High-Voltage Alternating-Current Disconnectors and Earthing Switches
1 General
1.1 Scope
This standard applies to the alternating-current disconnectors and earthing switches with enclosed or open terminals, designed for indoor and outdoor electric power systems of voltages above and including 3.0 kV and 50Hz service frequencies. It also applies to the operating devices of these disconnectors and earthing switches and their auxiliary equipment.
Additional requirements for the disconnectors and earthing switches in enclosed switchgear and controlgear are given in GB 3906-2006, GB 7674-2008 and IEC 62271-201:2003.
Note: disconnectors in which the fuse forms an integral part are not covered by this standard.
1.2 Normative References
The following documents are indispensable for the application of this standard. For dated references, only the dated edition is applicable to this document. For undated references, the latest editions of the normative documents (including all the amendments) are applicable to this document.
GB/T 772 Technical Specifications of Porcelain Element for High Voltage Insulators
GB/T 1804 General Tolerances-Tolerances for Linear and Angular Dimensions without Individual Tolerance Indications (GB/T 1804-2000, eqv ISO 2768-1:1989)
GB/T 2900.20-1994 Electrotechnical Terminology-High-voltage Switchgear [IEC 60050 (IEV): 1984, NEQ]
GB 3804-2004 High-voltage Alternating-current Switches for Rated Voltage above 3.6kV and less than 40.5kV (IEC 60265-1: 1998, MOD)
GB 3906-2006 Alternating-current Metal-enclosed Switchgear and Controlgear for Rated Voltages above 3.6 kV and up to and including 40.5 kV (IEC 62271-200:2003, MOD)
GB/T 4109 Insulated Bushings for Alternating Voltages above 1 000V (GB/T 4109-2008, IEC60137, MOD)
GB 4208 Degrees of Protection Provided by Enclosure (IP Code) (GB 4208-2008, IEC 60529: 2001, IDT)
GB/T 5273 Terminals for Transformers, High-voltage Apparatus and Bushings (GB/T 5273-1985, IEC 60518: 1975, NEQ)
GB/T 5582 External Insulation Pollution Classes of High-voltage Electric Power Equipments (GB/T 5582-1993, IEC 60507: 1991, NEQ)
GB/T 7354 Partial Discharge Measurements (GB/T 7354-2003, IEC 60270: 2000, IDT)
GB 7674-2008 Gas-insulated Metal-enclosed Switchgear for Rated Voltages of 72.5kV and above (IEC 62271-203: 2003, MOD)
GB/T 8287.1 Indoor and Outdoor Post Insulators for Systems with Nominal Voltage Greater than 1000 V - Part 1: Test on Insulators of Ceramic Material or Glass (IEC 60815-1:2002, MOD)
GB/T 8287.2 Indoor and Outdoor Post Insulators for Systems with Nominal Voltage Greater than 1000 V - Part 2: Dimensions and Characteristics (IEC60815-2:2002, MOD)
GB/T 11022 Common Specifications for High-voltage Switchgear and Controlgear Standards
GB/T 13540 Seismic Qualification for High-voltage Switchgear and Controlgear (GB/T 13540-2009, IEC 62271-2:2003, MOD)
GB/T 14810 AC High Voltage Switches for Rated Voltages of 110kV and above (GB/T 14810-1993, IEC 60265-2:1988, NEQ)
DL/T 593-2006 Common Specifications for High-voltage Switchgear and Controlgear Standards (IEC 60694:2002, MOD)
IEC 62271-201:2003 AC Insulation-enclosed Switchgear and Controlgear for Rated Voltages above 1kV and up to and including 38kV
IEC 62271-203:2003 Gas-insulated Metal-enclosed Switchgear and Controlgear for Rated Voltages above 72.5kV
IEC 60865-1:1993 Short-circuit Currents - Calculation of Effects - Part 1: Definitions and Calculation Methods
2 Normal and Special Service Conditions
Chapter 2 of DL/T 593-2006 is applicable.
3 Terms and Definitions
Chapter 3 of DL/T 593-2006 is applicable with the following additions:
3.1 General Terms
3.1.101
Indoor switchgear and controlgear
The switchgear and controlgear that can only be used in the buildings or other shelters where they can be protected from the effects of wind, rain, snow, ice, frost, condensation, and deposited dust, etc.
3.1.102
Outdoor switchgear and controlgear
The switchgear and controlgear that can be used in the open air where they can endure the effects of wind, rain, snow, ice, frost, condensation, and deposited dust, etc.
3.1.103
Temperature rise (of a part of a disconnector or earthing switch)
Difference between the temperature of the part and the ambient air temperature
3.1.104
User
Person or legal entity using the disconnectors or earthing switches
Note: this may include the purchaser (for example an electricity supplier), but it may also include the contracting company, the staff responsible for installation, the maintenance or operating staff or anybody else temporarily or permanently responsible for the disconnector, earthing switch or substation, or even the operation of the switchgear.
3.2 Assemblies of Switchgear and Controlgear
No particular definitions.
3.3 Parts of Assemblies
No particular definitions.
3.4 Switching Devices
3.4.101
Disconnector
In the open position, there shall be specified insulation distance and obvious disconnecting marks between contacts; in the closed position, there shall be switchgear that can bear the current under normal circuit conditions and the current under abnormal conditions (e.g. short circuit) within specified time. In the case of "negligible current" in the circuit or "no significant change in voltage" between two terminals of each pole in disconnector before and after opening and closing, disconnector shall have the capacity of opening and closing the circuits.
Note 1: "Negligible current" implies currents such as the capacitive currents of bushings, busbars, connections, very short lengths of cable, currents of permanently connected grading impedances of circuit-breakers and currents of voltage transformers and dividers. For rated voltages of 363 kV and below, a current not exceeding 0.5 A is a negligible current for the purpose of this definition; for rated voltage of 550 kV and above, currents exceeding 0.5 A, the manufacturer shall be consulted. "No significant change in voltage" refers to such applications as the by-passing of induction voltage regulators or circuit-breakers.
Note 2: for a disconnector having a rated voltage of 72.5 kV and above, a rated ability of bus-transfer current switching may be assigned.
3.4.101.1
Disconnector class MO
Disconnector having a mechanical endurance of 1 000 operating cycles, suitable for applications in distribution and transmission systems fulfilling the general requirements of this standard
3.4.101.2
Disconnector class M1
Disconnector having an extended mechanical endurance of 3000 or 5000 operating cycles, mainly for applications where the disconnector is operated in conjunction with a circuit-breaker of an equal class
3.4.101.3
Disconnector class M2
Disconnector having an extended mechanical endurance of 10 000 operating cycles, mainly for applications where the disconnector is operated in conjunction with a circuit-breaker of an equal class
3.4.102
Single-column disconnector (earthing switch)
Disconnector having fixed contact of each pole hung on busbar or independent support, moving contact supported by independent base or frame, and fracture vertical or parallel to the base plane, e.g. one-arm vertical folding disconnector, double-arm vertical folding disconnector
3.4.103
Double-column disconnector
Disconnector having two horizontal-turn contacts supported by independent knob insulators on each pole, moving and fixed contacts contacting in the middle of two columns, and fracture direction parallel to the base plane; or disconnector having fixed contact fixed on one porcelain knob, moving contact capable of vertical turn, and fracture at a certain vertical angle with the base plane
3.4.104
Three-column disconnector
Disconnector having three sets of knob insulators on each pole, horizontal-turn moving contact as the intermediate column, two mutual-tandem fractures, and fracture direction parallel to the base plane
3.4.105
Earthing switch
Section 3.28 of GB/T 2900.20-1994 is applicable with the following addition:
Note: an earthing switch having a rated voltage of 72.5 kV and above may have a rating for switching and carrying induced currents.
Classes E1, E2 and E3 of GB 3804-2004 are based on the electrical endurance of load switches and switch-disconnectors. These devices may sometimes be operated against a short-circuit as a normal operation duty and the electrical endurance may be the measure of "low maintenance“.
3.4.105.1
Earthing switch class E0
Earthing switch suitable for applications in distribution and transmission systems fulfilling the general requirements of this standard
3.4.105.2
Earthing switch class E1
Earthing switch class E0 with a short-circuit making capability
Note: this class of earthing switch is able to withstand two making operations at rated making current.
3.4.105.3
Earthing switch class E2
Earthing switch class E1 requiring minimal maintenance, capable of an extended number of short-circuit making operations suitable for applications in systems up to and including 35 kV
Contents
Foreword i
1 General
1.1 Scope
1.2 Normative References
2 Normal and Special Service Conditions
3 Terms and Definitions
3.1 General Terms
3.2 Assemblies of Switchgear and Controlgear
3.3 Parts of Assemblies
3.4 Switching Devices
3.5 Parts of Switching Devices
3.6 Operation
3.7 Characteristic Quantities
4 Ratings
4.1 Rated Voltage (Ur)
4.2 Rated Insulation Level
4.3 Rated Frequency (fr)
4.4 Rated Current and Temperature Rise
4.5 Rated Short-time Withstand Current (Ik)
4.6 Rated Peak Withstand Current (Ip)
4.7 Rated Duration of Short-circuit (tk)
4.8 Rated Supply Voltage of Closing and Opening Devices and of Auxiliary and Control Circuits (Ua)
4.9 Rated Supply Frequency of Closing and Opening Devices and of Auxiliary and Control Circuits
4.10 Rated Pressure OF Compressed Gas Supply of Controlled Pressure System
4.11 Rated Filling Level of Gas or Liquid for Insulation and/or Operation
4.101 Rated Short-circuit Making Current
4.102 Rated Contact Zone
4.103 Rated Mechanical Terminal Load
4.104 Rated Values of the Bus-Transfer Current Switching Capability of Disconnectors
4.105 Rated Values of the Induced Current Switching Capability of Earthing Switches
4.106 Rated Values of the Bus-Charging Current Switching Capability of Disconnectors
4.107 Rated Values of Mechanical Endurance for Disconnectors and Earthing Switches
4.108 Rated Values of Electrical Endurance for Earthing Switches
4.109 Rated Values of the Small Inductive Current Switching Capability of Disconnectors
5 Design and Construction
5.1 Requirements for Liquids in Disconnectors and Earthing Switches
5.2 Requirements for Gases in Disconnectors and Earthing Switches
5.3 Earthing of Disconnectors and Earthing Switches
5.4 Auxiliary and Control Equipment
5.5 Dependent Power Operation
5.6 Stored Energy Operation
5.7 Independent Manual Operation
5.8 Operation of Releases
5.9 Low- and high-pressure Interlocking and Monitoring Devices
5.10 Nameplates
5.11 Interlocking Devices
5.12 Position Indication
5.13 Degree of Protection by Enclosures
5.14 Creepage Distances
5.15 Gas and Vacuum Tightness
5.16 Liquid Tightness
5.17 Flammability
5.18 Electromagnetic Compatibility (EMC)
5.19 X-ray Radiation
5.20 Corrosion
5.101 Special Requirements for Earthing Switches
5.102 Requirements in Respect of the Isolating Distance of Disconnectors
5.103 Mechanical Strength
5.104 Operation of Disconnectors and Earthing Switches– Position of the Movable Contact System and Its Indicating and Signaling Devices
5.105 Maximum Force Required for Manual Operation
5.106 Dimensional Tolerances
5.107 Requirements for the Machine Driven Systems and Conduction Circuits
5.108 Requirements for the Porcelain Support Insulators and Operation Insulators of Disconnectors and Earthing Switches
5.109 Requirements for the Two-pole or Three-pole Disconnector Operated by the Same Operating Device
6 Type Tests
6.1 General
6.2 Dielectric Tests
6.3 Radio Interference Voltage (r. i. v) Test
6.4 Measurement of the Resistance of Circuits
6.5 Temperature-rise Tests
6.6 Short-time Withstand Current and Peak Withstand Current Tests
6.7 Verification of the Protection
6.8 Tightness Tests
6.9 Electromagnetic Compatibility Tests (EMC)
6.10 Additional Tests on Auxiliary and Control Circuits
6.11 X-ray Test Procedures of Vacuum Breaking Device
6.101 Test to Prove the Short-circuit Making Capacity of Earthing Switches
6.102 Operating, Mechanical Endurance and Interlock Function Tests
6.103 Operation under Severe Ice Conditions
6.104 Operation at the Temperature Limits
6.105 Tests to Verify the Proper Functioning of the position indicating device
6.106 Bus-transfer Current Switching Capability Tests of Disconnectors
6.107 Induced Current Switching Capability Tests of Earthing Switches
6.108 Bus-charging Current Switching Capability Tests of Disconnectors
6.109 Small Inductive Current Switching Capability Tests of Disconnectors
6.110 Pressure Withstand Tests of Enclosures
6.111 Internal Fault Arcing Tests
6.112 Shock Tests
7 Routine Tests
7.1 Dielectric Test on the Main Circuit
7.2 Dielectric Test on Auxiliary and Control Circuits
7.3 Measurement of the Resistance of the Main Circuit
7.4 Tightness Test
7.5 Design and Visual Checks
7.6 Mechanical Operation and Mechanical Characteristic Tests
8 Guide to the Selection of Disconnectors and Earthing Switches
8.101 General
8.102 Selection of Rated Values for Normal Service Conditions
9 Information to Be Given with Enquiries, Tenders and Orders
9.101 Information to Be Given with Enquiries and Orders
9.102 Information to Be Given with Tenders
10 Rules for Transport, Storage, Installation, Operation and Maintenance
10.1 Conditions during Transport, Storage and Installation
10.2 Installation
10.3 Operation
10.4 Maintenance
11 Safety
11.1 Electrical Aspects
11.2 Mechanical Aspects
11.3 Thermal Aspects
11.4 Operation Aspects
12 Influences of Product on Environment
Annex A (Normative) Design and Testing of Position Indicating Devices
Annex B (Normative) Bus-Transfer Current Switching by Disconnectors
Annex C (Normative) Induced Current Switching by Earthing Switches
Annex D (Informative) Test Voltage for the Most Disadvantageous Dielectric Position of an Earthing Switch during Operation (Temporary Approach)
Annex E (Normative) Special Requirements for Disconnectors and Earthing Switches Used in Gas-Insulated and/or Metal-Enclosed Switchgear
Annex F (Normative) Gas-Insulated Metal-Enclosed Switchgear for Rated Voltages 77.5 Kv and above – Requirements for Switching of Bus-Charging Currents by Disconnectors
Annex G (Informative) Rated Insulation Level of Disconnector for the Neutral Earthing of Transformer
Annex H (Normative) Technical Specifications of the Porcelain Insulators for High-voltage Alternating-current Disconnectors and Earthing Switches
