXAMPLE 1: Calculation of the resistivity from resistance measurementsMean resistance reading, R M 1,22Mean resistance reading, R k 1 220Cell constant, c cm17,55 103Resistivity, Mcm 161,6Resistivity, Mm 1,62EXAMPLE 2: Calculation of the resistivity from conductivity measurementsMean conductivity reading, S/cm 1,375Mean conductivity reading,
