1、BSI Standards PublicationMeasurement of DC magnetic, AC magnetic and AC electric fields from 1 Hz to 100 kHz with regard to exposure of human beingsPart 1: Requirements for measuring instrumentsBS EN 61786-1:2014National forewordThis British Standard is the UK implementation of EN 61786-1:2014. It i
2、sidentical to IEC 61786-1:2013.The UK participation in its preparation was entrusted to Tech-nical Committee GEL/106, Human exposure to low frequency and high frequency electromagnetic radiation.A list of organizations represented on this committee can be obtained onrequest to its secretary.This pub
3、lication does not purport to include all the necessary provisions ofa contract. Users are responsible for its correct application. The British Standards Institution 2014.Published by BSI Standards Limited 2014ISBN 978 0 580 74538 6ICS 17.220.20Compliance with a British Standard cannot confer immunit
4、y fromlegal obligations.This British Standard was published under the authority of theStandards Policy and Strategy Committee on 30 April 2014.Amendments/corrigenda issued since publicationDate Text affectedBRITISH STANDARDBS EN 61786-1:2014EUROPEAN STANDARD EN 61786-1 NORME EUROPENNE EUROPISCHE NOR
5、M March 2014 CENELEC European Committee for Electrotechnical Standardization Comit Europen de Normalisation Electrotechnique Europisches Komitee fr Elektrotechnische Normung CEN-CENELEC Management Centre: Avenue Marnix 17, B - 1000 Brussels 2014 CENELEC - All rights of exploitation in any form and b
6、y any means reserved worldwide for CENELEC members. Ref. No. EN 61786-1:2014 E ICS 17.220.20 English version Measurement of DC magnetic, AC magnetic and AC electric fields from 1 Hz to 100 kHz with regard to exposure of human beings - Part 1: Requirements for measuring instruments (IEC 61786-1:2013)
7、 Mesure de champs magntiques continus et de champs magntiques et lectriques alternatifs dans la plage de frquences de 1 Hz 100 kHz dans leur rapport lexposition humaine - Partie 1: Exigences applicables aux instruments de mesure (CEI 61786-1:2013) Messung von magnetischen Gleichfeldern und von elekt
8、rischen und magnetischen Wechselfeldern von 1 Hz bis 100 kHz im Hinblick auf die Exposition von Personen - Teil 1: Anforderungen an Messgerte (IEC 61786-1:2013) This European Standard was approved by CENELEC on 2014-01-16. CENELEC members are bound to comply with the CEN/CENELEC Internal Regulations
9、 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.
10、 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.
11、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 Neth
12、erlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. BS EN 61786-1:2014EN 61786-1:2014 - 2 - Foreword The text of document 106/292/FDIS, future edition 1 of IEC 61786-1, prepared by IEC TC 106, Methods for the assessment of electr
13、ic, magnetic and electromagnetic fields associated with human exposure“ was submitted to the IEC-CENELEC parallel vote and approved by CENELEC as EN 61786-1:2014. The following dates are fixed: latest date by which the document has to be implemented at national level by publication of an identical n
14、ational standard or by endorsement (dop) 2014-10-16 latest date by which the national standards conflicting with the document have to be withdrawn (dow) 2017-01-16 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
15、 shall not be held responsible for identifying any or all such patent rights. Endorsement notice The text of the International Standard IEC 61786-1:2013 was approved by CENELEC as a European Standard without any modification. In the official version, for Bibliography, the following notes have to be
16、added for the standards indicated: IEC 62110:2009 NOTE Harmonised as EN 62110:2009 (not modified). ISO 80000-1:2009 NOTE Harmonised as EN ISO 80000-1:2013 (not modified). ISO/IEC 17025:2005 NOTE Harmonised as EN ISO/IEC 17025:2005 (not modified). BS EN 61786-1:2014- 3 - EN 61786-1:2014 Annex ZA (nor
17、mative) 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 und
18、ated 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 61000-3-2 - Electromagnetic compa
19、tibility (EMC) - Part 3-2: Limits - Limits for harmonic current emissions (equipment input current l), where f is the frequency of the field, c is the speed of light, and l is a characteristic dimension of the measurement geometry, e.g. the distance between the field source and the measurement point
20、 Note 1 to entry: Power frequency magnetic and electric fields near power lines and appliances are examples of quasi-static fields. 3.3.4 resultant field field given by the expression FFFF222R=zyx+ (3) where Fx, Fy, and Fzare the rms values of the three orthogonal field components, or by the express
21、ion FFF2min2maxR+= (4) where Fmax and Fminare the rms values of the semi-major and semi-minor axes of the field ellipse, respectively. Note 1 to entry: The resultant FRis always Fmax. If the field is linearly polarized, Fmin= 0 and FR= Fmax. If the field is circularly polarized, Fmax= Fmin and FR 1,
22、41 Fmax. 3.4 Measurements 3.4.1 correction factor numerical factor by which the uncorrected result of a measurement is multiplied to compensate for a known error Note 1 to entry: Since the known error cannot be determined perfectly, the compensation cannot be complete. 3.4.2 coverage factor numerica
23、l factor used as a multiplier of the combined standard uncertainty in order to obtain an expanded uncertainty Note 1 to entry: For a quantity z described by a normal distribution with expectation zand standard deviation , the interval z k encompasses 68,27 %, 95,45 % and 99,73 % of the distribution
24、for a coverage factor k = 1, 2 and 3, respectively. 3.4.3 scale factor factor by which the instrument reading is multiplied to obtain its input quantity 3.4.4 standard uncertainty uncertainty of the result of a measurement expressed as a standard deviation BS EN 61786-1:201461786-1 IEC:2013 11 3.4.5
25、 uncertainty of calibration parameter, associated with the result of a calibration, that characterizes the dispersion of the values that could reasonably be attributed to the measurand Note 1 to entry: Uncertainty of calibration generally comprises many components. Some of these components may be es
26、timated on the basis of the statistical distribution of the results of series of measurements, and can be characterized by experimental standard deviations. Estimates of other components can be based on experience or other information. 4 Symbols a = radius of coil probe; radius of spherical electric
27、 field probe 2a, 2b = side dimensions of rectangular coil B = magnetic flux density vector B0= amplitude of alternating magnetic field BR= resultant magnetic field Bz= axial magnetic flux density C = stray capacitance of coil probe d = spacing of parallel plates; distance from electromagnetic field
28、source; spacing of Helmholtz coils D = electric displacement vector E = electric field strength E0= uniform electric field strength Fmax, Fmin= rms values of semi-major and semi-minor axes of field ellipse I = current to magnetic field coils L = inductance of coil probe N = number of turns of wire (
29、magnetic field coil system) Q = induced charge r = distance between magnetic field source and measurement location; resistance of coil probe and leads R = approximate input impedance of detector circuit (magnetic field meter); radius of Helmholtz coils S = electrode surface area (electric field mete
30、r) t = time T = period of periodic signal V = voltage Z = impedance in current injection circuit = wave length 0= permittivity of free space 0= permeability of free space = magnetic flux = angular frequency of alternating field BS EN 61786-1:2014 12 61786-1 IEC:2013 5 Instrumentation specifications
31、5.1 General When measuring field in the context of assessment of human exposure, the following items are considered below: measurement of the resultant field strength; measurement of the unperturbed electric field. NOTE 1 Other items may be required depending on the goal of the measurement. The vari
32、ous types of instrumentation available for characterizing quasi-static magnetic fields are described in Clause D.1. The various types of instrumentation available for characterizing static magnetic fields are described in Clause D.3 Several types of magnetic field meters are in common use, e.g. fiel
33、d meters with coil probes, meters with Hall-effect probes, and meters that combine two coils with a ferromagnetic core as in a fluxgate magnetometer. NOTE 2 Hall effect probes respond to static as well as time-varying magnetic flux densities. Due to limited sensitivity and saturation problems someti
34、mes encountered when attempting to measure small power frequency flux densities in the presence of the substantial static geomagnetic flux of the earth, Hall-effect probes have seldom been used to measure magnetic fields of a.c. power lines. The various types of instrumentation available for charact
35、erizing quasi-static electric fields are described in Clause E.1. The following two types of electric field meters are considered in this standard: a) the free-body meter; b) the ground reference meter. Sufficient information shall be provided with the instrumentation, including instrument specifica
36、tions and a clearly written instruction manual, to enable users to determine compliance with this standard, to aid them in the proper operation of the field meter, and to assess the usefulness of the device for the users application. The instrument specifications that shall be provided and/or satisf
37、ied are given below. 5.2 Measurement uncertainty The measurement uncertainty of the measuring instrument shall be specified by the manufacturer of the instrument. The measurement uncertainty shall be determined following the ISO/IEC Guide 98-3. The uncertainty shall be specified as an extended measu
38、rement uncertainty using a coverage factor of 2. The uncertainty is valid after available correction factors are applied. The uncertainty shall contain all components which are relevant when the instrument is used in a nearly uniform field. Such components may be calibration uncertainty, frequency r
39、esponse, deviations of the gain in different measurement range settings, isotropy of the probe, internal noise sources, non-linearity, stability, temperature response and humidity response. The uncertainty of the instrument does not include effects due to the handling of the instrument like position
40、ing the probe in a non-uniform field or the influence of the measuring person on the field to be measured. Such components must be taken into account as additional uncertainties in the measurement report. NOTE 1 At power frequency, the uncertainty of measuring instrument is usually 10 % or better. N
41、OTE 2 Examples of guidelines on the treatment of calibration uncertainties are given in Annex B. BS EN 61786-1:201461786-1 IEC:2013 13 5.3 Magnitude range The magnitude range over which the instrument operates within the specified uncertainty shall be clearly indicated. 5.4 Pass-band Broadband measu
42、ring instruments in the AC range always have a lower and an upper cut off frequency, which define a pass band. Normally the pass band limits are defined by the minus 3 dB point of the frequency response. The nominal frequency response of an instrument can be described as the frequency response of a
43、system with a high pass filter and a low pass filter connected in series. The filter types and the filter orders should be specified (e.g. 3rd order Butterworth high pass and 5thorder Butterworth low pass). The nominal frequency response of the instrument is normally not treated as a source of measu
44、rement uncertainty because the band limiting effect of the filters is a desired property of the instrument if broadband measurements are made. In frequency selective measurements (e.g. FFT) the band limiting effect of the filters is not desired and the nominal frequency response should be automatica
45、lly corrected. The measurement uncertainty of an instrument due to manufacturing tolerances is normally greater at the band limits compared to medium frequencies. Therefore the measurement uncertainty of an instrument is often specified also and sometimes only in a restricted frequency range. This r
46、ange is not as broad as the pass band but should be still broad enough to cover all frequencies of interest. In the restricted frequency range the influence of the nominal frequency response shall be negligible. 5.5 Operating temperature and humidity ranges The temperature and relative humidity rang
47、es over which the instrument operates within the specified uncertainty shall be at least -10 C to 45 C and 5 % to 95 %, respectively. Sudden temperature changes that can lead to condensation in the instrument should be avoided. Electric field measurement may be perturbed if the relative humidity is
48、more than 70 % due to condensation effect on the probe and support 2 1. Since the effect of humidity depends on the field meter, the ability of the field meter to work correctly under those conditions should be checked before measurement (see Annex F). 5.6 Power supplies The use of measurement equip
49、ment that is operating on internal battery power is recommended. If batteries are used, provision should be made to indicate whether the battery condition is adequate for proper operation of the field meter. Instruments used to record personal exposure should be capable of at least 8 h operation within their rated uncertainty before replacement or recharging of the batteries becomes necessary. If rechargeable batteries are used it is recommended that the instrumentation is not operated while connected to the chargin
