1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationBS EN 14617-13:2013Agglomerated stone TestmethodsPart 13: Determination of electricalresistivityBS EN 14617-13:2013 BRITISH STANDARDNational forewordThis British Standard is the
2、UK implementation of EN 14617-13:2013.It supersedes BS EN 14617-13:2005 which is withdrawn.The UK participation in its preparation was entrusted to TechnicalCommittee B/545, Natural stone.A list of organizations represented on this committee can beobtained on request to its secretary.This publicatio
3、n does not purport to include all the necessaryprovisions of a contract. Users are responsible for its correctapplication. The British Standards Institution 2013. Published by BSI StandardsLimited 2013ISBN 978 0 580 79617 3ICS 91.100.15Compliance with a British Standard cannot confer immunity fromle
4、gal obligations.This British Standard was published under the authority of theStandards Policy and Strategy Committee on 30 April 2013.Amendments issued since publicationDate Text affectedBS EN 14617-13:2013EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 14617-13 April 2013 ICS 91.100.15 Supers
5、edes EN 14617-13:2005English Version Agglomerated stone - Test methods - Part 13: Determination of electrical resistivity Pierre agglomre - Mthodes dessai - Partie 13 : Dtermination de la rsistivit lectrique Knstlich hergestellter Stein - Prfverfahren - Teil 13: Bestimmung des spezifischen elektrisc
6、hen Widerstands This European Standard was approved by CEN on 1 March 2013. 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 biblio
7、graphical references concerning 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 responsi
8、bility of a CEN member 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 Republ
9、ic 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 United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALI
10、SATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: Avenue Marnix 17, B-1000 Brussels 2013 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 14617-13:2013: EBS EN 14617-13:2013EN 14617-13:2013 (E) 2 Contents Page Foreword 3 1 Sc
11、ope 4 2 Normative references 4 3 Principle 4 4 Terms and definitions and symbols 4 5 Sampling and test specimen preparation .5 6 Specimen conditioning .5 7 Electrode system and measuring equipment .6 8 Procedure .6 9 Expression of results 6 10 Report .7 Annex A (informative) DC electrical conduction
12、 and polarisation phenomena in insulating materials 10 Annex B (informative) Statistical evaluation of test results. 12 B.1 Scope . 12 B.2 Symbols and definitions 12 B.3 Statistical evaluation of test results . 12 Annex C (informative) Determination of DC volume resistance and resistivity and the co
13、rresponding electrical conductance and conductivity . 14 C.1 Scope . 14 C.2 Test specimen preparation 14 C.3 Specimen conditioning 14 C.4 Electrode system and measuring equipment 14 C.5 Procedure 14 C.6 Expression of results . 15 C.7 Report 15 Bibliography . 16 BS EN 14617-13:2013EN 14617-13:2013 (E
14、) 3 Foreword This document (EN 14617-13:2013) has been prepared by Technical Committee CEN/TC 246 “Natural stones”, the secretariat of which is held by UNI. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the l
15、atest by October 2013, and conflicting national standards shall be withdrawn at the latest by October 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 for identifying any or al
16、l such patent rights. This document supersedes EN 14617-13:2005. Clauses 6, 7, 8, 9 and 10 have been modified and a new Annex C has been added since the last edition of this European Standard. This European Standard is one of a series of standards for test methods for agglomerated stones which inclu
17、des the following: Part 1: Determination of apparent density and water absorption Part 2: Determination of flexural strength (bending) Part 4: Determination of the abrasion resistance Part 5: Determination of freeze and thaw resistance Part 6: Determination of thermal shock resistance Part 8: Determ
18、ination of resistance to fixing (dowel hole) Part 9: Determination of impact resistance Part 10: Determination of chemical resistance Part 11: Determination of linear thermal expansion coefficient Part 12: Determination of dimensional stability Part 13: Determination of electrical resistivity Part 1
19、5: Determination of compressive strength Part 16: Determination of dimensions, geometric characteristics and surface quality of modular tiles According to the CEN-CENELEC Internal Regulations, the national standards organisations of the following countries are bound to implement this European Standa
20、rd: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spai
21、n, Sweden, Switzerland, Turkey and the United Kingdom. BS EN 14617-13:2013EN 14617-13:2013 (E) 4 1 Scope This European Standard covers the determination of DC insulation resistance, surface resistance and resistivity, and the corresponding electrical conductance and conductivity of specimens of aggl
22、omerated stone products conforming to the definition reported in EN 14618. These products are usually made by stone aggregates bound via either resin and filler or cement and water (paste components), or a mixture of polymer/cement and related addition (such as reinforcing fibres, electrically insul
23、ating/conducting fillers, etc.). Resistivity/conductivity may also be used as an indirect measure of some properties of agglomerated stone products (see Annex A - informative). Volume resistance and resistivity test method and the corresponding electrical conductance and conductivity of specimens of
24、 agglomerated stone products are also included (see Annex C - informative). 2 Normative references Not applicable. 3 Principle The resistance/conductance of an agglomerated stone specimen is evaluated by the measurement of direct current (DC) flow in the specimen under specified conditions by approp
25、riate electrode systems. The resistivity/conductivity shall be calculated from specimen and electrode dimensions and shapes. 4 Terms and definitions and symbols 4.1 insulation resistance = ohm insulation resistance between two electrodes that are in electrical contact with an agglomerated stone spec
26、imen, calculated as the ratio of the direct voltage applied to the electrodes to the total current flowing between them Note 1 to entry: It is dependent upon the shape and size as well as the volume and surface resistance of the specimen. 4.2 surface resistance Rs() surface resistance between two el
27、ectrodes that are in electrical contact with the surface of an agglomerated stone specimen, calculated as the ratio of the direct voltage applied to the electrodes to that portion of the current between them which is primarily distributed on the specimen surface and a thin material layer beneath the
28、 specimen surface Note 1 to entry: Surface conductivity cannot be accurately known, only conventionally, because more or less volume contribution is usually involved in the measurement, depending on the nature of the specimen and environment. 4.3 surface resistivity s() surface resistivity of the ag
29、glomerated stone material, which is calculated as the ratio of the potential gradient parallel to the current direction along its surface to the current per unit width of the surface BS EN 14617-13:2013EN 14617-13:2013 (E) 5 4.4 surface conductivity s (-1) reciprocal of the surface resistivity 4.5 v
30、olume resistance Rv() volume resistance between two electrodes that are in electrical contact with a specimen, calculated as the ratio of the direct voltage applied to the electrodes to that portion of the current between them that flows only through the volume of the specimen 4.6 volume resistivity
31、 v (m) volume resistivity of the agglomerated stone material, which is calculated as the ratio of the potential gradient, parallel to the current direction in the material, to the current density EXAMPLE The charge carriers flow through the specimen, charge flowing in the unit time across the unit s
32、urface area normal to the current direction. 4.7 volume conductivity v(-1m-1= S/m S = siemens) reciprocal of the volume resistivity 5 Sampling and test specimen preparation Sampling is not the responsibility of the test laboratory, unless otherwise agreed. It shall be appropriate to agglomerated sto
33、ne consignment. Whenever possible, the random sampling method shall be used. Test specimens shall, however, be representative of the agglomerated stone sample and can be directly obtained from laboratory moulding and curing according to a detailed procedure (properly described in the test report) an
34、d/or core samples taken “in situ“ and cut to proper size for the measuring apparatus. The surfaces shall be honed or polished. The test specimen may have any practical shape allowing the use of a proper three terminal electrodes system, according to the electrode assembly schematically shown in Figu
35、re 1 for flat test specimens. Sheet specimens like those illustrated in Figure 1 should exhibit a thickness exceeding by 20 % the largest stone fragments size used in the agglomerated stone, and a diameter of 20 mm to 160 mm according to the resistivity of the tested material. At least five test spe
36、cimens shall be selected by sampling. 6 Specimen conditioning Measurements shall be made on either room-conditioned (23 2) C and (50 10) % R.U. or dried specimens. In the first case, specimens shall be measured after proper conditioning (24 h at least) in the measuring environment according to other
37、 existing standard conditioning procedures. In the latter case, specimen should be dried to constant weight in a circulating-air oven at (50 2) C (i.e. difference 4 th g 2 th Key d0 internal diameter of the electrodes th thickness of the specimen g width of the guard gap 1 measuring or guarded elect
38、rode 2 high voltage electrode 3 guard electrode D diameter of the electrodes Figure 1 Three-terminal electrode configuration of measuring surface resistance/conductance BS EN 14617-13:2013EN 14617-13:2013 (E) 9 Key V voltage S specimen E electrometer Rc resistance Figure 2 Voltmeter-ammeter method u
39、sing an electrometer (schematic) BS EN 14617-13:2013EN 14617-13:2013 (E) 10 Annex A (informative) DC electrical conduction and polarisation phenomena in insulating materials Resistivity/conductivity in electrically insulating bodies may be used as an indirect measure of static charging, moisture con
40、tent, mechanical continuity and damages of various types, as well as of the effects of fibres (steel, glass, polymer, etc.), fillers (calcium carbonate, conducting, semiconducting and insulating powders, etc.), cement and polymers content on their properties. Resin addition or cement substitution by
41、 resin in cement bound agglomerated stone products usually results in a remarkable conductivity decrease and may lead to accumulation of electrostatic charges on the body surfaces. Polarised electrostatic charges are dangerous in risk environments, such as in the presence of flammable gases, vapours
42、 and fine powders suspended in air (e.g. sugar, coal, flour, condensed milk, metal) where explosions may take place, in electronic equipments and plants (where blackout can arise), in surgery rooms and annexes (where some kinds of disinfectants and anaesthetics can cause fire and explosions) and sim
43、ilar ones. On the other hand, decrease in conductivity may be favourable where high electrical insulation is required. Measurement of electrical conductivity/resistivity of agglomerated stones proves therefore to be very useful for building and architectural use. Resistivity/conductivity of insulati
44、ng materials depends on temperature, humidity, electrification time and applied voltage. These parameters should be accurately known to make the measured value reliable. In particular, humidity content should be known, as it contributes to electrical conduction processes by releasing protons. The el
45、ectrical behaviour of insulating materials is indeed very different from that of electrically conducting and semiconducting materials. The very low concentration of electronic charge carriers makes electrical conduction to be contributed only by ionic migration and polarised atomic and molecular gro
46、ups vibration and local motion under the external electrical field. These phenomena give rise to electrical conduction processes which greatly depend on time; macroscopic relaxation processes are then revealed by the measurement of transient electrical phenomena as a function of time in bulk materia
47、l. A steady state bulk polarisation in the material can be sketched as in Figure A.1 under a constant electrical field in a common voltmeter-ammeter testing method. It should be noticed that the elementary charge separation depicted in the figure occurs in the material during a time largely dependin
48、g on both the nature of charge carriers and material microstructure, leading to the so-called leakage current Ic after a very long time. Key V voltmeter A ammeter 1 switch position 2 switch position Figure A.1 Electrical polarisation of an electrically insulating material under a constant electrical
49、 field BS EN 14617-13:2013EN 14617-13:2013 (E) 11 Therefore, in principle, the charge flow, and hence the electrical current Ic flowing under an applied electrical voltage V, usually decreases with time as schematically reported in Figure A.2. Due to the contrasting effect of the increasing electrical polarisation within the material, this is the reason why any measurement should always be made at a known time (usually, one or two minutes after the electrical field application). The measured Ict at the meas
