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GB/T 16935.1-2008 PDF in English


GB/T 16935.1-2008 (GB/T16935.1-2008, GBT 16935.1-2008, GBT16935.1-2008)
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GB/T 16935.1-2008: PDF in English (GBT 16935.1-2008)

GB/T 16935.1-2008
Insulation coordination for equipment within low-voltage systems. Part 1. Principles, requirements and tests
ICS 29.120
K30
National Standards of People's Republic of China
GB/T 16935.1-2008/IEC 60664-1..2007
Replacing GB/T 16935.1-1997
Low voltage system equipment with the insulation
Part 1. Principles, requirements and tests
(IEC 60664-1..2007, IDT)
Posted.2008-04-24
2008-12-01 implementation
General Administration of Quality Supervision, Inspection and Quarantine of People's Republic of China
China National Standardization Administration released
Directory
Preface Ⅰ
1 Scope and purpose 1
2 Normative references 1
3 Terms and definitions 2
4 insulation with the basic principles of 7
5 Requirements and rules for sizing 13
6 Tests and measurements 19
Appendix A (Informative) Basic parameters of the tolerance characteristics of the gap 31
Appendix B (Informative) Different over-voltage control of the power supply system nominal voltage 36
Appendix C (Normative) Partial discharge test method 38
Appendix D (Informative) Partial discharge test method Supplementary information 42
Appendix E (informative) Table F. Creepage distance specified in Table 4 and Table A. 1 in the electrical gap comparison 44
Appendix F (Normative) Table 45
References 54
GB/T 16935.1-2008/IEC 60664-1..2007
Foreword
GB/T 16935 "Insulation coordination of equipment in low-voltage systems" is expected to be divided into five parts.
--- Part 1. Principles, requirements and tests;
--- Part 2. Application Guide;
--- Part 3. The use of coating, sealing and molding anti-fouling protection;
--- Part 4. high frequency voltage stress considerations;
--- Part 5. Determination of clearances and creepage distances not exceeding 2mm.
This section identical with IEC 60664-1..2007 "Insulation coordination with low-voltage system equipment Part 1. Principles, requirements and testing."
This standard replaces standard. GB/T 16935.1-1997.
This section compared with GB/T 16935.1-1997, the main technical differences exist.
--- Increased the Japanese grid single-phase system nominal voltage 100V or 100V ~.200V, relates to the rated impulse voltage, rationalization
Voltage and different over-voltage control of the nominal voltage of the power supply system;
--- In Table A 1 increased the tolerance of less than 0.01mm gap characteristics of the basic parameters;
--- Added Table F 7 "Tolerance to steady-state voltage, temporary over-voltage or reproduction of peak voltage clearance";
--- Table F 4 Increases the minimum creepage distance relative to the rms value of 12500V to 63000V;
--- Modify the original Figure 1 "Material Group Ⅰ to determine the size of creepage distances with voltage and pollution level", and as Appendix E
Content, diagram title changed to "creepage distance specified in Table F.4 and Table A.1 electrical clearance comparison";
--- Modify the provisions relating to the creepage of the tendons, an increase of Figure 2 "determine the width and height of the ribs";
--- Modify Table F 5 (formerly titled "Test Voltages for Verification of Clearances at Sea Level") is replaced by "Verification of electrical work at different elevations
Gap test voltage "), an increase of.200m above sea level, 500m at the test voltage value;
--- Modify the original Chapter 4 (now Chapter 6) "Test and Measurement", the test, the purpose of the test and test equipment and possible alternative tests
Described in more detail;
--- The original Appendix A, Appendix B, Appendix D is a normative appendix, now according to IEC into an informative appendix;
--- Deleted and verify the clearance has nothing to do 2U + 1000V for 1min dielectric test;
--- Table F 4 and the original 4.2 (now 6.2) to delete the pollution level 4.
This part of the Appendix C and Appendix F normative appendix, Appendix A, Appendix B, Appendix D and Appendix E is an informative annex.
This part is proposed by China Electrical Equipment Industry Association.
This part of the National Standardization Technical Committee of low-voltage electrical (SAC/TC189) centralized.
This section is responsible for drafting unit. Shanghai Electric Institute of Science (Group) Co., Ltd..
Participated in the drafting of this section. Hang Shen Holdings Group Co., Ltd., Zhejiang Delixi Electric Co., Ltd., Zhejiang Chint Electric shares
Limited, Schneider Electric (China) Investment Co., Ltd.
The main drafters of this section. Huang Jingye, Wu Qingyun, Li Hui.
Participate drafters of this section. He Guibing, Huang Rongrong, Ye Sufeng, Zhang Ping.
This part of the standard replaces the previous editions are. GB/T 16935.1-1997.
GB/T 16935.1-2008/IEC 60664-1..2007
Low voltage system equipment with the insulation
Part 1. Principles, requirements and tests
1 Scope and purpose
GB/T 16935 provisions of this part of the low-voltage system equipment insulation coordination, this section applies to altitude to.2000m, rated power
Pressure to 1000V, rated frequency to 30kHz or DC to 1500V equipment.
According to the equipment performance standards, this part of the provisions of the equipment clearances, creepage distances and solid insulation requirements. This part of the package
Including the insulation with the electrical test methods.
The minimum electrical clearance specified in this section does not apply to have ionized gas Department. Special requirements for this situation can be met by the corresponding product
Standard Technical Committee to deal with their own products.
This section does not involve determining the following distances.
--- through the liquid insulation;
--- Pass gas other than air;
--- By compressed air.
Note 1. Insulation coordination of equipment within the low-voltage system of rated frequency above 30kHz according to IEC 60664-4.
Note 2. The internal circuitry of the device may exhibit higher voltages.
Note 3. The guidelines for determining the size above.2000m above sea level are shown in Table A. 2.
This section is the basic electrical safety standards, designed to guide the technical committee responsible for product standards for its various equipment responsible for the development of
The requirements, to achieve the purpose of insulation.
This section for each product standard technical committee to determine the equipment in the air gap, creepage distance and solid insulation provided the necessary
Guidance information.
Manufacturers and product standards Technical Committee has the responsibility to apply the requirements of the basic safety standards, if necessary, standard equipment
Cite these requirements.
If the relevant product standard does not specify the values of clearances, creepage distances and the requirements for solid insulation, or in the absence of standards
Under this section applies.
2 Normative references
The following documents contain provisions which, through the reference in this part of GB/T 16935.1, become the provisions of this section. Any reference to date
Documents, all subsequent Amendments (not including errata content) or revisions do not apply to this section, however, this section is encouraged to promote
The parties to the agreement study whether the latest versions of these documents are available. For undated references, the latest version applies to this book
section.
GB 156-2003 standard voltage (neqIEC 60038-1983)
GB/T 1408.1-2006 Insulating materials electrical strength test methods - Part 1. Test under power frequency (idt IEC 60243-1.
1998)
GB/T 2421-1999 Environmental testing for electric and electronic products Part 1. General (idt IEC 60068-1. 1988)
GB/T 2423.2-2001 Environmental testing for electric and electronic products Part 2. Test methods Test B. High temperature (idt IEC
60068-2-2. 1974)
GB/T 2423.3-2006 Environmental testing for electric and electronic products Part 2. Test methods Test Cab. constant hot and humid test
(Idt IEC 60068-2-78..2001)
GB/T 2423.22-2002 Basic environmental testing for electric and electronic products Part 2. Test methods Test N. Temperature change
GB/T 16935.1-2008/IEC 60664-1..2007
(Idt IEC 60068-2-14. 1984)
GB/T 2900.5-2002 Electrotechnical terminology Insulating solids, liquids and gases (eqv IEC 60050 (212)..1990)
GB/T 2900.57-2002 Electrotechnical terminology Generation, transmission and distribution operations (eqv IEC 60050 (604). 1987)
GB/T 4207-2003 solid insulating materials in comparison with the damp conditions of the tracking index and resistance to tracking index
(Idt IEC 60112. 1979)
GB/T 7354-2003 partial discharge measurement (idt IEC 60270..2000)
GB/T 11021-1989 Thermal insulation and classification of electrical insulation (eqv IEC 60085. 1984)
GB/T 16499-1996 Guidelines for the preparation of electrical safety standards (IEC Guide 104. 1984)
GB/T 17045-2006 Shock protection devices and equipment common part (idt IEC 61140..2001)
GB/T 17627.1-1998 high voltage test techniques for low voltage electrical equipment - Part 1. Definitions and test requirements (eqv IEC
61180-1..1992)
GB/T 17627.2-1998 high voltage test techniques for low voltage electrical equipment Part II. Measurement systems and test equipment
(Eqv IEC 61180-2..1994)
IEC 60050 (151)..2001 International Electrotechnical Vocabulary (IEV) Chapter 151 Electrical and magnetic devices
IEC 60050 (826)..2004 International Electrotechnical Vocabulary (IEV) Chapter 826. Electrical installations
IEC 60085..2004 Electrical insulation - Thermal classification
Surge arresters - Part 1. Gap valve surge arresters for ac systems
IEC 60112..2003 Solid insulating materials compared to the tracking under the dawning index and tracking resistance index method
IEC 60216 (all parts) Electrical Insulation Materials Heat Resistance
IEC 60364-4-44..2001 Electrical installations of buildings - Part 4-44. Safety protection Voltage disturbances and protection against electromagnetic interference
Amendment 1 (2003)
IEC 60664-4..2005 Insulation coordination of equipment in low voltage systems - Part 4. Considerations for high frequency voltage stress
IEC 60664-5..2007 Insulation coordination of equipment in low-voltage systems - Part 5. Clearances and creepage distances up to 2 mm
Determination of distance 1)
IEC Guide 104..1997 Preparation of Safety Publications and Applications of Basic Safety and Professional Safety Publications
3 Terms and definitions
1) The new version of IEC 60664-5 (2nd edition) quoted by IEC 60664-1..2007 at the time of publication has not yet been published and is now published in July.2007.
This section uses the following definition.
3.1
The interdependence of the insulation properties of electrical equipment is considered in the context of the expected micro-environment and other effects.
Note. According to the characteristics specified in 3.5 to 3.7 to represent the expected voltage stress.
3.2
The shortest distance between two conductive parts in the air.
3.3
The shortest distance between two conductive parts along the solid insulating material surface.
(IEV151-15-50)
3.4
Solid insulating material inserted between two conductive parts.
GB/T 16935.1-2008/IEC 60664-1..2007
3.5
The maximum rms value of ac voltage or d.c. voltage that may be generated at any given insulation across the equipment at rated voltage.
Note 1. Does not consider the transient phenomenon.
Note 2. Both open and normal operation should be considered.
3.6
The maximum peak value at which the voltage waveform is periodically shifted due to the AC voltage distortion or due to the AC component superimposed on the DC voltage
Voltage.
Note. Random overvoltages (eg due to over-voltage due to occasional operation) are not considered to reproduce the peak voltage.
3.7
Any voltage that peaks above the corresponding peak of the maximum steady-state voltage during normal operation.
3.7.1
Power overvoltage that lasts for a relatively long time (corresponding to instantaneous overvoltage).
3.7.2
Oscillatory or non-oscillating, usually high-damping short duration overvoltages of only a few milliseconds or less.
(IEV604-03-13)
3.7.3
Instantaneous overvoltage that occurs at any point in the system due to a specific on-off operation or fault continuity.
3.7.4
Due to a specific lightning discharge, transient overvoltages occur anywhere in the system.
3.7.5
For the function of the appliance, a conscious application of overvoltage.
3.8
The voltage applied to the sample under the specified test conditions does not cause breakdown and/or flashover of the sample.
(IEV212-01-31)
3.8.1
Under specified conditions, does not cause insulation breakdown, with a certain shape and polarity of the peak value of the impact voltage.
3.8.2
Under specified conditions, does not cause insulation breakdown of the maximum RMS voltage.
3.8.3
Under specified conditions, does not cause the breakdown voltage of the highest peak voltage.
GB/T 16935.1-2008/IEC 60664-1..2007
3.8.4
Under specified conditions, does not cause insulation breakdown of the maximum transient over-voltage value.
3.9
The manufacturer's specified voltage level for components, appliances or equipment, which is related to characteristics such as operation (including operation) and performance.
Note. The equipment may have more than one rated voltage or may have a rated voltage range.
3.9.1
The manufacturer's tolerance voltage rating of the equipment or its components to characterize the (long-term) resistance of their insulation.
Note. The rated insulation voltage is not necessarily equal to the rated voltage of the equipment. The rated voltage is mainly related to the operation of equipment.
3.9.2
The manufacturer's specified impulse withstand voltage values for the equipment or parts thereof to characterize the insulation's ability to withstand transient overvoltages.
3.9.3
The manufacturer specifies the equipment or its components to reproduce the peak withstand voltage value to characterize the insulation withstand voltage
ability.
3.9.4
Manufacturer's temporary tolerance to equipment or its components overvoltages to characterize the short-term withstand voltage capability of their insulation.
3.10
Use numbers to describe transient overvoltage conditions.
Note 1. Overvoltage category I, II, III and IV, see 4.3.3.2.
Note 2. The term "overvoltage category" is synonymous with "shock-tolerant category" used in 443 of IEC 60364-4-44.
3.11
Any combination of foreign substances (solids, liquids, or gases) that reduce the electrical strength and surface resistivity of insulation.
3.12
Surroundings that may affect the performance of the device or system.
Note. such as pressure, temperature, humidity, pollution, radiation and vibration.
(IEV151-16-03, modified)
3.12.1
Equipment installation or use of the room or other places of the environment.
3.12.2
In particular, it will affect the environment near the insulation that determines the size of the creepage distance.
3.13
Digital representation of the micro-environment by the expected degree of pollution.
Note. Pollution levels are indicated by 1, 2, 3 and 4, see 4.6.2.
GB/T 16935.1-2008/IEC 60664-1..2007
3.14
For example, the radius of each ball between two balls is greater than the electric field (uniform electric field) with a substantially constant voltage gradient across the electrodes
Electric field from the distance.
Note. Uniform electric field conditions are referred to as Case B.
3.15
The voltage gradient between the electrodes is not substantially constant (non-uniform electric field).
Note. The worst-case non-uniform electric field conditions for the tip-to-planar electrode structure with regard to voltage tolerance are referred to as Case A. It can be made by one
A spot electrode with a radius of 30 μm and a plane electrode of 1 m × 1 m.
3.16
Expected within the electrical system transient over-voltage is limited to the required level conditions.
3.17
Electrical products used to separate conductive parts with different potentials.
(IEV212-01-05)
3.17.1
The conductive parts are only suitable for the insulation required for the specific function of the equipment.
3.17.2
Set on hazardous live parts to provide basic protection of the insulation.
Note. This concept does not apply to insulation specifically for functional purposes.
(IEV826-12-14)
3.17.3
In addition to the basic insulation used for fault protection, separate insulation is additionally provided.
(IEV826-12-15)
3.17.4
Insulation consisting of both basic and additional insulation.
(IEV826-12-16)
3.17.5
Set on hazardous live parts, providing insulation equal to the degree of electrical shock protection of double insulation.
Note. Reinforced insulation may have multiple layers, and these levels can not be tested individually with or without basic insulation.
(IEV826-12-17)
3.18
PD
Part of the bridge insulation discharge at both ends.
GB/T 16935.1-2008/IEC 60664-1..2007
3.18.1
The charge that can be measured at the test terminal.
Note 1. Apparent charge is less than the partial discharge.
Note 2. The apparent charge requirement requires a short circuit condition at the test terminal (see D.2).
3.18.2
The amount of apparent charge as a limit under this section.
Note. The maximum pulse should be calculated.
3.18.3
The apparent number of pulses per second that is greater than the measured level.
Note. In the context of this section, pulse repetition rate is not allowed to estimate the discharge.
3.18.4
Ui
When the test voltage rises higher than the lower limit of the discharge did not occur, while the apparent charge is greater than the specified minimum discharge test voltage peak.
Note. For the exchange test, available RMS.
3.18.5
Ue
When the test voltage drops below the upper limit of discharge, and the apparent charge is less than the specified minimum discharge test voltage peak.
Note. For the exchange test, available RMS.
3.18.6
Ut
Test voltage peak value used in 6.1.3.5.3 Test procedure in which the apparent charge is less than the specified discharge capacity.
Note. For the exchange test, available RMS.
3.19
In accordance with established procedures, technical operations to determine one or more characteristic values for a given product, process or service.
(ISO /IEC Guide 2..1996, 13.1) 2)
NOTE - The characteristics or properties of an entity are measured or classified by applying a set of environmental and operating conditions and/or testing to an entity.
(IEV151-16-13)
3.19.1
A test of one or more appliances manufactured according to a design to demonstrate that the design complies with certain specifications.
3.19.2
Each appliance is manufactured and/or post-manufactured to determine if it meets certain criteria.
2) References in square brackets refer to references.
GB/T 16935.1-2008/IEC 60664-1..2007
3.19.3
A number of electrical appliances randomly selected from a number of tests carried out.
3.20
When the discharge is completely bridged, insulation fails under electrical stress, causing the voltage drop across the electrodes to approach zero.
3.20.1
Electrical breakdown in gas or liquid media.
3.20.2
Electrical breakdown along a solid insulating surface in a gas or liquid medium.
3.20.3
Electrical breakdown through solid insulation.
4 insulation with the basic principles
4.1 Overview
Insulation coordination means that the electrical insulation characteristics of the equipment are chosen according to the use of the equipment and its surrounding environment.
Insulation coordination can only be achieved if the design of the equipment is based on the stresses (eg voltage) that it experiences during its expected lifetime.
4.2 on the voltage with the insulation
4.2.1 Overview
The following should be considered.
--- Voltage that may appear in the system;
--- Equipment generated voltage (the voltage may in turn affect other devices in the system);
--- Required continuous operation level;
--- personal and property safety, voltage stress may cause accidents can not lead to unacceptable risk of damage.
4.2.2 For long-term exchange or DC voltage insulation coordination
Long-term voltage insulation is mainly based on.
--- Rated voltage;
--- Rated insulation voltage;
---Operating Voltage.
4.2.3 on the transient over-voltage insulation coordination
The transient over-voltage insulation coordination is mainly based on controlled over-voltage conditions. There are two main controls.
--- Internal control. Requirements of electrical system characteristics can be expected to transient over-voltage limit conditions at the required level;
--- Protection Control. Requirements specified in the electrical system over-voltage attenuation measures can be expected to transient over-voltage limit at the required level
condition.
NOTE 1 Overvoltages in large and complex systems such as low-voltage power systems, which may be affected by many and varied factors, can only be determined based on
Statistical method to assess, this method is particularly useful for over-voltage generated by the atmosphere, both for internal control or through the protection and control to achieve
Controlled conditions also apply.
NOTE 2 It is advisable to use probability analysis to assess whether there is inherent control or if protection controls are required. This analysis requires knowledge of the characteristics of the electrical system, lightning strikes
Level, instantaneous overvoltage level and so on. This method has been used by IEC 60364-4-44 in building electrical installations connected to low voltage power systems.
NOTE 3 Specific overvoltage decay measures may be devices with energy storage and dissipation measures that can be used to harmlessly consume expected locations under specified conditions
GB/T 16935.1-2008/IEC 60664-1..2007
Voltage energy.
In order to apply the concept of insulation coordination, the following two sources of transient overvoltage must be distinguished.
--- From the system of transient over-voltage, the system is connected with the terminal equipment;
--- Instantaneous over-voltage generated by the device itself.
Insulation coordination with the rated impulse voltage preferred values are as follows.
330V, 500V, 800V, 1500V, 2500V, 4000V, 6000V, 8000V, 12000V.
4.2.4 on the reproduction of peak voltage insulation coordination
Partial discharges that may occur within solid insulation (see 5.3.2.3.1) or partial discharges that may occur along an insulating surface shall be considered (see table
F. 7b).
4.2.5 on the temporary over-voltage insulation coordination
Insulation coordination for temporary overvoltages The temporary overvoltages specified in 442 of IEC 60364-4-44 (see 5.3.3.2.3 of this part) are
basis.
Note. Current surge protectors (SPDs) do not adequately absorb the energy generated by temporary overvoltages.
4.2.6 on the environmental conditions of the insulation coordination
The microscopic environmental conditions of insulation should be considered with quantified pollution levels.
The micro-environmental conditions mainly depend on the macroscopic environmental conditions in which the equipment is located. In many cases, these micro- and macro-environments are the same
of. However, the micro-environment may be better or worse than the macro environment. For example, housings, heating, ventilation or dust may affect the microenvironment.
Note. Enclosures with electrical ratings according to IEC 60529 [2] may not require any improvement in the microenvironment associated with contamination.
The most important environmental parameters are as follows.
--- For the electrical clearance.
● pressure,
● temperature, if the change is large;
--- For the creepage distance.
● pollution,
● relative humidity,
● condensation effect;
--- For solid insulation.
● temperature,
● Relative humidity.
4.3 Voltage and its rating
4.3.1 Overview
In order to determine the size of the insulating structure of the equipment according to the insulation coordination, each product standard technical committee shall provide.
--- Basic voltage rating;
--- According to the intended use of the device overvoltage category provisions, the need to consider the expected system characteristics and equipment connected.
4.3.2 long-term role in the determination of voltage
4.3.2.1 Overview
Set the rated voltage of the device not lower than the nominal voltage of the power system.
4.3.2.2 determine the basic insulation voltage
4.3.2.2.1 Equipment powered directly from the low-voltage network
Table F. 3a and Table F 3b (see 5.2.2.2) has been the nominal voltage of low-voltage power grid into a rationalization voltage, the voltage can be used as
The minimum creepage distance voltage can also be used to select the rated insulation voltage of the equipment.
The electrical equipment can have several rated voltages so that it can be used in low voltage networks with different nominal voltages. Such equipment voltages should be chosen
The highest rated voltage.
GB/T 16935.1-2008/IEC 60664-1..2007
Each product standard technical committee should consider how to choose the voltage.
--- Based on "line to line" voltage; or
--- Based on "line to neutral" voltage.
In the latter case, the technical committee of the product standard should specify how the user should be informed that the device can only be used in a neutral earthing system.
4.3.2.2.2 Systems, equipment and internal circuits not directly fed by the low-voltage network
The basic insulation in systems, equipment and internal circuits should take into account the highest possible RMS voltages that may be present. The voltage to determine the test
Consider the nominal voltage of the power supply and the worst combination of other conditions within the rating range of the equipment.
Note. The fault conditions are not considered.
4.3.2.3 to determine the function of insulation voltage
The actual operating voltage can be used to determine the size required for functional insulation.
4.3.3 Determination of the rated impulse voltage
4.3.3.1 Overview
Instantaneous over-voltage can be used as a basis for determining the rated impulse voltage.
4.3.3.2 Overvoltage category
4.3.3.2.1 Overview
Equipment powered directly from the low-voltage network is subject to the concept of overvoltage category.
Overvoltage categories have a probabilistic meaning and do not refer to the physical attenuation of transient overvoltages in downstream equipment.
Note 1. This overvoltage category concept has been adopted by IEC 60364-4-44.
Note 2. The term "overvoltage category" is synonymous with "Shock Tolerance Category" used in 443 of IEC 60364-4-44.
A similar concept applies to devices that connect other systems (such as telecommunications and data systems).
4.3.3.2.2 Equipment powered directly by the grid
Each product standard technical committee shall determine the overvoltage category based on the following basic description of the overvoltage category
IEC 60335-4-44 443).
--- Overvoltage category Ⅳ equipment is used in the power distribution equipment, power equipment;
Note 1. Such devices include such as measuring instrument and the former over-current protection device.
--- Overvoltage category Ⅲ equipment is a fixed distribution equipment in the equipment, as well as the reliability and suitability of equipment must meet the special
Demanding
NOTE 2 Such equipment includes switchgear installed in fixed distribution units and industrial installations permanently connected to fixed distribution units.
--- Overvoltage category Ⅱ equipment is powered by a fixed power distribution device energy equipment;
Note 3. Such devices include appliances, portable tools and other household and similar payloads.
If the reliability and suitability of such equipment have special requirements, the overvoltage category III shall apply.
--- Overvoltage Category I devices are connected to the device with a circuit that limits the transient overvoltage to a reasonably low level.
These measures should ensure that the temporary over-voltage generated can be sufficiently limited and the peak value can not exceed Table F. 1 in the relevant rated impact
Voltage.
Note 4. Such equipment contains equipment such as protection of electronic circuits to achieve this level, see 4.2.5 Note.
Note 5. Except when the circuit is designed to temporarily over-voltage, or overvoltage category I equipment can not be directly connected to the grid.
4.3.3.2.3 Systems and equipment not directly powered by a low-voltage network
Where appropriate, it is recommended that each product standard technical committee specify overvoltage ca......
 
Source: Above contents are excerpted from the PDF -- translated/reviewed by: www.chinesestandard.net / Wayne Zheng et al.