Energy is considered: the drafting of the production of works in accordance with the SAE. Although the sixth edition of the seventh heavily cropped, today look through the old, to refresh the memory. PUE cause deep respect Masters, the rules prescribed truisms. Most of the text (if not all) agreed with the relevant government authorities. Cable routing is performed in the trench organization able to provide qualified personnel, owning a license.
Route the cables correctly
It is strongly recommended to study the SEP 6, figuring out how to seal the power cable in the trench properly conducted. Document devoid of legislative support (although the agreement was carried out, for the prescription of feather grass overgrown), many organizations are guided by the rows verified until now. Reading the document is complicated by difficult structure. The main observations that need to know the beginner to avoid confusion:
- Under the protected and unprotected cables meant revealing unified definition of standards. Published separately in the Standard CIP. Paper product names protected. So CIP installation carried out by the said PES scheme for protected cables.
- How to work with electrical lines starting section (ejected PUE 7 amended), links are provided to other parts of the rules.
- Parsing start general terms, according to an increase in voltage. Not strictly. For example, all the lines indicate the specific position, complete rules, spiced reservations are on. In the section about the voltage to 220 kV discussed laying cables in the ground points. Violation of chronological order will confuse the beginner, you need to carefully read the section 2, select the relevant existing line (the majority of the inhabitants of 220 or 380 volts, up to 1 kV). Russia introduced the 230 volts after the approval of the text of the SAE 6. Overview VashTehnik portal brings information verbatim.
After reading the SEP 6, say the following concerning cable laying in the ditch ...
depth of the
The cables are laid at a depth of 0.7 meters, a fact demonstrated fairly Youtube videos. In parallel, silent thing: the distance set for a range of cables up to 35 kV. Further, the depth increases to a meter. But not just in relation to the soil, but the planning mark. To the best of our understanding - a sign left by surveyors in the plan to be carried over the terrain. The ground is uneven, it is necessary to find a middle level. The depth of up to 1.5 meters from 110 kV. Rollers Youtube evaluate, making note of criticism.
By plowing cable 6 - 10 kV is placed deep - buried 1 meter. There are some other exceptions to the rule.
Pit for cable
The pit is dug slight outward slant walls. Width is not so important, as requirements for the tab. Put together a maximum of six cables with voltage up to 35 kV. By remaining dig another trench, and so on. The distance between groups is greater than 0.5 meters.
The trench is dug deeper deliberately centimeters by 10. According to the rules for cable poured drainage sand, tamped. No special equipment - craftsmen apply their own feet. Elected method defined front work.
The trench under the cabling is not equipped with a 0.6 meters closer to the base of the building, any other underground engineering construction. Curiously, neither said a word about the blind area (track along the perimeter of the house). Normalized distance trunks of trees - not less than two meters. Indirectly, points out the area of green space runs deprived (in fact, production lines specifically designated by each saw signs: carefully, cable!). Forest uprooted. This distance is reduced when installing the parks, forest belts (agree on the project).
Bookmark steel cable
Further originally defined cable. Have steel armor backfilled with purified (devoid of construction waste ground). 25 cm above the ribbon cable laid insulating material on which is written is held high-voltage line. SEP strongly divergent outlining some practices that these and limited.
It relies on standards to protect the cables from the top, using the special ceramic (for lines up to 35 kV - concrete) slab, brick (for lines greater than 35 kV is unacceptable) from the same material thickness of at least 5 cm. Private exceeds these dimensions. Brick put across the line, tile - as indicated by the manufacturer's instructions. The vertical distance of the cable is 15 cm. For support on the sides along the lines laid out two rows of bricks (one from left to right), put a cross on top.
Note above the ground must be clean cable. Superintendents, tschas find the ground covered with sand. bricks on top of the still tape warning labels moles, special plates include those on the surface. Additional signaling is required. Warning tape for cable laid in the trench theoretically.
Laying the cable armor
Armored cable, according to the written, laid in the ground, other brands need to be protected. You can use the corrugation (for power lines black, red, connected - blue), HDPE pipes. The first is applied in most cases, when roads pass when horizontal drilling is carried out, polyethylene is used more frequently. Much reduces friction and simplifies the process of laying the cable.
When laying depth of 1 - 1.2 meters permitted to do without the protection plates below 20 kV networks (including 220/380). Not place the bricks along, if one cable trench width not exceeding 25 cm. It can save about half the cost of the material. It prohibits the use of silica, hollow brick. Cables voltages below 1 kV allowed to deny protection.
One exception, which can be used for saving. The track is formed of 5 to 20 kV cables (not supply consumers category I). According to the rules to protect slabs, bricks. And here we come up with clever heads divided into three tranches (leaving put two feet), where the cable is placed under the scheme 2h2h1. Laying cables in trenches by said RB refers to the category of exceptions. You can confine laying warning tape. Bricks, slabs constitute a net savings. Increasing the volume of excavation? In CPD for cable laying in a trench involves the use of techniques, leaving a loop (more than half a meter). Bottom podsypaya sand install cables according to the scheme add pure land stacked warning strip.
Flow chart of the work preclude the application of warning tapes cables crossing the area with utilities (water, sewer) to 2 meters on each side, above the collar. Similar demands, but with increasing distance up to 5 meters, there are approaches to distribution boards and substations. Signal tape is laid with a margin of at least 5 cm laterally from the axes of the cables adjacent tapes (with wide route) extend overlap by 5 cm.
Warning tape high-voltage track
Cabling technology trench
It provides restrictions on the horizontal distance between the lines: 10 cm - less than 10 kV; 25cm - 10-35 kW; 50 cm - between the cables, operated organizations, and above 110 kV. However hushed vertical distance (the authors did not find). Some organizations skillfully use the space by mounting a bunch of guys. Each cables are arranged vertically. Can significantly reduce the width of the grooves, avoiding the use of bricks that protect the route. Digging trenches for cabling is simplified, financial costs are reduced.
Parallel conducting cable
Allowed parallel cabling connections in the trench, power lines, utilities. Distance to last at least one meter (up pipelines, heat conductors - 2 meters). Between the cables maintained a distance, according to the instructions above. The distance to the utilities lines can be reduced to 35 kV twice, applying packing in protected form (IPA inside tube), the range does get ridiculous - 25 cm. Are some other exceptions PUE.
cables crossing points
At the intersections cables vertical distance of at least 0.5 meters. Parallel follow silenced! At the junction of the gap size can be reduced by applying concrete slabs, with a supply pipe of one meter each way. communication cable goes above the power lines.
The distance to the grounding
Normalized distance to the earthing of high-voltage lines (breaks under pillars): up to 1 kV - 1 meter; 1-35 kW - 5 meters; above 110 kV - 10 meters.
Cable Management Practice
Painted norm now readers will wonder how techniques are implemented in practice. The depth of the trench cabling is kept private traders tentatively tool will serve as a shovel. Enterprises use tractors equipped with a harrow (cutter), bulldozers (broad removal layer). Cable bit zmeitsya goes light wave. It helps to compensate for temperature changes of the seasons. Trying to put right the big the segment:
- Along the route mounted rollers system repeated bending Krivorukov bulldozer driver.
- Under the highway, ravines being horizontal drilling with the release of the cable channel on the other side. IPA laid inside the tube. Some cable types can be directly cast to the bottom (mesh screen).
- Sometimes used concrete blocks that serve as channels.
Typical project shows the sequence of actions. Suppose, wiring inside the pipe in the trench is carried out by drawing a cable winch. The tension does not exceed 30 N / sq. aluminum mm and 50 N / sq. mm copper wires. Sectional view taken pure metal braid area discarded. Estimated length stretches winch cable segment, are calculated according to the coefficients, the frictional force load. Typical examples of numbers:
- The coefficient of friction when driving on rollers - 0.2-0.3
- When pulling into a concrete box - 0.4-0.6.
- When the dragging of the pipe inside IPA defined procedure (lowering rate used grease, oil, water). It ranges from 0.1 - 0.25.
Load three braided cable is calculated ratio, if one stretches. No one is unable to ensure that the length of the elements are exactly the same. In practice and difficult to reach. The radius of curvature of a single cable should be greater than 15 times the diameter of external insulation. For three-core - 12. It is not enough to learn the types of cabling trenches, read PUE. It needs to explore the many norms, standards, rules, regulations.
Laying cables vzaimorezerviruemyh trench PUE such is not prohibited. But the introductory part saying lines in one arm mounted banned. In the case of force majeure may occur simultaneous failure of one or the other line (arc melt). The root cause for which the joint laying of cables is not welcome.
We finish the review, we hope, we explained how to use the documents. Entirely occasions not provide advice. Practical examples are, projects implemented commissioned. to use loopholes in the law should not be too hard. Suddenly changed!