Complete switchgears and transformer substations. Transformer substations and distribution devices, their classification and diagrams. Switchgears and substations

4.2.81. Indoor switchgears and substations can be located either in free-standing buildings or be built-in or attached. The extension of a substation to an existing building using the building wall as a substation wall is permitted provided that special measures are taken to prevent damage to the waterproofing of the joint during settlement of the attached substation. The specified settlement must also be taken into account when attaching equipment to an existing building wall.

For additional requirements for the construction of built-in and attached substations in residential and public buildings, see Chapter. 7.1.

4.2.82. In the premises of 35-220 kV closed switchgear and in closed transformer chambers, it is necessary to provide stationary devices or the possibility of using mobile or inventory lifting devices for mechanization of repair work and Maintenance equipment.

In rooms with switchgear, a platform should be provided for repair and adjustment of withdrawable elements. The repair site must be equipped with facilities for testing switch drives and control systems.

4.2.83. Closed switchgears of different voltage classes, as a rule, should be placed in separate rooms. This requirement does not apply to transformer substations of 35 kV and below, as well as switchgear.

It is allowed to place a switchgear up to 1 kV in the same room with a switchgear above 1 kV, provided that parts of the switchgear or substation up to 1 kV and above will be operated by one organization.

The rooms of switchgear, transformers, converters, etc. must be separated from service and other auxiliary rooms (for exceptions, see Chapter 4.3, 5.1 and 7.5).

4.2.84. When assembling GIS in an indoor switchgear, service platforms must be provided at different levels if they are not supplied by the manufacturer.

4.2.85. Transformer rooms and indoor switchgear are not allowed to be placed:

1) under production premises with wet technological process, under showers, bathtubs, etc.;

2) directly above and below the premises, in which, within the area occupied by the switchgear or transformer rooms, more than 50 people can be present at the same time. for a period of more than 1 hour. This requirement does not apply to transformer rooms with dry transformers or with non-flammable filling, as well as switchgear for industrial enterprises.

4.2.86. The clear distances between bare current-carrying parts of different phases, from bare live parts to grounded structures and fences, floor and ground, as well as between bare current-carrying parts of different circuits must be no less than the values given in Table. 4.2.7 (Fig. 4.2.14-4.2.17).

Flexible busbars in closed switchgear should be checked for their convergence under the influence of short-circuit currents in accordance with the requirements of 4.2.56.

4.2.87. The distances from the moving contacts of the disconnectors in the off position to the busbar of its phase connected to the second contact must be at least AND according to table 4.2.7 (see Fig. 4.2.16).

4.2.88. Non-insulated live parts must be protected from accidental touches (placed in chambers, fenced with nets, etc.).

When placing non-insulated live parts outside the chambers and positioning them below the size D according to table 4.2.7 they must be protected from the floor. The height of the passage under the fence must be at least 1.9 m (Fig. 4.2.17).

Live parts located above the fences up to a height of 2.3 m from the floor must be located from the plane of the fence at the distances given in Table. 4.2.7 for size IN(see Fig. 4.2.16).

Devices in which the lower edge of the porcelain (polymer material) of the insulators is located above the floor level at a height of 2.2 m or more are allowed not to be fenced if the above requirements are met.

The use of barriers in fenced cells is not permitted.

Rice. 4.2.14. The smallest clear distances between non-insulated current-carrying parts of different phases in an indoor switchgear and between them and grounded parts (according to Table 4.2.9)

Rice. 4.2.15. The shortest distances between non-insulated live parts in an indoor switchgear and solid fences (according to Table 4.2.9)

Rice. 4.2.16. The shortest distances from non-insulated live parts in the closed switchgear to mesh fencing and between unprotected non-insulated current-carrying parts of different circuits (according to Table 4.2.9)

Rice. 4.2.17. The shortest distances from the floor to unfenced uninsulated

current-carrying parts and to the lower edge of the porcelain insulator and the height of the passage into the closed switchgear. The shortest distance from the ground to unfenced linear outputs from the closed switchgear

outside the territory of the outdoor switchgear and in the absence of transport passage under the outlets

4.2.89. Unguarded, uninsulated leading parts of various circuits located at a height exceeding the size D according to table 4.2.7 must be located at such a distance from one another that after disconnecting any circuit (for example, a bus section), its safe service is ensured in the presence of voltage in adjacent circuits. In particular, the distance between unprotected live parts located on both sides of the service corridor must correspond to the size G according to table 4.2.7 (see Fig. 4.2.16).

4.2.90. The width of the service corridor must ensure convenient maintenance of the installation and movement of equipment, and it must be at least (counting the clearance between the fences): 1 m - with one-sided arrangement of the equipment; 1.2 m - with double-sided equipment arrangement.

In the service corridor, where the drives of switches or disconnectors are located, the above dimensions must be increased to 1.5 and 2 m, respectively. With a corridor length of up to 7 m, the width of the corridor for two-way service may be reduced to 1.8 m.

Table 4.2.7

The shortest clear distances from live parts to various elements ZRU

(substations) 3-330 kV, protected by arresters, and indoor switchgear 110-330 kV, protected by surge suppressors 1 , (in the denominator) (Fig. 4.2.14-4.2.17)

Figure number	Name of distance	Designation	Insulation distance, mm, for rated voltage, kV
Figure number	Name of distance	Designation
	From live parts to grounded structures and building parts
	Between conductors of different phases
	From live parts to continuous fences
	From live parts to mesh fencing
	Between unprotected live parts of different circuits
	From unprotected live parts to the floor
	From unfenced outputs from the indoor switchgear to the ground when they do not exit into the territory of the outdoor switchgear and in the absence of vehicle passage under the outputs
	From the contact and the disconnector blade in the open position to the busbar connected to the second contact
	From unfenced cable outlets from the closed switchgear to the ground when cables exit to a support or portal not on the territory of the outdoor switchgear and in the absence of vehicle passage under the outlets

1 Surge suppressors have protective level switching overvoltage phase-ground 1.8 U f.

4.2.91. The width of the service corridor for switchgear with withdrawable elements and package transformer substations should ensure ease of control, movement and reversal of equipment and its repair.

When installing switchgear and package transformer substations in separate rooms, the width of the service corridor should be determined based on the following requirements:

for single-row installation - the length of the largest switchgear trolley (with all protruding parts) plus at least 0.6 m;

with double-row installation - the length of the largest switchgear trolley (with all protruding parts) plus at least 0.8 m.

If there is a corridor at the rear of the switchgear and package transformer substations for their inspection, its width must be at least 0.8 m; Individual local narrowings of no more than 0.2 m are allowed.

When installing switchgear and package transformer substations openly in production premises, the width of the free passage must be determined by the location of the production equipment, ensure the possibility of transporting the largest switchgear elements to the switchgear substations, and in any case it must be at least 1 m.

The height of the room must be no less than the height of the switchgear, package transformer substations, counting from busbar entries, jumpers or protruding parts of cabinets, plus 0.8 m to the ceiling or 0.3 m to the beams.

A lower room height is allowed if this ensures the convenience and safety of replacement, repair and adjustment of switchgear equipment, package transformer substations, busbar inputs and jumpers.

4.2.92. The calculated loads on the floors of premises along the path of transportation of electrical equipment must be taken into account the weight of the heaviest equipment (for example, a transformer), and the openings must correspond to their dimensions.

4.2.93. For overhead inputs into closed switchgear switchgears, package transformer substations and closed substations that do not cross passages or places where traffic is possible, etc., the distance from the lowest point of the wire to the ground surface must be at least E(Table 4.2.7 and Fig. 4.2.17).

At shorter distances from the wire to the ground, in the corresponding area under the input, either fencing the area with a fence 1.6 m high or a horizontal fence under the input must be provided. In this case, the distance from the ground to the wire in the plane of the fence must be at least the size E.

For overhead leads crossing passages or places where traffic is possible, etc., the distances from the lowest point of the wire to the ground should be taken in accordance with 2.5.212 and 2.5.213.

For air leads from the closed switchgear to the territory of the outdoor switchgear, the indicated distances should be taken according to the table. 4.2.5 for size G(see Fig. 4.2.6).

The distances between adjacent linear terminals of two circuits must be no less than the values given in table. 4.2.3 for size D, if partitions are not provided between the terminals of adjacent circuits.

In case of unorganized drainage, canopies should be provided on the roof of the indoor switchgear building over the air inlets.

4.2.94. Exits from the reactor plant should be carried out based on the following requirements:

1) with a switchgear length of up to 7 m, one exit is allowed;

2) with a switchgear length of more than 7 to 60 m, two exits must be provided at its ends; it is allowed to locate exits from the switchgear at a distance of up to 7 m from its ends;

3) if the length of the switchgear is more than 60 m, in addition to the exits at its ends, additional exits must be provided so that the distance from any point of the service corridor to the exit is no more than 30 m.

Exits can be made outside, to staircase or to another industrial premises of category G or D, as well as to other compartments of the switchgear, separated from this one by a fire door of fire resistance class II. In multi-storey switchgears, a second and additional exits can also be provided to a balcony with an external fire escape.

Cell gates with a leaf width of more than 1.5 m must have a wicket if they are used for personnel exit.

4.2.95. It is recommended that the floors of the switchgear rooms be installed over the entire area of each floor at the same level. The design of the floors must exclude the possibility of the formation of cement dust. The installation of thresholds in doors between separate rooms and in corridors is not allowed (for exceptions, see 4.2.100 and 4.2.103).

4.2.96. Doors from the switchgear must open towards other rooms or outwards and have self-locking locks that can be opened without a key from the switchgear side

Doors between compartments of one switchgear or between adjacent rooms of two switchgears must have a device that locks the doors in the closed position and does not prevent the doors from opening in both directions.

Doors between rooms (compartments) of switchgears of different voltages must open towards the switchgear with the lowest voltage.

Locks in the doors of switchgear rooms of the same voltage must be opened with the same key; keys to entrance doors Switchgears and other premises should not approach the locks of the chambers, as well as the door locks in the fences of electrical equipment.

The requirement to use self-locking locks does not apply to urban and rural distribution switchgears electrical networks voltage 10 kV and below.

4.2.97. Enclosing structures and partitions of switchgear and package transformer substations for the power plant's own needs should be made of non-combustible materials.

It is allowed to install switchgear and package transformer substations for your own needs in process rooms of substations and power plants in accordance with the requirements of 4.2.121.

4.2.98. In one switchgear room with a voltage of 0.4 kV and above, it is allowed to install up to two oil transformers with a power of each up to 0.63 MVA, separated from each other and from the rest of the switchgear room by a partition made of non-combustible materials with a fire resistance limit of 45 minutes, a height of at least transformer height, including bushings high voltage.

4.2.99. Devices related to starting devices for electric motors, synchronous compensators, etc. (switches, starting reactors, transformers, etc.) may be installed in a common chamber without partitions between them.

4.2.100. Voltage transformers, regardless of the mass of oil in them, may be installed in fenced switchgear chambers. In this case, a threshold or ramp must be provided in the chamber, designed to hold the full volume of oil contained in the voltage transformer.

4.2.101. Switch cells should be separated from the service corridor by solid or mesh barriers, and from each other by solid partitions made of non-combustible materials. These switches must be separated from the drive by the same partitions or shields.

Under each oil switch with an oil mass of 60 kg or more in one pole, an oil receiver is required for the full volume of oil in one pole.

4.2.102. In closed, free-standing, attached and built-in substations, in the chambers of transformers and other oil-filled devices with an oil mass in one tank of up to 600 kg, when the chambers are located on the ground floor with doors facing outside, oil collecting devices are not installed.

When the mass of oil or non-flammable environmentally friendly dielectric in one tank is more than 600 kg, an oil receiver must be installed, designed to hold the full volume of oil, or to retain 20% of the oil with discharge to the oil sump.

4.2.103. When constructing chambers above the basement, on the second floor and above (see also 4.2.118), as well as when constructing an exit from the chambers into the corridor under transformers and other oil-filled devices, oil receivers must be constructed in one of the following ways:

1) when the mass of oil in one tank (pole) is up to 60 kg, a threshold or ramp is made to hold the full volume of oil;

2) with an oil mass of 60 to 600 kg, an oil receiver designed to hold the full volume of oil is installed under the transformer (apparatus), or at the exit from the chamber there is a threshold or ramp to hold the full volume of oil;

3) with an oil weight of more than 600 kg:

an oil receiver containing at least 20% of the total volume of oil of the transformer or apparatus, with oil drainage into the oil sump. Oil drain pipes from oil receivers under transformers must have a diameter of at least 10 cm. On the side of the oil receivers, oil drain pipes must be protected with nets. The bottom of the oil receiver should have a slope of 2% towards the pit;

oil receiver without oil drainage into the oil sump. In this case, the oil receiver must be covered with a grate with a 25 cm thick layer of clean, washed granite (or other non-porous rock) gravel or crushed stone with a fraction of 30 to 70 mm and must be designed for the full volume of oil; The oil level should be 5 cm below the grate. The top level of gravel in the oil receiver under the transformer should be 7.5 cm below the opening of the air supply ventilation duct. The area of the oil receiver must be larger than the base area of the transformer or apparatus.

4.2.104. Ventilation of transformer and reactor rooms must ensure the removal of heat generated by them in such quantities that when they are loaded, taking into account the overload capacity and the maximum design temperature environment, heating of transformers and reactors did not exceed the maximum permissible value for them.

Ventilation of transformer and reactor rooms must be carried out in such a way that the temperature difference between the air leaving the room and entering it does not exceed: 15 °C for transformers, 30 °C for reactors with currents up to 1000 A, 20 °C for reactors with currents more than 1000 A.

If it is impossible to ensure heat exchange by natural ventilation, it is necessary to provide forced ventilation, and its operation must be monitored using alarm devices.

4.2.105. Supply and exhaust ventilation with a fence at the floor level and at the level of the upper part of the room should be carried out in the room where the switchgear and cylinders with SF6 gas are located.

4.2.106. RU rooms containing equipment filled with oil, SF6 gas or compound must be equipped exhaust ventilation, switched on from the outside and not connected to other ventilation devices.

In places with low winter temperatures Supply and exhaust ventilation openings must be equipped with insulated valves that can be opened from the outside.

4.2.107. In rooms where on-duty personnel stay for 6 hours or more, the air temperature must be ensured not lower than +18 °C and not higher than +28 °C.

In the repair area of the closed switchgear for the duration of the repair work a temperature of at least +5 °C must be ensured.

When heating rooms that contain SF6 equipment, heating devices with a heating surface temperature exceeding 250 °C (for example, heaters such as heating elements) should not be used.

4.2.108. Holes in the enclosing structures of buildings and premises after laying current conductors and other communications should be sealed with a material that provides fire resistance not lower than the fire resistance of the enclosing structure itself, but not less than 45 minutes.

4.2.109. To prevent the entry of animals and birds, other openings in external walls must be protected with nets or gratings with cells measuring 10 x 10 mm.

4.2.110. Overlapping cable ducts and double floors must be made of removable slabs made of fireproof materials flush with the clean floor of the room. The weight of an individual floor slab should be no more than 50 kg.

4.2.111. Laying transit cables and wires in the chambers of devices and transformers, as a rule, is not allowed. In exceptional cases, their installation in pipes is allowed.

Electrical wiring of lighting and control and measurement circuits located inside chambers or located near non-insulated live parts can be allowed only to the extent necessary for connections (for example, to instrument transformers).

4.2.112. Laying related (non-transit) heating pipelines into the switchgear premises is permitted provided that solid welded pipes are used without valves, etc., and welded ventilation ducts are used without valves and other similar devices. Transit laying of heating pipelines is also permitted, provided that each pipeline is enclosed in a continuous waterproof shell.

4.2.113. When choosing a switchgear circuit containing SF6 devices, simpler circuits should be used than in air-insulated switchgear.

Page 1 of 12

REQUIREMENTS FOR DISTRIBUTION DEVICES AND TASKS OF THEIR MAINTENANCE

Switchgear units (RU) of substations are complexes of structures and equipment designed for receiving and distributing electrical energy.
Switchgears can be open (OSU) or closed (ZRU). Complete switchgears (Switchgear) for installation indoors and directly on outdoors(KRUN). They are manufactured in stationary and roll-out versions, and are supplied assembled or fully prepared for assembly. Sealed switchgears that use SF6 gas as an insulating and arc-extinguishing medium are called switchgear.

TO The following requirements apply to switchgear equipment::

According to its nominal data, the switchgear equipment must satisfy operating conditions both in normal mode and during short circuit. Under normal operating conditions, heating of conductors by current should not exceed the values established by the standards. This provides reliable operation current-carrying parts and guarantees an economically justified service life of the insulation, excluding its accelerated thermal aging. In short circuit mode, the switchgear equipment must have the necessary thermal and electrodynamic resistance.
The insulation of the equipment must correspond to the rated voltage of the network and withstand possible voltage increases during switching and atmospheric overvoltages. One of the main conditions for reliable operation of insulating structures is keeping the insulation clean - systematic cleaning, washing, coatings with hydrophobic pastes; for closed switchgear - protection against penetration of dust and harmful gases into the premises; in KRUN - sealing cabinets, coating insulation with hydrophobic pastes.
The equipment must operate reliably under permissible overloads, which should not lead to damage and a reduction in its service life.
The production premises of the reactor plant must be convenient and safe when servicing equipment by personnel. Switchgear switchgears with voltages of 400 kV and higher must be equipped with biological protection means in the form of stationary, portable or inventory screens, means personal protection- shielding suits. Heating of structures located near live parts accessible to personnel should not exceed 50°C.
Temperature and air humidity in the indoor switchgear must be maintained such that dew does not occur on the insulators; temperature in summer time should not exceed 40°C. Ventilation openings must have louvers or metal mesh. Windows in the closed switchgear must be locked or protected with nets, and openings and openings in walls or cells must be sealed to prevent the possibility of animals entering. birds. The roof must be in good condition. Floor coverings must not allow the formation of cement dust.
The switchgear must be equipped with working and emergency electric lighting. Lighting equipment must be installed in such a way as to ensure safe operation.
For personnel orientation, all equipment and especially switching device drives must be provided with clear, conspicuous inscriptions indicating the name of the equipment and the dispatcher name of the electrical circuit to which the inscription refers. In the switchgear, an atypical arrangement of the drive handles of bus disconnectors is unacceptable, when, for example, some disconnectors are turned off by moving the drive handle down, others - up. Switches and their drives, disconnectors, separators, short-circuiters and stationary grounding switches must have “On” and “Off” position indicators. Switchgears must be equipped with an interlock that prevents the possibility of erroneous operations with disconnectors, grounding blades, and short circuiters. Locking devices, except mechanical ones, must be permanently sealed.
The RU premises must contain safety equipment and fire extinguishing equipment.

The tasks of maintaining the reactor plant are:

ensuring compliance of operating modes of the reactor plant and individual electrical circuits technical specifications installed equipment;
maintaining at each period of time such a scheme of switchgear and substations so that they best meet the requirements of reliable operation of the power system and trouble-free selective operation of relay protection and automation devices;
systematic supervision and care of the equipment and premises of the reactor plant, elimination as soon as possible of identified malfunctions and defects, since their development may lead to operational failures and accidents;
control over the timely implementation of preventive tests and equipment repairs;
compliance with the established order and sequence of switching operations in the switchgear.

Inspection of the reactor plant without shutting down the equipment should be carried out:

at facilities with constant personnel duty - at least once every 3 days, in addition, in the dark to detect the presence of discharges, corona - at least once a month;
at facilities without permanent duty - at least once a month, and at transformer and distribution points - at least once every 6 months.
after switching off the short circuit.

In case of unfavorable weather (heavy fog, sleet, ice) or increased contamination of the outdoor switchgear, additional inspections are required. During inspection, it is strictly prohibited to perform any work on the equipment.
During inspections of the reactor plant, all comments are recorded in a log of defects and malfunctions and brought to the attention of the managers of the energy enterprise, who take appropriate measures to eliminate the identified violations as soon as possible.
RUs with voltages above 1000 V are operated in accordance with the "Rules technical operation electrical stations and networks."
Tests of the electrical equipment of the reactor plant should usually be carried out during periods of its repair.
Current repairs electrical equipment of the reactor plant, as well as checking its operation (testing) must be carried out in accordance with the schedule approved by the chief engineer of the power enterprise, with the exception of unforeseen emergency and other urgent work that is carried out outside the schedule with its own procedure for registering these works.

4.1.24. Switchgears installed in rooms accessible to uninstructed personnel must have live parts covered with solid fences.

If a switchgear is used with open live parts, it must be fenced. In this case, the fence must be mesh, solid or mixed, with a height of at least 1.7 m. The distance from the mesh fence to the non-insulated live parts of the device must be at least 0.7 m, and from solid ones - in accordance with 4.1.14. The width of passages is taken in accordance with the requirements given in 4.1.21.

4.1.25. The termination of wires and cables must be made so that it is located inside the device.

4.1.26. Removable barriers must be strengthened so that their removal is impossible without the use of tools. The doors must be locked with a key.

4.1.27. The installation of complete switchgears and substations (switchgear switchgear, package transformer substations) must comply with the requirements given in Chapter. 4.2 for switchgear and package substations above 1 kV.

Installation of switchgear outdoors

4.1.28. When installing switchgear outdoors, the following requirements must be observed:

1. The device must be located on a planned site at a height of at least 0.2 m from the planning level and must be designed in accordance with environmental conditions. In areas where snow drifts of 1 m or more in height are observed, cabinets should be installed on elevated foundations.

2. The cabinets must be provided with local heating to ensure normal operation of devices, relays, measuring instruments and metering devices in accordance with GOST requirements.

Chapter 4.2

Switchgears and substations

Voltage above 1 kV

Scope, definitions

4.2.1. This chapter of the Rules applies to stationary switchgear and alternating current substations with voltages above 1 kV. The rules do not apply to special switchgear and substations regulated by special technical specifications, and for mobile electrical installations.

4.2.2. A switchgear is an electrical installation that serves to receive and distribute electricity and contains switching devices, busbars and connecting busbars, auxiliary devices (compressor, battery, etc.), as well as protection devices, automation and measuring instruments.

An open switchgear (OSD) is a switchgear, all or the main equipment of which is located in the open air.

A closed switchgear is called a switchgear, the equipment of which is located in the building.

4.2.3. A complete switchgear is a switchgear consisting entirely or partially closed cabinets or units with built-in devices, protection and automation devices, supplied assembled or fully prepared for assembly.

Complete switchgear designed for indoor installation, abbreviated as KRU. Complete switchgear designed for outdoor installation, abbreviated as KRUN.

4.2.4. A substation is an electrical installation used for the conversion and distribution of electricity and consisting of transformers or other energy converters, switchgear, control devices and auxiliary structures.

Depending on the predominance of one or another function of substations, they are called transformer or converter.

4.2.5. An attached substation (attached RU) is a substation (RU) directly adjacent (adjacent) to the main building.

4.2.6. A built-in substation (built-in switchgear) is a closed substation (closed switchgear), inscribed (inscribed) in the contour of the main building.

4.2.7. An in-shop substation is a substation located inside industrial building(open or in a separate indoors).

4.2.8. A complete transformer (converter) substation is a substation consisting of transformers (converters) and units (switchgear or switchgear and other elements) supplied assembled or fully prepared for assembly. Complete transformer (converter) substations (KTP, KPP) or parts of them installed indoors are classified as indoor installations; those installed outdoors are classified as outdoor installations.

4.2.9. A pole (mast) transformer substation is an open transformer substation, all of the equipment of which is installed on structures or on overhead line supports at a height that does not require substation fencing.

4.2.10. A distribution point (DP) is a switchgear intended for receiving and distributing electricity at one voltage without conversion and transformation, which is not part of the substation.

4.2.11. A chamber is a room intended for the installation of devices and tires.

A closed cell is a cell that is closed on all sides and has solid (not mesh) doors.

A fenced chamber is a chamber that has openings protected in whole or in part by non-solid (mesh or mixed) fences.

Mixed fencing refers to fencing made from mesh and solid sheets.

The explosion chamber is called closed chamber, designed to localize possible emergency consequences in case of damage to the devices installed in it and having access to the outside or into the explosion corridor.

4.2.12. A service corridor is a corridor along the switchgear chambers or cabinets, intended for servicing devices and buses.

An explosive corridor is a corridor into which the doors of the explosive chambers open.

Rules for electrical installations in questions and answers. Section 4. Switchgears and substations. A manual for studying and preparing for pro Krasnik Valentin Viktorovich

Enclosed switchgears and substations

Question 72. What devices should be provided in the premises of 35-220 kV closed switchgear and in closed transformer chambers?

Answer. It is necessary to provide stationary devices or the possibility of using mobile or inventory lifting devices to mechanize repair work and equipment maintenance.

In rooms with switchgear, a platform should be provided for repair and adjustment of withdrawable elements. The repair site must be equipped with means for testing switch drives and control systems (clause 4.2.82).

Question 73. In what rooms should closed switchgear switchgears of different voltage classes be placed?

Answer. Should be placed, as a rule, in separate rooms. This requirement does not apply to transformer substations of 35 kV and below, as well as switchgear.

Question 74. In what places are transformer rooms and switchgear switchgear not allowed?

Answer. It is not allowed to post:

1) under production premises with a wet technological process, under showers, bathtubs, etc.;

2) directly above and below the premises in which, within the area occupied by the switchgear or transformer rooms, more than 50 people can simultaneously be present for a period of more than 1 hour. This requirement does not apply to transformer rooms with dry transformers or with non-flammable filling, as well as switchgear for industrial enterprises (clause 4.2.85).

Question 75. What should be the clear distances between bare live parts of different phases, from bare live parts to grounded structures and fences, floor and ground, as well as between bare live parts of different circuits?

Answer. Must be no less than the values given in the table. 4.2.7 (clause 4.2.86).

Question 76. What are the requirements of the Rules for bare live parts in relation to electrical safety?

Answer. They must be protected from accidental touches (placed in cells, fenced with nets, etc.).

When non-insulated live parts are located outside the chambers, they must be fenced. The height of the passage under the fence must be at least 1.9 m (clause 4.2.88).

Question 77. Are barriers allowed in enclosed cells?

Answer. Their use in these chambers is not allowed (clause 4.2.88).

Question 78. What safety measures during servicing should the width of the servicing corridor ensure?

Answer. It must ensure convenient maintenance of the installation and movement of the equipment, and it must be no less (counting the clearance between the fences): 1 m – with one-sided arrangement of the equipment; 1.2 m – with double-sided equipment arrangement.

Table 4.2.7

The shortest clear distances from live parts to various elements of 3-330 kV indoor switchgear (substations), protected by arresters, and 110–330 kV indoor switchgear, protected by surge suppressors (in the denominator)

Question 79. Based on what requirements is it necessary to determine the width of the service corridor when installing switchgear and package transformer substations in separate rooms?

Answer. It is necessary to determine based on the following requirements:

for single-row installation - the length of the largest of the switchgear trolleys (with all protruding parts) plus at least 0.6 m;

for a double-row installation - the length of the largest of the switchgear trolleys (with all protruding parts) plus at least 0.8 m.

Question 80. How should the width of the free passage be determined during open installation of switchgear and package transformer substations in industrial premises?

Answer. It must be determined by the location of the production equipment, ensure the possibility of transporting the largest elements of switchgear and package transformer substations, and in any case it must be at least 1 m (clause 4.2.91).

Question 81. What should be the height of the room?

Answer. There must be no less than the height of the switchgear, package transformer substations, counting from busbar entries, jumpers or protruding parts of cabinets, plus 0.8 m to the ceiling or 0.3 m to the beams (clause 4.2.91).

Question 82. Based on what requirements should exits from the reactor plant be carried out?

Answer. Must be fulfilled based on the following requirements:

1) with a switchgear length of up to 7 m, one exit is allowed;

2) with a switchgear length of more than 7 m to 60 m, two exits must be provided at its ends; it is allowed to locate exits from the switchgear at a distance of up to 7 m from its ends;

3) if the length of the switchgear is more than 60 m, in addition to the exits at its ends, additional exits must be provided so that the distance from any point in the service corridor to the exit is no more than 30 m (clause 4.2.94).

Question 83. Where can the exits from the switchgear be made?

Answer. Can be made outside, onto a staircase or into another production room of category G or D, as well as into other compartments of the switchgear, separated from this fire door II degree of fire resistance. In multi-storey switchgears, a second and additional exits can also be provided to a balcony with an external fire escape.

Cell gates with a leaf width of more than 1.5 m must have a wicket if they are used for personnel exit (clause 4.2.94).

Answer. It is recommended to carry out the entire area of each floor at one level. The design of the floors must exclude the possibility of the formation of cement dust. The installation of thresholds in doors between separate rooms and in corridors is not allowed (exceptions - in answers to questions 88 and 90) (clause 4.2.95).

Question 85. What are the requirements of the Rules for switchgear doors?

Answer. Doors from the switchgear must open towards other rooms or outwards and have self-locking locks that can be opened without a key from the switchgear side.

Doors between rooms (compartments) of switchgears of different voltages must open towards the switchgear with the lowest voltage.

Locks in the doors of switchgear rooms of the same voltage must be opened with the same key; keys to the entrance doors of the switchgear and other premises should not fit the locks of the cells, as well as the locks of doors in the fences of electrical equipment.

The requirements for the use of self-locking locks do not apply to switchgear of urban and rural distribution electrical networks with a voltage of 10 kV and below (clause 4.2.96).

Question 86. What is the permissible number of oil transformers that can be installed in one room of a switchgear with a voltage of 0.4 kV and higher?

Answer. It is allowed to install up to two oil transformers with a power of each up to 0.63 MV-A, separated from each other and from the rest of the switchgear room by a partition made of non-combustible materials with a fire resistance limit of 45 minutes, a height not less than the height of the transformer, including high voltage bushings (clause 4.2 .98).

Question 87. Is it allowed to install devices related to starting devices for electric motors, synchronous compensators, etc. (switches, starting reactors, transformers, etc.) in a common chamber without partitions between them?

Answer. Such installation of launchers is allowed (clause 4.2.99).

Question 88. In which switchgear chambers is it permissible to install voltage transformers regardless of the mass of oil in them?

Answer. It is allowed to install in fenced RU chambers. In this case, a threshold or ramp must be provided in the chamber, designed to hold the full volume of oil contained in the voltage transformer (clause 4.2.100).

Question 89. Should oil collection devices be installed in closed free-standing, attached and built-in industrial premises PS, in the chambers of transformers and other oil-filled devices with an oil mass in one tank of up to 600 kg when the chambers are located on the ground floor with doors facing outside?

Answer. Under such conditions, oil collection devices are not installed (clause 4.2.102).

Question 90. What methods should be used to construct oil receivers when constructing chambers above the basement, on the second floor and above, as well as when constructing exits from the chambers into the corridor under transformers and other oil-filled devices?

Answer. Oil receivers must be made in one of the following ways:

1) when the mass of oil in one tank (pole) is up to 60 kg, a threshold or ramp is made to hold the full volume of oil;

3) with an oil weight of more than 600 kg:

an oil receiver containing at least 20% of the total volume of oil of the transformer or apparatus, with oil drainage into the oil sump.

The oil drain pipes from the oil receivers under the transformers must have a diameter of at least 10 cm. On the side of the oil receivers, the oil drain pipes must be protected with nets. The bottom of the oil receiver should have a slope of 2% towards the pit;

oil receiver without oil drainage into the oil sump. In this case, the oil receiver must be covered with a grate with a 25 cm thick layer of clean, washed granite (or other non-porous rock) gravel or crushed stone with a fraction of 30 to 70 mm and must be designed for the full volume of oil; The oil level should be 5 cm below the grate. The upper level of gravel in the television receiver under the transformer should be 7.5 cm below the air supply hole ventilation duct. The area of the oil receiver must be greater than the area of the base of the transformer or apparatus (clause 4.2.103).

Question 91. How should the ventilation of transformer rooms be carried out?

Answer. It must be done in such a way that the temperature difference between the air leaving the room and entering it does not exceed:

15 °C – for transformers;

30 °C – for reactors with currents up to 1000 A;

20 °C – for reactors with currents of more than 1000 A (clause 4.2.104).

Question 92. What kind of ventilation should be installed in switchgear rooms containing equipment filled with oil, SF6 or compound?

Answer. Must be equipped with exhaust ventilation, switched on from the outside and not connected to other ventilation devices.

In places with low winter temperatures, supply and exhaust ventilation holes must be equipped with insulated valves that can be opened from the outside (clause 4.2.106).

Question 93. What air temperature should be ensured in rooms where on-duty personnel remain for 6 hours or more?

Answer. The air temperature must be ensured not lower than +18 °C and not higher than +28 °C.

In the repair area of the closed switchgear, a temperature of at least +5 °C must be ensured during repair work (clause 4.2.107).

Question 94. What heating devices should not be used when heating rooms that contain SF6 equipment?

Answer. Heating devices with a heating surface temperature exceeding 250 °C (for example, heating element type heaters) should not be used (clause 4.2.107).

Question 95. What material should cable ducts and double floors be made of?

Answer. Must be made of removable slabs made of fireproof materials flush with the clean floor of the room. The mass of an individual floor slab should be no more than 50 kg (clause 4.2.110).

Question 96. Is it allowed to lay transit cables and wires in the chambers of devices and transformers?

Answer. Such laying is, as a rule, not allowed. In exceptional cases, their installation in pipes is allowed (clause 4.2.111).

Question 97. Under what conditions is it permissible to lay related (non-transit) heating pipelines into the switchgear premises?

Answer. Allowed provided that solid welded pipes are used without valves, etc., and welded ventilation ducts are used without valves and other similar devices. Transit laying of heating pipelines is also allowed, provided that each pipeline is enclosed in a continuous waterproof shell (clause 4.2.112).

This text is an introductory fragment. From the book Rules for Electrical Installations in Questions and Answers [A manual for studying and preparing for a knowledge test] author

Complete switchgears for indoor and outdoor installation Question. What is included in the scope of testing switchgear and switchgear switchgear? Answer. The scope of testing includes: measurement of insulation resistance: primary circuits, secondary circuits; high voltage testing of industrial

From the book Rules for Electrical Installations in Questions and Answers. Chapter 1.8. Acceptance testing standards. A guide for studying and preparing for knowledge testing author Krasnik Valentin Viktorovich

Section 4. SWITCH DEVICES AND SUBSTATIONS

From the book Rules for Electrical Installations in Questions and Answers. Section 4. Switchgears and substations. A guide for studying and preparing for pro author Krasnik Valentin Viktorovich

Chapter 4.1. SWITCH DEVICES WITH VOLTAGE up to 1 kV AC and up to 1.5 kV DC Application area Question. Which RUs are covered by this chapter of the Rules? Answer. Applies to switchgear and NKU voltages up to 1 kV AC and up to 1.5 kV

From the book Handbook on the construction and reconstruction of power transmission lines with voltage 0.4–750 kV author Uzelkov Boris

Chapter 4.2. SWITCH DEVICES AND SUBSTATIONS WITH VOLTAGES ABOVE 1 kV Scope, definitions Question. Which switchgear and transformer substations (TS) are covered by this chapter of the Rules? Answer. Applies to stationary switchgear and substation alternating current

From the author's book

Open distribution devices Question. How should connections of flexible wires be made in spans, in loops at supports, connections in spans and to hardware terminals? Answer. Must be performed by crimping using connecting clamps, and connections in loops

From the author's book

Intrashop switchgears and transformer substations Question. Where can in-shop switchgear and substations be located? Answer. Switchgear and substations with oil-filled equipment can be located on the first and second floors in the main and auxiliary rooms

From the author's book

Input devices, distribution boards, distribution points, group panels Question. What should be installed at the entrance to the building? Answer. A VU or ASU must be installed. One or more VU or ASU (7.1.22) may be installed in a building. Question. What

From the author's book

Switchgears, transformer and converter substations Question. Is it allowed to build directly in explosive zones switchgear with voltages up to 1 kV and higher, transformer substations and converter substations with electrical equipment? general purpose(without funds

From the author's book

Switchgears, transformer and distribution substations Question. Is it allowed to install switchgear with voltages up to 1 kV and higher in fire hazardous areas? Answer. Their installation in fire hazardous areas of any class is not recommended. If necessary, install the switchgear

From the author's book

1.8.25. Complete switchgear for indoor and outdoor installation (KRU and KRUN) Question 113. What is the scope and standards for measuring the insulation resistance of KRU and KRUN? Answer. The insulation resistance is measured: primary circuits. The measurement is carried out with a megohmmeter on

From the author's book

Chapter 4.1. SWITCH DEVICES WITH VOLTAGE UP TO 1 KV AC AND UP TO 1.5 KV DC Scope Question 1. Which switchgears are covered by this chapter of the Rules? Answer. Applies to distribution devices

From the author's book

Chapter 4.2. SWITCHGEARS AND SUBSTATIONS WITH VOLTAGES ABOVE 1 KV Scope, definitions Question 20. Which switchgears and transformer substations (TS) are covered by this chapter of the Rules? Answer. Spreads on

From the author's book

Open distribution devices Question 53. How should flexible wire connections be made in spans, in loops at supports, connections in the span and to hardware terminals? Answer. Must be performed by crimping using connecting clamps, and connections in loops

From the author's book

In-shop switchgears and transformer substations Question 98. Where can in-shop switchgear and substations with oil-filled equipment be located? Answer. Can be located on the first and second floors in the main and auxiliary production premises,

From the author's book

Section 2 Complete transformer substations and distribution devices 2.1. COMPLETE TRANSFORMER SUBSTATIONS Complete transformer block substations (KTPB) (Fig. 2.1) are designed for receiving, converting and distributing electrical power

From the author's book

2.2. COMPLETE DISTRIBUTION DEVICES A complete distribution device (KRU), consisting of prefabricated one-way service chambers "SamaraElectron-Shield" of the KSO-SESCH series (hereinafter referred to as KSO), is intended for the reception and distribution of electrical energy

Section 4. Switchgears and substations

Chapter 4.2. Switchgears and substations with voltage above 1 kV

4.2.1. This chapter of the Rules applies to stationary switchgear and alternating current substations with voltages above 1 kV. The rules do not apply to special switchgear and substations regulated by special technical conditions, and to mobile electrical installations.

An open switchgear (OSD) is a switchgear, all or the main equipment of which is located in the open air.

A closed switchgear is called a switchgear, the equipment of which is located in the building.

4.2.3. A complete switchgear is a switchgear consisting of fully or partially closed cabinets or blocks with built-in devices, protection and automation devices, supplied assembled or fully prepared for assembly.

A complete switchgear intended for indoor installation is abbreviated as KRU. A complete switchgear intended for outdoor installation is abbreviated as KRUN.

Depending on the predominance of one or another function of substations, they are called transformer or converter.

4.2.5. An attached substation (attached RU) is a substation (RU) directly adjacent (adjacent) to the main building.

4.2.6. A built-in substation (built-in switchgear) is a closed substation (closed switchgear), inscribed (inscribed) in the contour of the main building.

4.2.7. An intra-shop substation is a substation located inside a production building (open or in a separate enclosed room).

4.2.10. A distribution point (DP) is a switchgear intended for receiving and distributing electricity at one voltage without conversion and transformation, which is not part of the substation.

4.2.11. A chamber is a room intended for the installation of devices and tires.

A closed cell is a cell that is closed on all sides and has solid (not mesh) doors.

A fenced chamber is a chamber that has openings protected in whole or in part by non-solid (mesh or mixed) fences.

Mixed fencing refers to fencing made from mesh and solid sheets.

An explosion chamber is a closed chamber designed to localize possible emergency consequences in the event of damage to the devices installed in it and having access to the outside or into the blast corridor.

4.2.12. A service corridor is a corridor along the switchgear chambers or cabinets, intended for servicing devices and buses.

An explosive corridor is a corridor into which the doors of the explosive chambers open.

General requirements

4.2.13. Electrical equipment, live parts, insulators, fastenings, fences, bearing structures, insulation and other distances must be selected and installed in such a way that:

1) forces, heating, electric arc or other phenomena accompanying its operation (sparking, release of gases, etc.) caused by normal operating conditions of the electrical installation could not lead to damage to the equipment and the occurrence of a short circuit or ground fault, or cause harm service personnel;

2) in case of violation of the normal operating conditions of the electrical installation, the necessary localization of damage caused by the action of the short circuit was ensured;

3) when the voltage is removed from any circuit, the devices, current-carrying parts and structures related to it could be safely inspected, replaced and repaired without disrupting the normal operation of adjacent circuits;

4) the possibility of convenient transportation of equipment was ensured.

The requirements of clause 3 do not apply to switchgear type assemblies above 1 kV in substations, the repair of which is carried out when the entire switchgear is disconnected.

4.2.14. When using open blade disconnectors or open blade separators to switch off and on the current of unloaded transformers, charging or equalizing current of power lines, ground fault current, the distances between live parts and from live parts to the ground must comply with the requirements of this chapter and special directive documents approved in in the prescribed manner.

4.2.15. The selection of devices, conductors and insulators for short circuit conditions must be made in accordance with Chapter. 1.4.

4.2.16. The structures on which the electrical equipment specified in 4.2.15 is installed and secured must withstand loads and impacts from the weight of the equipment, wind, ice, as well as those arising from a short circuit.

Building construction, located near live parts and accessible to the touch of personnel, should not heat up from exposure electric current up to a temperature of 50 °C and above; inaccessible to touch - up to 70 °C and above.

Structures may not be tested for heating if the current-carrying parts located near them pass alternating current 1000A or less.

4.2.17. In all switchgear circuits, provision must be made for the installation of disconnecting devices with a visible break, providing the ability to disconnect all devices (switches, separators, fuses, current transformers, voltage transformers, etc.) of each circuit from the busbars, as well as from other voltage sources.

This requirement does not apply to switchgear and switchgear switchgear cabinets with withdrawable trolleys, high-frequency suppressors and coupling capacitors, voltage transformers installed on outgoing lines, arresters installed at transformer terminals and on outgoing lines, as well as power transformers with cable inputs.

In some cases, due to design or circuit considerations, it is allowed to install current transformers before the disconnector that disconnects the remaining circuit devices from voltage sources.

4.2.18. The switch or its drive must have a clearly visible and reliably operating position indicator ("on", "off"). The use of signal lamps as the only indicators of the switch position is not permitted. If the switch does not have open contacts and its drive is separated from the switch by a wall, then the indicator must be on both the switch and the drive.

4.2.19. When the switchgear and substations are located in places where the air may contain substances that impair the performance of insulation or have a destructive effect on equipment and buses, measures must be taken to ensure reliable operation of the installation: reinforced insulation is used; Tires made of material resistant to environmental influences are used, or they are painted protective coating; Switchgear and substations are located on the side of the prevailing wind direction; Switchgear and substations are made according to the simplest schemes; closed design of switchgear and substations, protected from the penetration of dust, harmful gases or vapors into the room.

When constructing outdoor switchgear near sea coasts, salt lakes, chemical plants, as well as in places where long-term operating experience has established the destruction of aluminum from corrosion, special aluminum and steel-aluminum wires protected from corrosion should be used.

4.2.20. When the switchgear and substations are located at an altitude of more than 1000 m above sea level, air insulation gaps, suspended insulation and external insulation of electrical equipment must be selected in accordance with the requirements given in 4.2.53, 4.2.54, 4.2.82, 4.2.83, taking into account amendments to compensate for the decrease in electrical insulation strength at reduced atmospheric pressure.

4.2.21. In outdoor switchgear, switchgear and unheated indoor switchgear, where the ambient temperature can be below minus 25 °C, oil heating must be provided oil switches.

In addition, regardless of the minimum temperature, heating must be provided for the drive mechanisms of oil and air circuit breakers, valve blocks of air circuit breakers, their unit cabinets, as well as other cabinets in which equipment or clamps for internal installation are used.

Heating of relays and measuring instruments must be carried out in accordance with the requirements given in GOST, heating of meters - in accordance with 1.5.27 and 1.5.28.

4.2.22. The busbars of switchgears and substations should, as a rule, be made of aluminum, steel-aluminum and steel wires, strips, pipes and busbars made of aluminum and aluminum alloys electrical purposes.

Conductors should be made in accordance with the requirements of Chapter. 2.2.

4.2.23. The designation of phases of electrical equipment and busbars of switchgears and substations must be carried out in accordance with the requirements of Chapter. 1.1.

4.2.24. Switchgears of 3 kV and above must be equipped with operational interlocking, eliminating the possibility of:

turning on switches, separators and disconnectors to grounding blades and short circuits;

connecting grounding blades to a busbar that is not separated by disconnectors from the energized busbar;

turning off and on by separators and load current disconnectors, if this is not provided for by the design of the device.

On the grounding blades of linear disconnectors on the line side, it is allowed to install only a mechanical interlock with a disconnector drive and a device for locking the grounding blades with locks in the off position.

For RU with simple circuits electrical connections It is recommended to use mechanical (key) operational interlocking, and in all other cases - electromagnetic. Drives of disconnectors accessible to unauthorized persons must have devices for locking them with locks in the off and on positions.

4.2.25. Switchgear and substations above 1 kV must be equipped with stationary grounding blades that ensure, in accordance with safety requirements, the grounding of devices and busbars, as a rule, without the use of portable grounding.

Grounding blades must be painted black. The handles of the grounding knife drives should be painted red, and the handles of other drives should be painted in the colors of the equipment.

In places where stationary grounding blades cannot be used, contact surfaces must be prepared on the current-carrying and grounding busbars for connecting portable grounding conductors.

If there are voltage transformers, the grounding of the busbars should be carried out, as a rule, by the grounding blades of the voltage transformer disconnectors.

4.2.26. Mesh and mixed fencing of live parts and electrical equipment must have a height above the planning level for outdoor switchgear and openly installed transformers of 2 or 1.6 m (taking into account the requirements of 4.2.57 and 4.2.58), and above the floor level for indoor switchgear and transformers installed inside buildings, 1.9 m; the nets must have holes measuring at least 10x10 mm and no more than 25x25 mm, as well as devices for locking them. The lower edge of these fences in the outdoor switchgear should be located at a height of 0.1-0.2 m, and in the indoor switchgear - at floor level.

External fences must be made in accordance with the requirements given in 4.2.39.

The use of barriers is allowed at the entrance to chambers of switches, transformers and other devices for inspection of chambers in the presence of voltage on live parts. Barriers must be installed at a height of 1.2 m and be removable. If the height of the floor of the cells above ground level is more than 0.3 m, it is necessary to leave a distance of at least 0.5 m between the door and the barrier or provide an area in front of the door for inspection.

4.2.27. In cases where deformations of wires (busbars) caused by temperature changes, vibration, etc. can cause dangerous mechanical stresses in wires or insulators, measures should be taken to prevent the occurrence of such stresses (compensators, weakened tension, etc.) .

4.2.28. Indicators of the oil level and temperature of oil-filled transformers and devices and other indicators characterizing the condition of the equipment must be located in such a way as to provide convenient and safe conditions to access and observe them without relieving tension (for example, from the side of the passage into the chamber).

To take oil samples, the distance from the floor or ground level to the transformer tap or apparatus must be at least 0.2 m or an appropriate pit must be provided.

4.2.29. Electrical wiring of protection, measurement, alarm and lighting circuits laid according to electrical devices with oil filling, must be made with wires with oil-resistant insulation.

4.2.30. To reduce heating by direct rays of the sun, transformers, reactors and capacitors for outdoor installation should be painted in bright hues paints resistant to atmospheric influences and exposure to oil.

4.2.31. Switchgears and substations must be equipped with electric lighting. Lighting fixtures must be installed in such a way that they can be safely maintained.

4.2.32. The switchgear and substations must be provided with telephone communications in accordance with the adopted service system.

4.2.33. The placement of switchgear and substations, the master plan and engineering preparation of the territory and their protection from flooding, landslides, avalanches, etc. must be carried out in accordance with the requirements of SNiP Gosstroy of Russia.

4.2.34. The layout and design of outdoor switchgear and closed switchgear must provide for the possibility of using mechanisms, including special ones, for installation and repair work.

4.2.35. The distances between switchgears (substations) and trees more than 4 m high must be such that damage to equipment and busbars is prevented when a tree falls.

4.2.36. For switchgear and substations located in residential and industrial areas, measures must be taken to reduce the noise generated by operating electrical equipment (transformers, synchronous compensators, etc.) to the values specified in SNiP II-12-77 of the Gosstroy of Russia.

4.2.37. Switchgears and substations with permanent personnel on duty, with operational and repair personnel constantly located on them, as well as if there are residential buildings near them, must be provided with drinking water by installing a drinking water supply system, artesian wells or wells.

4.2.38. For switchgears and substations with permanent personnel on duty and having water supply, insulated restrooms with sewerage must be installed. If there are no sewer lines near the substations, local sewerage devices(settlers, filters). For substations without constant personnel duty, it is allowed to install non-insulated latrines with waterproof cesspools.

When substations of 110 kV and above are located without constant personnel duty nearby existing systems water supply and sewerage (at a distance of up to 0.5 km), sanitary sewerage units must be provided in the building of the general substation control point (SCU).

4.2.39. The territory of the outdoor switchgear and substations must be fenced with an external fence 1.8-2.0 m high. External fences more than 2.0 m high can be used in places with high snow drifts, as well as for substations with a special regime of access to their territory.

Auxiliary structures (workshops, warehouses, control centers, etc.) located on the territory of the outdoor switchgear should be fenced with an internal fence 1.6 m high.

When outdoor switchgear (substations) are located on the territory of power plants, these outdoor switchgear (substations) must be fenced with an internal fence 1.6 m high.

Fences can be solid, mesh or lattice.

Fences may not be provided:

for closed substations located in a protected area industrial enterprise;

for closed substations located in cities and towns;

for pole substations (see also 4.2.134).

4.2.40. Metal structures of indoor switchgears, outdoor switchgears and substations, as well as underground parts of metal and reinforced concrete structures must be protected from corrosion.

4.2.41. For the territory of outdoor switchgears and substations, where, under normal operating conditions, oil leaks may occur from oil equipment rooms, from oil warehouses, from machine rooms, as well as from transformers and switches during repair and other work, devices must be provided for its collection and removal from in order to prevent the possibility of oil getting into water bodies.

4.2.42. Alternating current should be used as operating current at substations in all cases where this is possible and leads to simplification and reduction in cost of electrical installations while ensuring the necessary reliability of their operation.

Installation of switchgear outdoors

Chapter 4.2

Switchgears and substations

Voltage above 1 kV

Scope, definitions

Read also