Particular attention during the construction of overhead lines should be paid to compliance with the dimensions of the intersection and convergence of overhead lines with each other, with structures, communication and signaling lines (LS), relay network lines (RS), roads, pipelines, etc.
Overhead power lines should be placed so that the supports do not block the entrances to buildings and entrances to courtyards and do not impede the movement of vehicles and pedestrians. In places where there is a danger of vehicles colliding with supports, they must be protected (for example, by bollards).
On overhead power lines with a voltage of up to 1 kV, the distance from the wires with the largest sag to the ground and the carriageway of the streets must be at least 6 m. In hard-to-reach areas, this distance can be reduced to 3.5 m, and in inaccessible areas (mountain slopes, rocks, cliffs, etc.) - up to 1 m. At the intersection of the impassable part of the street with branches from the overhead line to the inputs, the distance from the wires to the sidewalks and footpaths can be reduced to 3.5 m.
On overhead lines with a voltage of more than 1 kV during normal operation, the shortest distance, m, from wires to the ground, buildings and structures in a populated area should be:
In an uninhabited area, the distances from the wires of the overhead line to the surface of the earth during normal operation of the overhead line must be at least those given in Table. 3.24.
Table 3.24
Distances from wires of overhead lines to the surface of the earth in uninhabited and hard-to-reach areas
The horizontal distance from wires of overhead lines with voltage up to 1 kV with their greatest deviation to buildings and structures should be at least: 1.5 m - to balconies, terraces and windows; 1 m - to blank walls. The passage of the overhead line above the building is not allowed, with the exception of the approaches of the branches from the overhead line to the inputs to the buildings.
Horizontal distances from overhead line supports to underground cables (except for communication, signaling and radio transmission cables), pipelines and above-ground columns for various purposes must be at least:
0.5 m - to cables, but when they are laid in an insulated pipe;
1 m - to water, gas, steam and heat pipelines, as well as sewer pipes;
2 m - to fire hydrants, wells (manholes) of underground sewage, standpipes;
10 m - to petrol stations.
Crossing overhead lines up to 1 kV with navigable rivers is not recommended. When crossing non-navigable and freezing small rivers, canals, the distance from the overhead line wires to the highest water level must be at least 2 m, and to ice - at least 6 m.
When crossing overhead lines up to 1 kV with overhead lines over 1 kV, the intersection should be chosen as close as possible to the support of the upper (crossing) overhead line; at the same time, the horizontal distance from this support to the wires of the lower (crossed) overhead line with the greatest deviation of the wires must be at least 6 m, and from the supports of the lower (intersected) overhead line to the wires of the upper (crossed) overhead line - at least 5 m. Allowed in some cases of crossing overhead lines on a support.
When crossing a 330–500 kV overhead line, the supports of the crossing overhead line must be anchored with a normal design.
The intersection of 330-500 kV overhead lines with 220 kV overhead lines and below is allowed to be carried out on intermediate supports.
During the construction of 330 kV overhead lines and below, they are allowed to pass under the existing 330–500 kV overhead lines in spans limited by intermediate supports.
When crossing overhead lines of 220 kV and below, it is allowed to use intermediate supports on the crossing overhead line.
Higher voltage overhead wires, as a rule, should be located above lower voltage overhead lines. It is allowed, as an exception, the passage of an overhead line of 35 kV and above with wires with a cross section of 120 mm 2 or more above the wires of an overhead line of a higher voltage, but not higher than 220 kV.
It is recommended to cross overhead lines up to 1 kV on cross supports; crossing in the span is also allowed, while the vertical distance between the nearest wires of intersecting overhead lines at an ambient temperature of +15 ° C without wind should be at least 1 m. at the same time, the horizontal distance between the supports of the crossing and the wires of the crossed overhead line must be at least 2 m.
On double-circuit supports, the distance between the nearest wires of different circuits, according to the condition of the wires in the span, must be at least: 2.5 m - for 35 kV overhead lines with pin and 3 m with suspension insulators; 4 m - for 110 kV overhead lines; 6 m - for 220 kV overhead lines; 7 m - for 330 kV overhead lines; 8 m - for 500 kV overhead lines.
Distances between wires or between wires and cables of intersecting overhead lines on metal and reinforced concrete supports, as well as on wooden supports in the presence of lightning protection devices are given in table. 3.25.
Table 3.25
The distance between the wires at the intersection of overhead lines between themselves and with overhead lines of lower voltage
On overhead lines with wooden poles, not protected by lightning protection cables, on the supports that limit the crossing spans, tubular arresters should be installed on both intersecting overhead lines. If the distance from the intersection to the nearest supports of intersecting overhead lines is not more than 40 m, arresters or protective gaps are installed only on the nearest supports.
With parallel passage and approach of overhead lines, the horizontal distances must be at least those indicated in Table. 3.26.
Table 3.26
Horizontal distances between overhead lines
* When 500 kV overhead lines approach each other and with lower voltage overhead lines - at least 50 m.
The intersection of wires of overhead lines with voltage up to 1 kV with LS and RS lines must be performed according to one of the following options:
not insulated wires VL and insulated wires LS and RS;
uninsulated wires of overhead lines and underground or overhead cable LS and RS;
uninsulated wires VL with increased mechanical strength and uninsulated wires LS and RS;
insulated wires of overhead lines and uninsulated wires of LS and RS;
underground cable VL and uninsulated wires LS and RS.
The vertical distance from the wires of the overhead line to the wires or overhead cables of the LS and RS in the crossing spans with the largest sag (highest air temperature, ice) should be at least 1.25 m.
The vertical distance from the wires of the overhead line to the wires or overhead cables of the RS when crossing on a common support must be at least 1.5 m.
The intersection of the wires of the overhead line with wires or overhead cables of the LS and RS in the span should be at a distance of at least 2 m from the nearest overhead line support, but as close as possible to the overhead line support. The wires of the overhead line should be located above the wires of the LAN and RS. In exceptional cases, wires of 380/220 V overhead lines may be placed under the wires of rack-mounted LANs.
When approaching overhead lines with overhead LANs and RSs, the horizontal distance between the extreme wires of these lines must be at least 2 m, and in cramped conditions - at least 1.5 m. In all other cases, the distance between the lines must be at least the height of the largest support of the overhead line , LS and RS.
Joint suspension on common supports of wires of overhead lines, LS and RS is not allowed. Joint suspension of overhead lines and insulated switchgear wires is allowed on common supports.
The vertical distances from the wires of the overhead line to the crossed wires of the LS and RS in the normal mode of the overhead line and in the event of a break in the wires in adjacent spans of the overhead line must be at least those given in table. 3.27.
Table 3.27
Vertical distances from overhead lines to LS and RS wires
The smallest horizontal distance when approaching overhead lines with overhead LS and RS with non-deflected wires should be no less than the height of the highest overhead line support, and in areas of a cramped route with the greatest deviation of overhead lines by wind: 2 m - for overhead lines up to 10 kV; 4 m - for 35 and 110 kV overhead lines; 6 m - for 220 kV overhead lines; 8 m - for 330 kV overhead lines; 10 m - for 500 kV overhead lines.
The angle of intersection of overhead lines with railways electrified and subject to electrification over the next 10 years must be at least 40 °. It is recommended to cross at an angle close to 90°.
When crossing and approaching overhead lines with railways, the distance from the base of the overhead line support to the dimension of the approach of buildings on non-electrified railways or to the axis of the supports of the contact network of electrified roads must be at least the height of the support plus 3 m. On sections of a cramped route, this distance is allowed to take at least: 3 m - for overhead lines up to 10 kV; 6 m - for VL 35 - 110 kV; 8 m - for 220–330 kV overhead lines and 10 m - for 500 kV overhead lines.
Distances from wires to various elements railway - gi when crossing and approaching overhead lines with railways must be at least those given in table. 3.28.
Table 3.28
Distances when crossing and approaching overhead lines with railways
The use of pin insulators in spans of intersections of overhead lines with railways is not allowed. The use of reinforced concrete supports and reinforced concrete stepchildren at the supports limiting the crossing span as reinforcement ground electrodes is prohibited.
Distances when crossing and approaching overhead lines with highways must be at least those given in Table. 3.29.
The vertical distance in normal mode is checked with the largest sag, without taking into account the heating of the wires by electric current.
Table 3.29
Distances when crossing and approaching overhead lines with highways
In all cases of convergence of overhead lines with curved sections of roads passing along the embankment, the minimum distances from the wires of the overhead line to the edge of the road must be at least the vertical distances indicated in Table. 3.29.
The distances from the lower wires of the overhead line to the surface of the water must be at least those given in Table. 3.30. Heating of overhead lines by electric current is not taken into account.
Table 3.30
Distances from wires of overhead lines to the surface of the water, dimensions of ships and alloy
When passing overhead lines along dams, dams, etc., the distances from the wires of the overhead line with the largest sag and the greatest deviation to various parts of the dams and dams must be at least those given in Table. 3.31.
Table 3.31
Distances from overhead lines to various parts of dams and dams
When passing overhead lines along dams and dams along which communication lines are laid, it must also meet the requirements for overhead lines when crossing and approaching the corresponding objects of communication lines.
The largest sag of the overhead line wires should be determined by comparing the sag at the highest design air temperature and with ice.
Dimensions of the intersection of high-voltage power lines and their approach to structures when using BAKh wires
and SIP are much smaller and are determined by the project on the basis of the Regulatory and technical documentation for the design, construction and operation of pilot industrial overhead lines 6-20 kV with BAH wires and the Regulatory and technical documentation for the design, construction and operation of pilot industrial overhead lines 0.38 kV with self-supporting wires AMKA.
| |
2.5.220. The intersection angle of the overhead line (VLZ) above 1 kV between themselves and with the overhead line (VLI) up to 1 kV is not standardized.
2.5.221. The intersection point should be chosen as close as possible to the support of the upper (crossing) overhead line (VLZ). The distances from the wires of the lower (crossed) overhead line to the supports of the upper (crossing) overhead lines horizontally and from the wires of the upper (crossing) overhead lines to the supports of the lower (intersected) overhead lines in the light must be at least those given in table. 2.5.23, as well as at least 1.5 m for VLZ and 0.5 m for VLI.
It is allowed to cross overhead lines and overhead lines with each other and with overhead lines (VLI) up to 1 kV on a common support.
Table 2.5.23. The smallest distance between wires and supports of intersecting overhead lines
2.5.222. Supports of 500-750 kV overhead lines, limiting the crossing span with 500-750 kV overhead lines, must be of the anchor type.
Intersections of 500-750 kV overhead lines with 330 kV overhead lines and below, as well as 330 kV overhead lines and below, are allowed to intersect in spans limited by both intermediate and anchor supports.
Single-column wooden supports of the crossing overhead line, limiting the crossing span, as a rule, should be with reinforced concrete attachments. It is allowed to use single-column wooden poles without attachments and, as an exception, elevated wooden poles with wooden attachments.
2.5.223. When crossing overhead lines 500-750 kV with overhead lines 6-20 kV and overhead lines (VLI) up to 1 kV, the supports of the crossed overhead lines that limit the crossing span must be of the anchor type, the wires of the crossed overhead lines in the crossing span should be:
- steel-aluminum sectional area of at least 70 mm2 for aluminum - for 6-20 kV overhead lines;
- steel-aluminum sectional area for aluminum of at least 70 mm2 or from heat-strengthened aluminum alloy with a sectional area of at least 70 mm2 - for VLZ 6-20 kV;
- aluminum with a cross-sectional area of at least 50 mm2 - for overhead lines up to 1 kV;
- SIP bundle without a carrier neutral wire with a phase conductor cross-sectional area of at least 25 mm2 or with a carrier wire made of heat-treated aluminum alloy with a cross-sectional area of at least 50 mm2.
Wires in crossing spans must be fastened to supports using:
- suspended glass insulators - for overhead lines (VLZ) 6-20 kV;
- pin insulators with double fastening to them - for overhead lines up to 1 kV;
- tension anchor clamps - for VLI.
2.5.224. On intermediate supports of a crossing overhead line with supporting garlands of insulators, the wires must be hung in blind clamps, and on supports with pin insulators, a double wire fastening should be used.
On intermediate supports of an existing 750 kV overhead line, limiting the span of intersection with newly constructed overhead lines up to 330 kV under it, as well as on existing overhead lines up to 500 kV with a cross-sectional area of \u200b\u200bthe aluminum part of the wires of 300 mm2 or more, when constructing other overhead lines under them, it is allowed to leave clamps with a limited sealing strength and drop-down clamps.
2.5.225. Wires of higher voltage overhead lines, as a rule, should be located above the wires of crossed overhead lines of lower voltage. It is allowed, as an exception, the passage of an overhead line of 35 kV and above with wires with a cross-sectional area of \u200b\u200bthe aluminum part of 120 mm2 or more above the wires of an overhead line of higher voltage, but not higher than 220 kV *. At the same time, the passage of an overhead line of a lower voltage over the wires of a double-circuit overhead line of a higher voltage is not allowed.
* In cities and urban-type settlements, it is allowed to pass overhead lines or overhead lines with insulated wires with a voltage of up to 1 kV over overhead lines with a voltage of up to 20 kV.
2.5.226. The intersection of 35-500 kV overhead lines with double-circuit overhead lines of the same voltage, which serve to supply consumers without backup power, or with double-circuit overhead lines, the circuits of which are mutually redundant, should, as a rule, be carried out in different spans of the crossing overhead line, separated by an anchor support. The intersection of 750 kV overhead lines with such overhead lines is allowed to be carried out in one span, limited by both anchor and intermediate supports.
In sections of a cramped route, the intersection of overhead lines with wires with a cross-sectional area of \u200b\u200bthe aluminum part of 120 mm2 or more with double-circuit overhead lines is allowed to be carried out in one span of the crossing overhead line, limited by intermediate supports. At the same time, double-circuit supporting garlands of insulators with separate fastening of the circuits to the support should be used on the supports that limit the crossing span.
2.5.227. The smallest distances between the nearest wires (or wires and cables) of intersecting overhead lines should be taken not less than those given in Table. 2.5.24 at an air temperature of plus 15 ºС without wind.
For intermediate span lengths, the respective distances are determined by linear interpolation.
The distance between the nearest wires of the crossing and crossing overhead lines of 6-20 kV, provided that at least one of them is made with protected wires, at a temperature of plus 15 ºС without wind should be at least 1.5 m.
The vertical distance between the nearest wires of the intersecting VLZ and the intersected VLI at an air temperature of plus 15 ºС without wind should be at least 1 m.
It is allowed to keep the supports of the crossed overhead lines up to 110 kV under the wires of the crossing overhead lines up to 500 kV, if the vertical distance from the wires of the crossing overhead line to the top of the support of the crossed overhead line is 4 m more values given in table. 2.5.24.
It is allowed to keep the supports of the crossed overhead lines up to 150 kV under the wires of the crossing overhead lines of 750 kV, if the vertical distance from the wires of the 750 kV overhead line to the top of the support of the crossed overhead line is at least 12 m at highest temperature air.
Table 2.5.24. The smallest distance between wires or wires and cables of intersecting overhead lines on metal and reinforced concrete supports, as well as on wooden supports in the presence of lightning protection devices
| Span length of the crossing overhead line, m | The smallest distance, m, at the distance from the intersection to the nearest overhead line support, m | |||||
| 30 | 50 | 70 | 100 | 120 | 150 | |
| When crossing overhead lines 750 kV between themselves and with overhead lines of lower voltage | ||||||
| up to 200 | 6,5 | 6,5 | 6,5 | 7,0 | - | - |
| 300 | 6,5 | 6,5 | 7,0 | 7,5 | 8,0 | 8,5 |
| 450 | 6,5 | 7,0 | 7,5 | 8,0 | 8,5 | 9,0 |
| 500 | 7,0 | 7,5 | 8,0 | 8,5 | 9,0 | 9,5 |
| When crossing 500-330 kV overhead lines with each other and with lower voltage overhead lines | ||||||
| up to 200 | 5,0 | 5,0 | 5,0 | 5,5 | - | - |
| 300 | 5,0 | 5,0 | 5,5 | 6,0 | 6,5 | 7,0 |
| 450 | 5,0 | 5,5 | 6,0 | 7,0 | 7,5 | 8,0 |
| When crossing 220-150 kV overhead lines with each other and with lower voltage overhead lines | ||||||
| up to 200 | 4 | 4 | 4 | 4 | - | - |
| 300 | 4 | 4 | 4 | 4,5 | 5 | 5,5 |
| 450 | 4 | 4 | 5 | 6 | 6,5 | 7 |
| When crossing 110-20 kV overhead lines with each other and with lower voltage overhead lines | ||||||
| up to 200 | 3 | 3 | 3 | 4 | - | - |
| 300 | 3 | 3 | 4 | 4,5 | 5 | - |
| When crossing a 10 kV overhead line between each other and with a lower voltage overhead line | ||||||
| Up to 100 | 2 | 2 | - | - | - | - |
| 150 | 2 | 2,5 | 2,5 | - | - | - |
2.5.228. The distances between the nearest wires (or between wires and cables) of intersecting overhead lines of 35 kV and above are subject to additional verification for the conditions of deflection of wires (cables) of one of the intersecting overhead lines in the crossing span at wind pressure in accordance with 2.5.56, directed perpendicular to the axis of the span of this overhead line, and the undeflected position of the wire (cable) is different. In this case, the distances between the wires and cables or wires must be at least those indicated in Table. 2.5.17 or 2.5.18 for the conditions of the highest operating voltage, the air temperature for non-deflected wires is taken from 2.5.51.
2.5.229. On overhead lines with wooden supports, not protected by cables, on supports that limit crossing spans, protective devices must be installed on both intersecting overhead lines. The distances between the wires of intersecting overhead lines must be at least those given in Table. 2.5.24.
On supports of overhead lines of 35 kV and below, when crossing them with overhead lines of 750 kV and below, it is allowed to use IP. At the same time, for 35 kV overhead lines, automatic reclosing should be provided. Spark gaps on single-column and A-shaped supports with wooden traverses are made in the form of one grounding slope and end with bandages at a distance of 75 cm (along the tree) from the attachment point of the lower insulator. On U- and AP-shaped supports, grounding slopes are laid along two supports up to the traverse.
On overhead lines with wooden poles not protected by cables, when crossing them with 750 kV overhead lines, metal parts for fastening wires (hooks, pins, heads) must be grounded on supports that limit the crossing span, and the number of suspension insulators in garlands must correspond to the insulation for metal supports. At the same time, protective devices must be installed on the supports of 35-220 kV overhead lines.
If the distance from the intersection to the nearest supports of intersecting overhead lines is more than 40 m, it is allowed not to install protective devices, and grounding of the wire attachment details on the supports of overhead lines of 35 kV and above is not required.
Installation of protective devices on the crossing supports is not required:
for overhead lines with metal and reinforced concrete supports;
for overhead lines with wooden supports at distances between wires of intersecting overhead lines, not less than: 9 m - at a voltage of 750 kV; 7 m - at a voltage of 330-500 kV; 6 m - at a voltage of 150-220 kV; 5 m - at a voltage of 35-110 kV; 4 m - at voltage up to 20 kV.
The resistance of grounding devices of wooden supports with protective devices should be taken in accordance with Table. 2.5.19.
2.5.230. With parallel following and convergence of overhead lines of one voltage between themselves or with overhead lines of other voltages, the horizontal distances must be at least those given in Table. 2.5.25 and be received by overhead lines of higher voltage. The specified distances are subject to additional verification:
1) not to exceed the neutral displacement of more than 15% of the phase voltage in normal operation of an overhead line up to 35 kV with an isolated neutral due to the electromagnetic and electrostatic influence of an overhead line of a higher voltage;
2) to exclude the possibility of development in the off position of 500-750 kV overhead lines equipped with compensating devices (shunt reactors, synchronous or thyristor static compensators, etc.), resonant overvoltages. The degree of compensation for the working capacitance of the line, the distance between the axes of the overhead line and the length of the approach sections should be determined by calculations.
Table 2.5.25. The smallest horizontal distance between overhead lines
| Sections of overhead lines and distances | The smallest distance, m, at voltage VL, kV | ||||||||
| up to 20 | 35 |
110
. Read and write useful | |||||||
- "Rules for the installation of overhead power lines with a voltage of 6 - 20 kV with protected wires (PU VLZ 6 - 20 kV)" (approved by the Ministry of Fuel and Energy of the Russian Federation)
13. Intersection and convergence of overhead lines with each other, with overhead lines (VLI) up to 1 kV, with overhead lines above 1 kV
13.1. The angle of intersection of the overhead line with each other, with overhead lines of all voltage classes, as well as with overhead lines up to 1 kV, is not standardized.
The intersection point should be chosen as close as possible to the support of the upper (intersecting) VLZ (VL). At the same time, the horizontal distance from the support of the upper (crossing) VLZ (VL) to the wires of the lower (intersected) VLZ, VL 6 - 20 kV with bare wires or VL up to 1 kV (VLI up to 1 kV) with their greatest deviation should be at least 6.0 m. The horizontal distance from the support of the lower (crossed) overhead line to the wires of the upper (crossed) overhead line up to 400 kV must be at least 5 m. For overhead lines of 500 kV and above, the indicated distances must be at least 10 m.
It is allowed to keep the supports of the crossed overhead lines under the wires of the crossing overhead lines, if the vertical distance from the wires of the crossing overhead line to the top of the crossed overhead line is 4 m more than the values \u200b\u200bspecified in 2.5.121 PUE-98.
It is allowed to intersect VLZ with each other, with VL 3 - 20 kV and with VL (VLI) up to 1 kV on a common support.
13.2. When crossing VLZ with VL (VLZ, VLI), anchor supports should be used. It is allowed to use intermediate supports with reinforced fastening of wires on the crossing VLZ.
Single-column wooden supports of the crossing overhead line must be with reinforced concrete attachments; it is allowed to use single-column wooden supports without attachments. Raised wooden supports are allowed to be used as an exception with wooden attachments.
13.3. Higher voltage power line wires should generally be located above lower voltage power line wires.
13.4. The distance between the nearest wires of the crossing and crossing transmission lines is 6 - 20 kV at an ambient temperature of plus 15 degrees. C without wind must be at least 1.5 m, provided that one of them is made with protected wires.
13.5. In the crossing span, the distance between the nearest wires of the crossing overhead line and the crossed overhead line is up to 1 kV at an ambient temperature of +15 degrees. C must be at least 1 m.
13.6. When crossing an overhead line with an overhead line of 35 kV and above, the distance between the nearest wires of intersecting power lines on metal and reinforced concrete poles, as well as on wooden poles in the presence of lightning protection devices at an ambient temperature of plus 15 degrees. C without wind must not be less than those given in 2.5.121 PUE-98.
13.7. When determining the distances between the wires of intersecting power lines, one should take into account the possibility of lightning damage to both power lines and take the distances for a more unfavorable case, if the upper overhead line is protected by cables, then the possibility of hitting only the lower overhead line is taken into account.
13.8. On the VLZ supports that limit the crossing spans, arresters or surge arresters should be installed on both intersecting lines.
It is allowed to use protective gaps or arc protection devices on VLZ equipped with automatic reclosing instead of arresters.
If the distance from the intersection to the nearest supports of intersecting power lines is less than 40 m, lightning protection devices are installed only on these supports.
Installation of lightning protection devices on the crossing supports is not required in the cases provided for in 2.5.122 PUE-98.
13.9. The resistance of grounding devices for arresters, surge arresters, protective gaps and arc protection devices should not exceed those specified in 2.5.75 PUE-98.
13.10. With parallel passage and convergence of overhead lines and overhead lines up to 20 kV, the horizontal distances between them must be at least those indicated in Table. 13.1.
Table 13.1
SMALLEST HORIZONTAL DISTANCE BETWEEN OHL
AND FROM VLZ TO OHL WITH VOLTAGE UP TO 20 KV
13.11. With parallel passage and approach of an overhead line with an overhead line with a voltage of 35 kV and above, the horizontal distances must be at least those given in 2.5.123 PUE-98.
Complain
Section 2. Sewerage of electricity
Chapter 2.5. Overhead power lines with voltage above 1 kV
Crossing and approaching overhead lines to each other
2.5.220. The intersection angle of the overhead line (VLZ) above 1 kV between themselves and with the overhead line (VLI) up to 1 kV is not standardized.
2.5.221. The intersection point should be chosen as close as possible to the support of the upper (crossing) overhead line (VLZ). The distances from the wires of the lower (crossed) overhead line to the supports of the upper (crossing) overhead lines horizontally and from the wires of the upper (crossing) overhead lines to the supports of the lower (crossed) overhead lines in the light must be at least those given in Table 2.5.23, and also not less than 1.5 m for VLZ and 0.5 m for VLI.
Table 2.5.23. The smallest distance between wires and supports of intersecting overhead lines.
It is allowed to cross overhead lines and overhead lines with each other and with overhead lines (VLI) up to 1 kV on a common support.
2.5.222. Supports of 500-750 kV overhead lines, limiting the crossing span with 500-750 kV overhead lines, must be of the anchor type.
Intersections of 500-750 kV overhead lines with 330 kV overhead lines and below, as well as 330 kV overhead lines and below, are allowed to intersect in spans limited by both intermediate and anchor supports.
Single-column wooden supports of the crossing overhead line, limiting the crossing span, as a rule, should be with reinforced concrete attachments. It is allowed to use single-column wooden poles without attachments and, as an exception, elevated wooden poles with wooden attachments.
2.5.223. When crossing overhead lines 500-750 kV with overhead lines 6-20 kV and overhead lines (VLI) up to 1 kV, the supports of the crossed overhead lines that limit the crossing span must be of the anchor type, the wires of the crossed overhead lines in the crossing span should be:
- steel-aluminum sectional area of at least 70 mm 2 for aluminum - for 6-20 kV overhead lines;
- steel-aluminum cross-sectional area for aluminum of at least 70 mm 2 or from heat-strengthened aluminum alloy with a cross-sectional area of \u200b\u200bat least 70 mm 2 - for VLZ 6-20 kV;
- aluminum with a cross-sectional area of at least 50 mm 2 - for overhead lines up to 1kV;
- SIP bundle without a carrier neutral wire with a phase conductor cross-sectional area of at least 25 mm 2 or with a carrier wire made of heat-treated aluminum alloy with a cross-sectional area of at least 50 mm 2.
Wires in crossing spans must be fastened to supports using:
- suspended glass insulators - for overhead lines (VLZ) 6-20 kV;
- pin insulators with double fastening to them - for overhead lines up to 1 kV;
- tension anchor clamps - for VLI.
2.5.224. On intermediate supports of a crossing overhead line with supporting garlands of insulators, the wires must be hung in blind clamps, and on supports with pin insulators, a double wire fastening should be used.
On intermediate supports of an existing 750 kV overhead line, limiting the span of intersection with newly constructed overhead lines up to 330 kV under it, as well as on existing overhead lines up to 500 kV with a cross-sectional area of \u200b\u200bthe aluminum part of the wires of 300 mm 2 or more, when constructing other overhead lines under them, it is allowed to leave clamps with limited strength terminations and drop-down clamps.
2.5.225. Wires of higher voltage overhead lines, as a rule, should be located above the wires of crossed overhead lines of lower voltage. It is allowed, as an exception, the passage of an overhead line of 35 kV and above with wires with a cross-sectional area of \u200b\u200bthe aluminum part of 120 mm 2 or more above the wires of an overhead line of a higher voltage, but not higher than 220 kV. * At the same time, the passage of an overhead line of a lower voltage over the wires of a double-circuit overhead line of a higher voltage not allowed.
* In cities and urban-type settlements, it is allowed to pass overhead lines or overhead lines with insulated wires with a voltage of up to 1 kV over overhead lines with a voltage of up to 20 kV.
2.5.226. The intersection of 35-500 kV overhead lines with double-circuit overhead lines of the same voltage, which serve to supply consumers without backup power, or with double-circuit overhead lines, the circuits of which are mutually redundant, should, as a rule, be carried out in different spans of the crossing overhead line, separated by an anchor support. The intersection of 750 kV overhead lines with such overhead lines is allowed to be carried out in one span, limited by both anchor and intermediate supports.
In sections of a cramped route, the intersection of overhead lines with wires with a cross-sectional area of \u200b\u200bthe aluminum part of 120 mm 2 or more with double-circuit overhead lines is allowed to be carried out in one span of the crossing overhead line, limited by intermediate supports. At the same time, double-circuit supporting garlands of insulators with separate fastening of the circuits to the support should be used on the supports that limit the crossing span.
2.5.227. The smallest distances between the nearest wires (or wires and cables) of intersecting overhead lines should be taken not less than those given in Table 2.5.24 at an air temperature of plus 15 ° C without wind.
Table 2.5.24. The smallest distance between wires or wires and cables of intersecting overhead lines on metal and reinforced concrete supports, as well as on wooden supports in the presence of lightning protection devices.
| Span length of the crossing overhead line, m | The smallest distance, m, at the distance from the intersection to the nearest overhead line support, m |
|||||
|---|---|---|---|---|---|---|
| When crossing overhead lines 750 kV between themselves and with overhead lines of lower voltage |
||||||
| When crossing 500-330 kV overhead lines with each other and with lower voltage overhead lines |
||||||
| When crossing 220-150 kV overhead lines with each other and with lower voltage overhead lines |
||||||
| When crossing 110-20 kV overhead lines with each other and with lower voltage overhead lines |
||||||
| When crossing a 10 kV overhead line between each other and with a lower voltage overhead line |
||||||
For intermediate span lengths, the respective distances are determined by linear interpolation.
The distance between the nearest wires of the crossing and crossing overhead lines of 6-20 kV, provided that at least one of them is made with protected wires, at a temperature of plus 15 ° C without wind should be at least 1.5 m.
The vertical distance between the nearest wires of the intersecting VLZ and the intersected VLI at an air temperature of plus 15 ° C without wind should be at least 1 m.
It is allowed to keep the supports of the crossed overhead lines up to 110 kV under the wires of the crossing overhead lines up to 500 kV, if the vertical distance from the wires of the crossing overhead line to the top of the support of the crossed overhead line is 4 m more than the values \u200b\u200bgiven in Table 2.5.24.
It is allowed to keep the supports of the crossed overhead lines up to 150 kV under the wires of the crossing overhead lines of 750 kV, if the vertical distance from the wires of the overhead line of 750 kV to the top of the support of the crossed overhead line is at least 12 m at the highest air temperature.
2.5.228. The distances between the nearest wires (or between wires and cables) of intersecting overhead lines of 35 kV and above are subject to additional verification for the conditions of deflection of wires (cables) of one of the intersecting overhead lines in the crossing span at wind pressure in accordance with 2.5.56, directed perpendicular to the axis of the span of this overhead line, and the undeflected position of the wire (cable) is different. In this case, the distances between the wires and cables or wires must be not less than those indicated in Table 2.5.17 or 2.5.18 for the conditions of the highest operating voltage, the air temperature for non-deflected wires is taken according to 2.5.51.
2.5.229. On overhead lines with wooden supports, not protected by cables, on supports that limit crossing spans, protective devices must be installed on both intersecting overhead lines. The distances between the wires of intersecting overhead lines must be at least those given in Table 2.5.24.
On supports of overhead lines of 35 kV and below, when crossing them with overhead lines of 750 kV and below, it is allowed to use IP. At the same time, for 35 kV overhead lines, automatic reclosing should be provided. Spark gaps on single-column and A-shaped supports with wooden traverses are made in the form of one grounding slope and end with bandages at a distance of 75 cm (along the tree) from the attachment point of the lower insulator. On U- and AP-shaped supports, grounding slopes are laid along two supports up to the traverse.
On overhead lines with wooden poles not protected by cables, when crossing them with 750 kV overhead lines, metal parts for fastening wires (hooks, pins, heads) must be grounded on supports that limit the crossing span, and the number of suspension insulators in garlands must correspond to the insulation for metal supports. At the same time, protective devices must be installed on the supports of 35-220 kV overhead lines.
If the distance from the intersection to the nearest supports of intersecting overhead lines is more than 40 m, it is allowed not to install protective devices, and grounding of the wire attachment details on the supports of overhead lines of 35 kV and above is not required.
2.5.119. The angle of intersection of overhead lines above 1 kV between themselves and with overhead lines up to 1 kV is not standardized.The intersection point should be chosen as close as possible to the support of the upper (crossing) overhead line; however, the horizontal distance from this support to the wires of the lower (crossed) overhead line with the greatest deviation of the wires must be at least 6 m, and from the supports of the lower (intersected) overhead line to the wires of the upper (crossed) overhead line - at least 5 m. For anchor supports of 500 kV overhead lines, the indicated distances must be at least 10 m (see also).
In some cases, it is allowed to cross overhead lines on a support.
Table 2.5.25.
The smallest distance between wires or between wires and cables of intersecting overhead lines on metal and reinforced concrete poles, as well as on wooden poles in the presence of lightning protection devices
| span length | The smallest distance, m, at the distance from the intersection to the nearest overhead line support, m | |||||
| VL, m | 30 | 50 | 70 | 100 | 120 | 150 |
| When crossing overhead lines 500 - 330 kV between themselves and with overhead lines of lower voltage | ||||||
| up to 200 | 5 | 5 | 5 | 5,5 | - | - |
| 300 | 5 | 5 | 5,5 | 6 | 6,5 | 7 |
| 450 | 5 | 5,5 | 6 | 7 | 7,5 | 8 |
| When crossing overhead lines 220 - 150 kV between themselves and with overhead lines of lower voltage | ||||||
| up to 200 | 4 | 4 | 4 | 4 | - | - |
| 300 | 4 | 4 | 4 | 4,5 | 5 | 5,5 |
| 450 | 4 | 4 | 5 | 6 | 6,5 | 7 |
| When crossing overhead lines 110 - 20 kV with each other and with overhead lines of lower voltage | ||||||
| up to 200 | 3 | 3 | 3 | 4 | - | - |
| 300 | 3 | 3 | 4 | 4,5 | 5 | - |
| When crossing a 10 kV overhead line between each other and with a lower voltage overhead line | ||||||
| Up to 100 | 2 | 2 | - | - | - | - |
| 150 | 2 | 2,5 | 2,5 | - | - | - |
When determining the distances between the wires of intersecting overhead lines, one should take into account the possibility of lightning strike both overhead lines and take the distances for a more unfavorable case. If the upper overhead line is protected by cables, then the possibility of hitting only the lower overhead line is taken into account.
It is allowed to keep the supports of the crossed overhead lines up to 110 kV under the wires of the crossing overhead lines, if the vertical distance from the wires of the crossing overhead line to the top of the support of the crossed overhead line is 4 m more than the values \u200b\u200bgiven in Table.
Table 2.5.26.
The smallest horizontal distance between overhead lines
* When 500 kV overhead lines approach each other and with lower voltage overhead lines - the height of the highest support, but not less than 50 m.
On overhead lines of 35 kV and below, it is allowed to use protective gaps instead of tubular arresters. At the same time, automatic re-closing should be provided for the overhead line. Protective gaps on single-column and A-shaped supports with wooden traverses are made in the form of one grounding slope and end with bandages at a distance of 75 cm (along the tree) from the attachment point of the lower insulator. On U- and AP-shaped supports, grounding slopes are laid along the posts of the U-shaped face of the support to the traverse.
If the distance from the intersection to the nearest supports of intersecting overhead lines is not more than 40 m, arresters or protective gaps are installed only on the nearest supports.
The installation of tubular arresters and protective gaps is not required for:
VL with metal and reinforced concrete supports;
Overhead lines with wooden poles at distances between wires of overhead lines intersecting with each other and with overhead lines of lower voltages, not less than: 7 m at a voltage of 330-500 kV, 6 m at a voltage of 150-220 kV, 5 m at a voltage of 35-110 kV, 4 m at a voltage of 3-20 kV.
The resistance of grounding devices for tubular arresters and protective gaps should be no more than those indicated in Table.
