1 Scope
This document specifies the requirements for protection against electrical hazards in the design and manufacture of electrical installations and equipment for rolling stock.
This document applies to rail rolling stock, road transport vehicles powered by external electricity (e.g. trams). Maglev vehicles and equipment on these rolling stock.
This document does not apply to:
Mining railways in mines:
Railway lifting devices, moving platforms and similar transport systems;
Temporary facilities.
This document does not cover the requirements for surface installations in relation to protection against vehicle electrical potential.
2 Normative references
The contents of the following documents constitute essential provisions of this document by means of normative references in the text. Where a reference is dated, only the version corresponding to that date applies to this document; a reference without a date. The latest version (including all the revision sheets) is applicable to this document.
GB/T 4208-2017 Enclosure protection class (IP code) (IEC 60529:2013.1DT)
GB/T 13870.1 Effects of electric currents on humans and domestic animals Part 1: General part (GB/T 13870.1-2008, IEC/TS 60479-1:2005, IDT)
GB/T 16895.21- 2020 Low voltage electrical installations Part 4-41: Safety protection against electric shock (IEC 60364-4-41:2017, IDT)
Note: GB/T 16895.21- 2020 is quoted without technical differences to IEC 60364-41.2005.
GB/T 17045-2020 General part of electric shock protection devices and equipment (IEC 61140:2016, IDT)
3 Terminology. Definitions and abbreviations
3.1 Terminology and definitions
The following terms and definitions apply to this document.
3.1.1 Definitions of persons involved
3.1.1.1
3.1.1.1 Skilled person (electrically) skilled person
A person with the appropriate education and experience. A person who is capable of detecting and avoiding hazards caused by electricity.
[Source: GB/T 2900.73- 2008, 195-04-01. with modifications]
3.1.1.2
Trained (electrical) person (elctrically) instructed person
A person who is adequately instructed or supervised by a skilled electrical technician to detect and avoid hazards caused by electricity.
[Source: GB/T 2900.73- -2008, 195-04-02]
3.1.1.3
Ordinary person
A person who is neither a skilled nor a trained person.
[Source:GB/T 2900.73- 2008.195-04-03. with modifications]
3.1.2 Definitions related to insulation
3.1.3 Other definitions
3.2 Abbreviations
The following abbreviations apply to this document.
4 Classification of voltage classes
4.1 General requirements
In this document, the protective measures that can be applied are based on the highest nominal voltage that the equipment or circuit can withstand.
The voltages are classified according to their nominal values. This is shown in Table 1. Different rules apply to each of these voltage classes.
Rolling stock. The various power supplies on board have different categories, e.g. C11.COlll
4.2 Inter-circuit connections
Connected by power conversion devices with adequate insulation between circuits. Circuits operating at different nominal voltages are classified separately according to the nominal voltage of each of them.
4.3 Exceptions
If the interstage voltage conversion device includes overvoltage detection equipment that enables the primary or secondary circuit to be broken, or other detection equipment that prevents overvoltage in the secondary circuit. It is permitted to classify the secondary circuit according to the maximum operating voltage of the detection device. It is appropriate to assess the integrity of equipment with overvoltage detection as appropriate.
Circuits that are not connected to the vehicle body. For example, floating earth power supplies, are allowed to be classified according to any voltage level. Consideration is given to the possibility of these circuits being subject to various potentials under normal and fault conditions. It is appropriate to choose the appropriate classification. This is to ensure that the requirements of this document are met.
5 Protective measures against direct contact
5.1 General requirements
Electrically charged bodies capable of causing electric shock need to be protected from direct contact and all equipment should be operated with direct contact protection. Direct contact protection shall be provided at least by means of 5.2 or 5.3.
If protection cannot be provided in accordance with 5.2 or 5.3. It is permitted to use voltage class 1 protection in accordance with the conditions of 5.4.
In addition, if adequate protection against direct contact is required... A warning sign as described in 5.5 shall be provided.
5.2 Insulation protection
In addition to the requirements of GB/T 32350.1, the insulation used for live bodies should be in accordance with the rated operating voltage and conditions of use of the equipment. It is advisable to consider further measures to minimise the extent of damage.
5.3 Protection through proximity prevention
5.3.1 Voltage class 1 to class M
5.3.1.1 Protection by means of enclosed electrical operating areas
Electrically charged bodies in rolling stock powered by voltages of class I to class I. They should be placed in an enclosed electrical operating area.
Access shall be prevented by mechanical locking with steps and warning signs appropriate for the enclosed place and equipment.
The measures to prevent access shall comply with the following provisions:
Inside the rolling stock - in areas that are generally accessible to personnel - protective screens and shields shall comply with the protection class IP4X of GB/T 4208-2017, or when they are electrically connected to the vehicle body. They shall comply with the protection class IP2XD of GB/T 4208- 2017. The requirements of this article do not apply to connectors. Lampholders without bulbs. Screw-type fuse sockets without pins.
Where mesh grilles or grid barriers are used, an appropriate distance should be maintained to prevent direct contact due to bending and deformation.
5.3.1.2 Protection for electrically operated areas
5.3.2 Voltage class IN
5.3.2.1 No person, including skilled personnel, should be in close proximity to a Class IV live body using protection in enclosed electrical operating areas.
Trained (electrical) personnel and skilled (electrical) personnel may only approach a live body supplied with voltage class N if one or more of the following methods are used to ensure safety after a power failure:
Measures to prevent access and to make the live body safe shall be in accordance with the following:
The cover of the generally accessible area of the vehicle shall comply with the protection class IP4X of GB/T 4208- -2017. Areas accessible to trained and skilled (electrical) personnel shall comply with the protection class IP2X of GB/T 4208- -2017;
If the Class II voltage is maintained after disconnection of the Class IV live body, direct contact with the Class II live body should be prevented in accordance with 5.3.1.
5.4 Protection with class I voltage (ELV)
5.4.1 Requirements for Class I voltage systems (SELV/PELV)
5.5 Warning signs
Warning signs for electrical hazards shall comply with GB/T 18209.1.
If the presence of an electrical hazard has been confirmed, a warning sign shall be provided to identify the presence of the electrical hazard and provide the necessary additional information necessary to prevent injury to persons after all interlocking devices or design elements have functioned on the approaching equipment. The warning sign should be installed in a suitable location. Ensure that it is clearly visible and remains in place for the lifetime of the equipment.
When the roof of the vehicle may be in close proximity to an electrically charged body in contact with the network. Warning signs should be provided.
Warning signs should be provided in any enclosed electrical operating area containing voltage class Il or voltage class N. Warning signs may not be placed where a locking system is used to ensure that access is prohibited when dangerous voltages are present.
6 Protective measures against indirect contact
6.1 General requirements
Chapter 6 specifies the methods that can be used to bring the vehicle body potential sufficiently close to the potential of the protective conductor at ground level.
The methods described in 6.2 to 6.5 shall ensure that the exposed conductive parts are not subject to electric shock by induction or contact with nearby live bodies under fault conditions, the objective being to ensure that all exposed conductive parts at risk as described above are at the same potential. This can be achieved by means of the protective connection in 6.2 alone or in combination with an automatic cut-off. or by other means as described in 6.5.
The descriptions and exceptions shall be in accordance with 6.5.
Additional requirements shall be in accordance with 6.6.
7 Power circuits
7.1 General requirements
The power circuit shall be designed to ensure that all current flows back to the power supply without causing damage or risk of electric shock to the rolling stock.
Where sliding or flexible connections are used between the car body or bogie and the rails, each unit shall have at least two such independent connection paths and a fault in one of these paths shall not cause damage or a risk of electric shock.
8 Other requirements
8.1 General requirements
Measures shall be taken to ensure the safety of any electrically charged body, which may cause electric shock if disconnected, and to prevent electric shock.
Terms negotiable between supply and demand shall meet the requirements of Appendix B.
Appendix A (Informative) Examples of solutions for impedance management in electric motive units (EMU)
Appendix B (normative) Negotiable terms between supply and demand
References
1 Scope
2 Normative references
3 Terminology. Definitions and abbreviations
4 Classification of voltage classes
5 Protective measures against direct contact
6 Protective measures against indirect contact
7 Power circuits
8 Other requirements
Appendix A (Informative) Examples of solutions for impedance management in electric motive units (EMU)
Appendix B (normative) Negotiable terms between supply and demand
References
