prEN IEC 61340-4-7:2022

Electrostatics - Part 4-7: Standard test methods for specific applications - Ionization

This part of IEC 61340 provides test methods and procedures for evaluating and selecting air ionization equipment and systems (ionizers). This document establishes measurement techniques, under specified conditions, to determine offset voltage (ion balance) and decay (charge neutralization) time for ionizers. This document does not include measurements of electromagnetic interference (EMI), or the use of ionizers in connection with ordnance, flammables, explosive items or electrically initiated explosive devices. As contained in this document, the test methods and test conditions can be used by manufacturers of ionizers to provide performance data describing their products. Users of ionizers are urged to modify the test methods and test conditions for their specific application in order to qualify ionizers for use, or to make periodic verifications of ionizer performance. The user will decide the extent of the data required for each application. See Annex A for information regarding theoretical background and additional information on the standard test method for the performance of ionizers. CAUTION: Procedures and equipment described in this document can expose personnel to hazardous electrical and non-electrical conditions. Users of this document are responsible for selecting equipment that complies with applicable laws, regulatory codes and both external and internal policy. Users are cautioned that this document cannot replace or supersede any requirements for personnel safety. See Annex C for safety considerations.

Elektrostatik - Teil 4-7: Standard-Prüfverfahren für spezielle Anwendungen – Ionisation

Electrostatique - Partie 4-7: Méthodes d'essai normalisées pour des applications spécifiques - Ionisation

Elektrostatika - 4-7. del: Standardne preskusne metode za posebno uporabo - Ionizacija

General Information

• Status: Not Published
• Publication Date: 30-Oct-2023
• ICS: 17.200.99 - Other standards related to thermodynamics
• ICS: 29.020 - Electrical engineering in general
• Technical Committee: CLC/SR 101 - Electrostatics
• Drafting Committee: IEC/TC 101 - IEC_TC_101
• Current Stage: 4060 - Enquiry results established and sent to TC, SR, BTTF - Enquiry
• Start Date: 01-Jul-2022
• Completion Date: 01-Jul-2022
• Ref Project: oSIST prEN IEC 61340-4-7:2022 - Electrostatics - Part 4-7: Standard test methods for specific applications - Ionization

Relations

• Revises: EN 61340-4-7:2017 - Electrostatics - Part 4-7: Standard test methods for specific applications - Ionization
• Effective Date: 27-Apr-2021

Standards Content (Sample)

SLOVENSKI STANDARD
oSIST prEN IEC 61340-4-7:2022
01-junij-2022
Elektrostatika - 4-7. del: Standardne preskusne metode za posebno uporabo -
Ionizacija

Electrostatics - Part 4-7: Standard test methods for specific applications - Ionization

Elektrostatik - Teil 4-7: Standard-Prüfverfahren für spezielle Anwendungen – Ionisation

Electrostatique - Partie 4-7: Méthodes d'essai normalisées pour des applications
spécifiques - Ionisation
Ta slovenski standard je istoveten z: prEN IEC 61340-4-7:2022
ICS:
17.220.99 Drugi standardi v zvezi z Other standards related to
elektriko in magnetizmom electricity and magnetism
oSIST prEN IEC 61340-4-7:2022 en

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN IEC 61340-4-7:2022
101/650/CDV
COMMITTEE DRAFT FOR VOTE (CDV)
PROJECT NUMBER:
IEC 61340-4-7 ED3
DATE OF CIRCULATION: CLOSING DATE FOR VOTING:
2022-04-08 2022-07-01
SUPERSEDES DOCUMENTS:
101/629/CD, 101/635A/CC
IEC TC 101 : ELECTROSTATICS
SECRETARIAT: SECRETARY:
Germany Mr Hartmut Berndt
OF INTEREST TO THE FOLLOWING COMMITTEES: PROPOSED HORIZONTAL STANDARD:
Other TC/SCs are requested to indicate their interest, if any,
in this CDV to the secretary.
FUNCTIONS CONCERNED:
EMC ENVIRONMENT QUALITY ASSURANCE SAFETY

SUBMITTED FOR CENELEC PARALLEL VOTING NOT SUBMITTED FOR CENELEC PARALLEL VOTING

Attention IEC-CENELEC parallel voting
The attention of IEC National Committees, members of
CENELEC, is drawn to the fact that this Committee Draft for
Vote (CDV) is submitted for parallel voting.
The CENELEC members are invited to vote through the
CENELEC online voting system.

This document is still under study and subject to change. It should not be used for reference purposes.

Recipients of this document are invited to submit, with their comments, notification of any relevant patent rights of which they

are aware and to provide supporting documentation.
TITLE:

Electrostatics - Part 4-7: Standard test methods for specific applications - Ionization

PROPOSED STABILITY DATE: 2027
NOTE FROM TC/SC OFFICERS:

Copyright © 2022 International Electrotechnical Commission, IEC. All rights reserved. It is permitted to download this

electronic file, to make a copy and to print out the content for the sole purpose of preparing National Committee positions.

You may not copy or "mirror" the file or printed version of the document, or any part of it, for any other purpose without

permission in writing from IEC.
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1 CONTENTS

2 FOREWORD ........................................................................................................................... 4

3 INTRODUCTION ..................................................................................................................... 6

4 1 Scope .............................................................................................................................. 7

5 2 Normative references ...................................................................................................... 7

6 3 Terms and definitions ...................................................................................................... 7

7 4 Test fixture and instrumentation ....................................................................................... 9

8 5 Specific requirements for equipment categories ............................................................. 11

9 5.1 Specific requirements for all ionization equipment ................................................. 11

10 5.2 Room ionization .................................................................................................... 12

11 5.3 Laminar flow hood ionization ................................................................................. 14

12 5.4 Work surface ionization ......................................................................................... 16

13 5.5 Compressed gas ionizers – Guns and nozzles ...................................................... 19

14 Annex A (informative) Theoretical background and additional information on the

15 standard test method for the performance of ionizers ............................................................ 21

16 A.1 Introductory remarks ............................................................................................. 21

17 A.2 Air ions ................................................................................................................. 21

18 A.3 Mobility and ion current ......................................................................................... 21

19 A.4 Neutralization current ............................................................................................ 21

20 A.5 Neutralization rate ................................................................................................ 22

21 A.6 Ion depletion and field suppression ....................................................................... 22

22 A.7 Charged plate monitor and charge neutralization .................................................. 22

23 A.8 Relationship between charged plate monitor decay time and actual object ............ 23

24 A.9 Offset voltage ....................................................................................................... 23

25 A.10 Preparation of test area ........................................................................................ 23

26 A.11 Ion transport in airflow .......................................................................................... 24

27 A.12 Obstruction of airflow around the charged plate monitor ........................................ 24

28 A.13 Effect of “air blanket” ............................................................................................ 24

29 A.14 Sources of measurement error .............................................................................. 25

30 A.14.1 Typical decay time variability ......................................................................... 25

31 A.14.2 Plate isolation ................................................................................................ 25

32 A.14.3 Charging voltage ........................................................................................... 25

33 A.14.4 Materials near the plate ................................................................................. 25

34 A.14.5 Other field-producing devices in test area ...................................................... 25

35 A.14.6 Effect of offset voltage on decay time ............................................................ 25

36 A.15 Importance of ionization equipment maintenance .................................................. 26

37 Annex B (normative) Method of measuring the capacitance of an isolated conductive

38 plate ..................................................................................................................................... 27

39 B.1 Method ................................................................................................................. 27

40 B.2 Equipment ............................................................................................................ 27

41 B.3 Procedure ............................................................................................................. 27

42 B.4 Example................................................................................................................ 28

43 B.5 Sources of error .................................................................................................... 28

44 B.5.1 Measuring equipment .................................................................................... 28

45 B.5.2 Poor plate isolation ........................................................................................ 29

46 B.5.3 Objects in the environment ............................................................................ 29

47 B.5.4 Stray capacitance .......................................................................................... 29

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48 Annex C (informative) Safety considerations ........................................................................ 30

49 C.1 General ................................................................................................................. 30

50 C.2 Electrical ............................................................................................................... 30

51 C.3 Ozone ................................................................................................................... 30

52 C.4 Radioactive ........................................................................................................... 30

53 C.5 X-ray ..................................................................................................................... 30

54 C.6 Installation ............................................................................................................ 30

55 Bibliography .......................................................................................................................... 30

57 Figure 1 – Charged plate monitor components for non-contacting plate measurement .......... 10

58 Figure 2 – Charged plate monitor components for contacting plate measurement ................. 10

59 Figure 3 – Conductive plate detail for the non-contacting CPM ............................................. 11

60 Figure 4 – Conductive plate detail for the voltage follower CPM ............................................ 11

61 Figure 5 – Test locations for room ionization – AC grids and DC bar systems ....................... 13

62 Figure 6 – Test locations for room ionization – Single polarity emitter systems ..................... 13

63 Figure 7 – Test locations for room ionization – Dual DC line systems .................................... 14

64 Figure 8 – Test locations for room ionization – Pulsed DC emitter systems ........................... 14

65 Figure 9 – Test locations for vertical laminar flow hood – Top view ....................................... 15

66 Figure 10 – Test locations for vertical laminar flow hood – Side view .................................... 15

67 Figure 11 – Test locations for horizontal laminar flow hood – Top view ................................. 16

68 Figure 12 – Test locations for horizontal laminar flow hood – Side view ................................ 16

69 Figure 13 – Test locations for benchtop ionizer – Top view ................................................... 17

70 Figure 14 – Test locations for benchtop ionizer – Side view .................................................. 18

71 Figure 15 – Test locations for overhead ionizer – Top view ................................................... 18

72 Figure 16 – Test locations for overhead ionizer – Side view .................................................. 19

73 Figure 17 – Test locations for compressed gas ionizer (gun or nozzle) – Side view ............... 20

75 Table 1 – Test set-ups and test locations/points (TP) ............................................................ 12

76 Table B.1 – Example measurement data ............................................................................... 28

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79 INTERNATIONAL ELECTROTECHNICAL COMMISSION
80 ____________
82 ELECTROSTATICS –
84 Part 4-7: Standard test methods for specific applications –
85 Ionization
88 FOREWORD

89 1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising

90 all national electrotechnical committees (IEC National Committees). The object of IEC is to promote international

91 co-operation on all questions concerning standardization in the electrical and electronic fields. To this end and

92 in addition to other activities, IEC publishes International Standards, Technical Specifications, Technical Reports,

93 Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC Publication(s)”). Their

94 preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with

95 may participate in this preparatory work. International, governmental and non-governmental organizations liaising

96 with the IEC also participate in this preparation. IEC collaborates closely with the International Organization for

97 Standardization (ISO) in accordance with conditions determined by agreement between the two organizations.

98 2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international

99 consensus of opinion on the relevant subjects since each technical committee has representation from all

100 interested IEC National Committees.

101 3) IEC Publications have the form of recommendations for international use and are accepted by IEC National

102 Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC

103 Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any

104 misinterpretation by any end user.

105 4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications

106 transparently to the maximum extent possible in their national and regional publications. Any divergence between

107 any IEC Publication and the corresponding national or regional publication shall be clearly indicated in the latter.

108 5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity

109 assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any

110 services carried out by independent certification bodies.

111 6) All users should ensure that they have the latest edition of this publication.

112 7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and

113 members of its technical committees and IEC National Committees for any personal injury, property damage or

114 other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and

115 expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC

116 Publications.

117 8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is

118 indispensable for the correct application of this publication.

119 9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of patent

120 rights. IEC shall not be held responsible for identifying any or all such patent rights.

121 International Standard IEC 61340-4-7 has been prepared by IEC technical committee 101:

122 Electrostatics.

123 This third edition cancels and replaces the second edition, published in 2010, and constitutes

124 a technical revision.

125 This edition includes the following significant technical changes with respect to the previous

126 edition:

127 – A reference to Annex A was added for regarding theoretical background and additional

128 information on the standard test method for the performance of ionizers.

129 – NOTE 3, Figure 5 as added to clarify for AC bars and grids a single emitter alternating

130 between +/- polarity is used.

131 – Updated Annex B relative error for measurement equipment to include the consideration for

132 the resolution of the voltmeter
133
134
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135 The text of this standard is also based on the following documents:
FDIS Report on voting
101/xxx/FDIS 101/xxx/RVD
136

137 Full information on the voting for the approval of this standard can be found in the report on

138 voting indicated in the above table.

139 This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.

140 A list of all parts in the IEC 61340 series, published under the general title Electrostatics, can

141 be found on the IEC website.

142 The committee has decided that the contents of this publication will remain unchanged until the

143 stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to

144 the specific publication. At this date, the publication will be
145 • reconfirmed,
146 • withdrawn,
147 • replaced by a revised edition, or
148 • amended.
149
150
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151 INTRODUCTION

152 Grounding is the primary method used to limit static charge when protecting electrostatic

153 discharge sensitive items in the work environment. However, grounding methods are not

154 effective in removing static charges from the surfaces of non-conductive (insulative) or isolated

155 (ungrounded) conductive materials. Air ionization techniques, by means of ionizer systems, can

156 be utilized to reduce this charge.

157 The preferred way of evaluating the ability of an ionizer to neutralize a static charge is to directly

158 measure the rate of charge decay. Charges to be neutralized may be located on insulators as

159 well as on isolated conductors. It is difficult to charge an insulator reliably and repeatably.

160 Charge neutralization is more easily evaluated by measuring the rate of decay of the voltage of

161 an isolated conductive plate. The measurement of this decay should not interfere with or change

162 the nature of the actual decay. Four practical methods of air ionization are addressed in this

163 document:
164 a) radioactive emission;
165 b) high-voltage corona from a.c. electric fields;
166 c) high-voltage corona from d.c. electric fields;
167 d) soft X-ray emission.

168 This part of IEC 61340 provides test methods and procedures that can be used when evaluating

169 ionization equipment. The objective of the test methods is to generate meaningful, reproducible

170 data. The test methods are not meant to be a recommendation for any particular ionizer

171 configuration. The wide variety of ionizers, and the environments within which they are used,

172 will often require test methods different from those described in this document. Users of this

173 document should be prepared to adapt the test methods as required to produce meaningful data

174 in their own application of ionizers.

175 Similarly, the test conditions chosen in this document do not represent a recommendation for

176 acceptable ionizer performance. There is a wide range of item sensitivities to static charge.

177 There is also a wide range of environmental conditions affecting the operation of ionizers.

178 Performance specifications should be agreed upon between the user and manufacturer of the

179 ionizer in each application. Users of this document should be prepared to establish reasonable

180 performance requirements for their own application of ionizers.

181 Annex B provides a method for measuring capacitance of the isolated conductive plate.

182
183
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184 ELECTROSTATICS –
185
186 Part 4-7: Standard test methods for specific applications –
187 Ionization
188
189
190
191 1 Scope

192 This part of IEC 61340 provides test methods and procedures for evaluating and selecting air

193 ionization equipment and systems (ionizers).

194 This document establishes measurement techniques, under specified conditions, to determine

195 offset voltage (ion balance) and decay (charge neutralization) time for ionizers.

196 This document does not include measurements of electromagnetic interference (EMI), or the

197 use of ionizers in connection with ordnance, flammables, explosive items or electrically initiated

198 explosive devices.

199 As contained in this document, the test methods and test conditions can be used by

200 manufacturers of ionizers to provide performance data describing their products. Users of

201 ionizers are urged to modify the test methods and test conditions for their specific application

202 in order to qualify ionizers for use, or to make periodic verifications of ionizer performance. The

203 user will decide the extent of the data required for each application.

204 See Annex A for information regarding theoretical background and additional information on the

205 standard test method for the performance of ionizers.

206 CAUTION: Procedures and equipment described in this document can expose personnel to hazardous electrical and

207 non-electrical conditions. Users of this document are responsible for selecting equipment that complies with

208 applicable laws, regulatory codes and both external and internal policy. Users are cautioned that this document

209 cannot replace or supersede any requirements for personnel safety. See Annex C for safety considerations.

210 2 Normative references

211 IEC 6101-1, Safety requirements for electrical equipment for measurement, control, and

212 laboratory use – Part 1
213 3 Terms and definitions

214 For the purposes of this document, the following terms and definitions apply.

215 ISO and IEC maintain terminological databases for use in standardization at the following

216 addresses:
217 • IEC Electropedia: available at http://www.electropedia.org/
218 • ISO Online browsing platform: available at http://www.iso.org/obp
219 3.1
220 air conductivity

221 ability of air to conduct (pass) an electric current under the influence of an electric field

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222 3.2
223 air ions

224 molecular clusters of about ten molecules (water, impurities, etc.) bound by polarization forces

225 to a singly charged oxygen or nitrogen molecule
226 3.3
227 charge decay
228 decrease and/or neutralization of a net electrostatic charge
229 3.4
230 charged plate monitor
231 CPM

232 instrument using a charged metal plate of a defined capacitance and geometry which is

233 discharged in order to measure charge dissipation/neutralization properties of products or

234 materials
235 Note 1 to entry: This note applies to the French language only.
236 3.5
237 compressed gas ionizer

238 ionization device that can be used to neutralize charged surfaces and/or remove surface

239 particles with pressurized gas

240 Note 1 to entry: This type of ionizer may be used to ionize the gas within production equipment.

241 3.6
242 corona

243 production of positive or negative ions by a very localized high electric field

244 Note 1 to entry: The field is normally established by applying a high voltage to a conductor in the shape of a sharp

245 point or wire.
246 3.7
247 decay time

248 time necessary for a voltage (due to an electrostatic charge) to decay from an initial value to

249 some chosen final value
250 3.8
251 emitter

252 conducting sharp object, usually a needle or wire, which will cause a corona discharge when

253 kept at a high potential
254 3.9
255 horizontal laminar flow
256 non-turbulent airflow in a horizontal direction
257 3.10
258 ionizer
259 device designed to generate positive and/or negative air ions
260 3.11
261 isolated conductor
262 non-grounded conductor
263 3.12
264 laminar flow hood ionization

265 device or systems that provide local area ionization coverage in vertical or horizontal laminar

266 flow hoods or benches
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267 3.13
268 non-contacting voltage measurement

269 measurement technique using an electrostatic fieldmeter or voltmeter to monitor the voltage

270 induced on an isolated conductive plate where there is no direct connection from the

271 measurement sensor to the isolated conductive plate
272 3.14
273 offset voltage
274 ion balance

275 observed voltage on the isolated conductive plate of a charged plate monitor (CPM) that has

276 been placed in an ionized environment
277 3.15
278 peak offset voltage

279 for pulsed ionizers, maximum value of the offset voltage for each polarity, as the ionizer cycles

280 between positive and negative ion outputs
281 3.16
282 room ionization
283 ionization systems that provide large area coverage with air ions
284 3.17
285 work surface ionization

286 ionization devices or systems used to control static charges at a work surface

287 Note 1 to entry: This type includes benchtop ionizers, overhead work surface ionizers and laminar flow hood

288 ionizers.
289 3.18
290 vertical laminar flow
291 non-turbulent airflow in a vertical direction
292 3.19
293 contacting voltage measurement

294 measurement technique using high input impedance circuitry used to monitor the voltage induced on

295 an isolated conductive plate where there is a direct connection from the circuitry to the conductive

296 plate
297 4 Test fixture and instrumentation

298 The instrument described in this document to make performance measurements on air

299 ionization equipment is the charged plate monitor (CPM); refer to Figure 1 and Figure 2. The

300 conductive plate shall be (15,0 ± 0,1) cm × (15,0 ± 0,1) cm and the total capacitance of the test

301 circuit, with plate, while the instrument is in its normal operating mode, shall be 20 pF ± 2 pF

302 (refer to Annex B). See Figure 3 and Figure 4. The instrument described in this document may

303 also be used for compliance verification of air ionizers.

304 For the isolated conductive plate design shown in Figure 3, there shall be no objects, grounded

305 or otherwise, closer than dimension "A" of the conductive plate, except the supporting insulators

306 or plate voltage contacts, as shown in Figure 3 (refer to Annex B). For the conductive plate

307 assembly shown in Figure 4, there shall be no objects, grounded or otherwise, within 2,5 cm of

308 the plate assembly in any direction, other than a support structure (e.g. a tripod) located below

309 the ground plate of the assembly.

310 The conductive plate, when charged to the desired test voltage, shall not decay more than 10 %

311 of the test voltage within 5 min, in the absence of ionization.
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312 The voltage on the conductive plate shall be monitored in such a way that the system conforms

313 to 4.1, 4.2 and 4.3. The response time of the monitoring device shall be sufficient to accurately

314 measure changing plate voltages. Changing plate voltages are a function of the ionization

315 technology type being monitored.

316 For safety reasons (see Clause C.1), the voltage source used to charge the plate should be

317 current limited.
Probe
See NOTE
Switch
Conductive plate
Insulator
Ground plate
Ground
High voltage
power supply -
current limited
Non-contacting
voltmeter or
electrometer
Decay timer
318
319 NOTE See Figure 3.

320 Figure 1 – Charged plate monitor components for non-contacting plate measurement

+HV
Threshold
A/D detector and
decay timer
20pF –HV
–HV +HV
IEC
321
322 Figure 2 – Charged plate monitor components for contacting plate measurement
323
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(15,0 ± 0,1) cm × (15,0 ± 0,1) cm
C d ti l t
Dimension A
User defined
Insulator
Ground plate
Ground
≥ 15 IEC
324
325 Figure 3 – Conductive plate detail for the non-contacting CPM
(15,0 ± 0,1) cm × (15,0 ± 0,1) cm
C d ti l t bl
Insulator
Driven shield
Insulator
Ground plate
15 IEC
326
327 Figure 4 – Conductive plate detail for the voltage follower CPM
328 5 Specific requirements for equipment categories
329 5.1 Specific requirements for all ionization equipment

330 For the types of ionization equipment listed in 5.2, 5.3, 5.4 and 5.5, the following specific

331 requirements apply:

332 a) Decay time test – The conductive plate of the test fixture shall be charged to an initial test

333 voltage and allowed to decay to 10 % of the initial test voltage. The time required shall be

334 monitored and recorded for both polarities of initial charge (refer to 4.1 and Figure 1).

335 b) Offset voltage test – The conductive plate shall be momentarily grounded to remove any

336 residual charges and to verify zero of the voltage monitoring device. The plate is then

337 monitored within the ionized environment, per the procedure described for each equipment

338 category. The resulting observed voltage is referred to as the offset voltage.

339 c) Locations – The decay time and offset voltage shall be measured and recorded for each

340 tes
...