Sip cable installation technologies. Installation of fiber optics along outdoor lighting poles. Underground method from a pole.

Introduction

Hello, dear readers of the site Elesant.ru. Today I want to talk about attaching the cable to the support when lowering it into the trench. For attaching the cable to the support, a variety of special devices, and connecting the cable to the overhead line is regulated by a number of regulatory documents. This is exactly what this article will discuss.

A variety of special devices are produced for attaching the cable to the support, and connecting the cable to the overhead line is regulated by a number of regulatory documents. This is exactly what this article will discuss.

After preparing the trench, to introduce power into the house, lay the cable into it, and insert the power cable from the trench into the house, you need to secure the cable to a support and connect the input cable to the overhead line.

Attaching the cable to the support

When lowering the cable into a trench, starting from 2 meters above the ground, the cable must be protected with a pipe. The pipe should rise along the support, bend at an angle of 90° and protect the cable in the trench for a meter.

Here I would like to dwell on the established bending radii of pipes when laying electrical cables in them

When bending pipes, the bending angle and bending radius are standardized. Bend angle metal pipes for laying electrical cables in them, it is standardized at 90°, 120° and 135°. The bending radius directly depends on the cross-section electric cable, and accordingly the diameter of the pipes for electrical wiring. See the figure for bending radii.

Well, the supports are higher than two meters, and you need to connect to the overhead line almost at the top of the support, leaving some section of the cable without protection. You can protect it with a simple metal corner (see photo below, arrow 10) with shelves suitable for the cable diameter.

The figure below shows an example of running and securing the cable to the terminal support. The overhead line in the figure is made of insulated SIP wires. By the way, such a line is designated VLI (insulated overhead line).

The SIP overhead line wire is attached to the support with an anchor tension clamp (8). The anchor tension clamp is secured with a loop to the anchor bracket.

The cable going down into the trench has metal protection and armor. The most popular cable for laying in trenches is VBBShV. The metal cable protection must be grounded. (PUE, Chapter 2.4) To do this, the PEN conductor of the overhead line is connected to the flatbed clamp (4) and the ground wire using a piercing through clamp (7).

All fastenings to the support are made with mounting crimping tapes (2). The crimping tape is tightened with a special clamp (lock) (3).

The place where the cable is separated and the armor and insulation is stripped is protected by a heat-shrinkable sleeve, a “glove” (6).

1.Anchor bracket;
2. Mounting crimping tape;
3. Clamp for fastening the mounting tape;
4. Tablet clamp for connecting ground wires;
4a. Wire grounding the armored coating of the cable;
5. Heat-shrinkable protective cuff, “glove”;
6. A clamp that pierces the passage with a branch. Connects the PEN conductor to the ground wires;
7. Anchor tension clamp for SIP wires;
8. Cable bandage strap; Insulating cap;
9. Protective cap for the wire;
10. Metal corner to protect the cable to the pipe.

There are many types of fastening the cable to a support when lowering into a trench, but I described the principle of lowering and fastening the cable to a support above.

The same mounting tapes can be used to secure the input device, electric meter and any other electrical equipment to the support.

Section: Home connection

Social buttons for Joomla

elesant.ru

Technology for installation and repair of SIP wires on supports

For construction and renovation modern lines power transmission lines have been using SIP wires for a long time. They are highly reliable and rarely require repairs. Often, preventive measures or just an examination are sufficient for VLI. Today, insulated wire has become widely used not only for the construction of highways, but also for connecting the building input.

Cable installation on poles

Overhead power lines with SIP wires are called VLI. Their installation traditionally begins with clearing the area of trees, bushes, and other possible obstacles that interfere with rolling out and tensioning the wires on the supports.

When building a new power line, it is more convenient to attach the brackets for the wire to the pole on the ground before installing it. The brackets are fastened to the supports using a clamp made of corrosion-resistant steel tape. After tightening, excess tape is removed.

The poles with mounting brackets are installed and the installation of overhead power lines begins. Installation of SIP on supports takes place using components at an outside air temperature of at least 20°C. SIP installation technology has its own peculiarity associated with wire rolling. It protects the insulation from damage. The wire is rolled out from a drum installed on the machine. SIPs are distributed on the supports using rollers and a tension rope - leader.

Manual wire rolling

The technology for unwinding from a SIP coil involves manual execution of the process, provided that the area is limited to one hundred meters and the cross-section of the phase conductors does not exceed 50 square meters. mm. It is allowed to manually roll out the wire in populated areas, where the span length does not exceed 50 m. The manual rolling technology has the following sequence:

At this stage, the installation of SIP in one span is completed. The following spans are mounted using a similar method.

Cable connection

Having laid the self-supporting wire on the supports, you need to connect it to the main power line and lead from it to the house:

Connecting the building input to the main line

Connect the house input to the common highway with your own hands better cable SIP-4. A self-supporting wire consists of four cores of the same cross-section twisted together. There are two ways to enter a house.

Ground method from a pillar

The ground method involves connecting the internal wiring of the house to the nearest pole. The support should not be located further than 25 m from the building, otherwise you will have to install an additional pole near the house at a distance of 10 m. Between the poles, the wire supplying electricity to the house must be at least 6 m from the ground.

Do-it-yourself connection of a self-supporting wire to the main line is done using clamps. But first you need to lay out the SIP along the wall of the house. To keep the wire firmly on the facade, anchor clamps are attached to the wall. They are a bracket with a loop, attached to the wall with a dowel. To secure the cable, you just need to tighten it with this loop. Installing brackets on the wall requires compliance with safety rules, according to which the distance between the fasteners and the ground must be at least 2.75 m.

Next comes the input street cable to the house. If switch box installed on the external wall of the house, then the SIP cable is connected only to it. Connecting the internal wiring to the panel is done with a VVGng cable. It is more elastic and smaller in diameter. The location of the electrical panel inside the house will require entering the SIP through the wall, although many electricians recommend taking the panel outside and leading the VVGng cable from it into the house. SIP is allowed to be used for external and interior work, so it’s easier to immediately bring it inside the house. Only in the wall where the SIP will be installed, you need to install a metal sleeve.

When all communications have been laid, all that remains is to connect the input to the main line on the pole. Do-it-yourself connection is done in this order:

Anchor brackets are attached to the wall of the house and the pole.
Near the house, the wire is secured with a clamp to the bracket.
The SIP roller block is pulled between the building and the pole.
The edge of the cable on the pole is fixed with a clip with a loop, putting it on the anchor bracket.

Now all that remains is to connect the outlet cable to the common line with suitable clamps.

Underground method from a pillar

Connecting the input underground is more important, since the wire is protected negative influence atmospheric phenomena, fire and accidental breakage. Underground installation occurs in the following order:

Input cable lowered from the pole into a trench dug towards the house. The minimum depth of the trench is 80 cm. The area under the road is deepened to 1 m.
In a trench, SIP is placed in a metal or plastic sleeve. The same sleeve should come out of the ground up a column, at least 2 m high;
At backfill trenches on the surface install signal beacons warning of the passage of the cable.

The cable entry into the house is done under the foundation through a sleeve or raised along the wall, if switchboard is located on the street.

SIP repair

During operation, the wire may become damaged in certain areas, which will require repair. For phase or neutral conductors repair small area damaged insulation is carried out without removing the voltage. The damaged core is separated from the common bundle with plastic wedges and a double layer of adhesive insulation is applied to it, after which the wedges are removed.

Repair of a phase conductor with a length of no more than 2 m per span is carried out without replacing the entire bundle. The damaged section of the core is separated with wedges and replaced. To do this, take a piece of wire of a similar brand and cross-section and insert it in place of the damaged section. The ends are connected using branch clamps. It is possible to use a piercing clamp without removing the insulation.

A long section of damaged wires is repaired after a power outage. The span with the section requiring replacement is grounded on both sides. The cable is disconnected at all branch terminals and lowered to the ground using ropes. Further repairs consist of replacing the damaged section, after which the entire span is raised onto supports for connection to the main line.

Repair of the branch to the house is done when more than 20% of the wire of its total length is damaged. Work can be carried out with or without voltage, but the consumer load must be disconnected. The input cable is disconnected at the branch terminals. The phase conductor on the support is disconnected first, and then the neutral conductor. The end of the wire is tied to a support to prevent it from falling. Having freed it from the anchor bracket, the SIP is lowered with a rope to the ground, where it is repaired. Lifting onto the support and connecting to the main line occurs in the reverse order.

Correct installation SIP, timely identification of the damaged section of the cable and its repair will ensure uninterrupted supply of electricity to the consumer.

sarstroyka.ru

Cable installation on supports and poles

When building networks, telecom operators are often faced with the inability to use cable duct or buildings. For passage using the air suspension method, in such cases, installing the cable along lighting poles or power poles can greatly facilitate the task. There are several standard installation methods: 1. Supportive. 2. Tension.3. Combined. Let's take a closer look at each of the methods.

1. Installation of the optical cable using support clamps.

Support clamps are used for areas where the cable runs in a straight line, the maximum angle of rotation when using such clamps is from 10 to 20°. Domestic and foreign manufacturers offer a variety of clamp options to support the installation of ADSS and figure-8 cables.

Clamps PPO-6.5/8.0-06 or ZP-8-1(2)

PPO or ZP clamps can be used on routes with the risk of trees falling or damage to poles. If a tree falls on the cable or the pole is damaged, the cable breaks out of the clamp and usually remains undamaged. Examples of using PPO clamps in combination with various fastening units.

Spiral supporting clamps.

Spiral clamps are used for mounting self-supporting cable(ADSS) on power transmission poles, lighting and communication poles. Many modifications are available for different span lengths and cable termination strengths. The fastener consists of a protector - to protect the cable sheath from damage, a power spiral and a thimble.

Supporting clamp SC30/34 or CS Universal clamp for hanging “8-shaped cables”, can be fastened with a steel tape or with a bolt on wooden supports. Allows installation of cables with a cable diameter of 4 to 9 mm.

It is characterized by simple and quick installation, but has a number of limitations. When using such clamps, it is important to accurately select the diameter of the cable; in practice, there have been cases of the cable slipping through the clamp; it is also important to strictly observe the recommended span length. The practice of using such clamps has shown that they are best used in combined version installation (Alternating anchor and support clamps).

Supporting clamp NS 10/15.

NS 10/15 clamps are used for mounting ADSS cables with a diameter of up to 20 mm; it is recommended to use them on straight sections of the route.

Based on experience in use, we can say that such clamps are good for short spans - up to 60-70 m; installation during rain is practically impossible, since the cable slips through the bushing.

2. Cable installation optical using tension clamps. Tension (anchor) clamps are used for rigid cable fastening; they are used both at rotary, branch, end sections of installation, and along the entire length of the route.

Tension anchor clamps AN-250(500,700,800), AC 6(7), PA 06(07),

Anchor clamps can be used with both “8-shaped” and self-supporting cables. Cable suspension clamps with load-bearing element made of steel cable allow you to quickly install the cable, without stripping and separating the power element. Plastic loop on the clamping cable ensures insulation of the load-bearing element in the event of a short-circuit to ground of the support. It is NOT recommended to use such clamps when installing cables with power element made of steel wire, under long-term load, the teeth of the wedges begin to slip along the smooth wire, which leads to damage to the cable.

Tension spiral clamps.

Tension spiral clamps are used for installation of self-supporting cables (ADSS) on power line supports, power poles, lighting, and railway contact networks. The fastener consists of a protector, a loop-shaped power spiral coated with a special abrasive and a thimble.

3. Installation of optical cable using the combined suspension method.

The combined suspension method is widely used when using PPO clamps, SC30\34. The essence of the method is alternating support and tension (anchor) clamps. In this way, the reliability of the line can be increased and construction and operating costs can be reduced. The optimal ratio is 4 support clamps to one tension clamp.

lanset.ru

Technology for installing SIP-3 wires on 6-10 kV overhead line supports.

The length of 6-10-20 kV overhead lines made with SIP-3 wires is growing every year. Such lines are called VLZ for short - which means overhead lines with protected wires. Do not confuse with VLI-0.4 kV - overhead lines with insulated wires, where SIP-1, SIP-2, SIP-4 are used for low voltage 220V-380V.

It is the average voltage class of 6-10 kV that accounts for the main share of emergency shutdowns. Old 6-10 kV power lines made with bare wires are primarily susceptible to the influence of weather factors such as wind and ice. And the use of self-supporting wires with protective insulation can significantly improve their safety and reliability characteristics.

When using SIP-3, several parameters are reduced at once:

space when arranging distribution units at a substation

All this is very beneficial from an economic point of view.

Technical specifications and characteristics (section, rated current, short-circuit current, diameter, weight) of high-voltage wire SIP-3:

More data - current, active, inductive reactance, voltage drop

The quality of the overhead line certainly depends on the quality of the wires used, but it equally also depends on the fittings used. When using proven materials, it is possible to build a maintenance-free overhead line with a service life of more than 40 years.

The SIP-3 wire can be mounted both on new supports and on existing ones, instead of bare AC-50-70-95-120 wires. Naturally, with the replacement of all load-bearing, fastening fittings and insulation. Replacing an old 10 kV overhead line with a new overhead line with SIP-3 wires is called reconstruction.

Both reconstruction and new construction must be carried out according to the project.

Most often, the installation of a new overhead line begins with the installation of anchor supports. Even before the rise of the anchor support post, on the ground, they fix it required amount traverse.

To prevent corrosion, and also because the line must be maintenance-free, it is necessary to use galvanized crossbars. Otherwise, in a few years you will have to re-climb each support and repaint the faded cross-arms to protect them from rust.

The traverse is immediately grounded. This is done by connecting a die clamp and a steel rod with a diameter of at least 10 mm (section 78.5 mm2) to the grounding outlet at the top of the support.

On reinforced concrete supports, both welded and bolted connections are allowed. On wood, it is recommended to use dies first.

On multi-post anchor supports, the number of grounding descents must be at least two. As such, you can use elements of longitudinal reinforcement of reinforced concrete racks SV-105-110.

All metal structures here (the strut fastening, the traverse itself) are grounded from above, through the grounding outlet. There is no need to make a separate descent made with a rod or strip, directly along the body of the support to the ground.

It is advisable not to screw the insulators onto the traverse onto the ground until the support is installed, in order to avoid accidental damage and damage during installation with special equipment. A partially equipped rack is installed at the desired point using a truck crane or a drill crane machine.

Then one or two struts are installed. Their number depends on the route layout and is determined by the project.

The support must be buried at least 2.3-2.5 meters. After this, intermediate supports are installed.

When all the supports are exposed, you can begin installing insulators on them. Moreover, here you can use both traditional porcelain insulators ШФ-20, and insulators of the new generation IF27 with a special plastic sleeve.

IF27 is more convenient to install and allows you to roll out SIP-3 wire without the presence of mounting rollers. Insulators are mounted on traverse pins or on support hooks using plastic caps KP-22.

However, it is not necessary to use it everywhere modern brands insulators. For example, on anchor supports for VLZ lines with SIP-3, the old time-tested glass insulators PS-70E, collected in garlands of at least 2 pieces, have proven themselves very well.

Technical characteristics of insulators from Ensto, Sicam, Niled for SIP-3:

After installing the insulators, they begin to roll out the wires. The easiest way is to roll out and install directly along the grooves of the IF27 pin insulators.

If simple ShF-20 insulators are used, then you will need unrolling rollers, which must be installed on the cross-beams of the intermediate supports.

A power roller of a slightly different design with a bandage tape is attached to the initial anchor support. If the intermediate crossbars do not have loops or a hook from which the roller could be hung, then devices with bandage tape are used everywhere.

Technical characteristics and brands of mounting rollers from Ensto, Sicam, Niled, KVT:

In front of the very first support, a drum with SIP-3 wire is installed on a cable trolley or on a cable jack.

Rolling out from the drum should be done in such a way as to prevent the wire from touching the ground and the support posts. A leader rope is used for this. It must be made of synthetic rope with a minimum diameter of 6mm.

A standard drum from Ensto ST204.2060-0030 easily fits 1100 m of such cable.

Basic requirements for the rope:

low susceptibility to stretching

UV and moisture resistance

If the length of the cable is not sufficient, then it can be spliced together with special connecting brackets.

The ST204 motorized winch is secured to the final anchor support. A drum with a leader rope is placed on it.

The motor winch provides ease of installation and reduces the total operating time several times.

The portable sheeting machine is installed using a belt or chain banding device.

The leader cable is first pulled through the mounting roller on the final support, and then sequentially through the intermediate supports, pulling it along the grooves of the pin insulators.

Roll out SIP-3 directly onto insulators on intermediate supports possible if the angle of rotation of the route does not exceed 15 degrees.

The rope stretched across the entire anchor section is connected to the wire using a mounting stocking. The leader rope is simply tied with a compact knot directly to the loop of the mounting stocking. At the same time, unlike low voltage wires SIP-4, a swivel for SIP-3 does not need to be used.

The edge of the stocking is wrapped with turns of electrical tape to prevent it from slipping.

One of the installers uses the radio to give a command to the other, who controls the winch, to turn it on. He must also constantly monitor the passage of the cable-to-wire connection along the entire line. And if a wire gets stuck, immediately give the command to stop the winch.

The SIP wire must be pulled evenly, without jerking, at a speed of less than 5 km/h. When rolling out, do not allow the wire to touch the ground and support posts.

When SIP-3 has passed through the last power mounting roller on the end anchor support, the motorized winch is locked. The end of the wire is fixed in an anchor wedge clamp, for example DN Rpi or SO255.

Technical characteristics and brands of anchor clamps from Ensto, Sicam, Niled:

Piercing clamp for electrical connection cable loop with wire, installed later, after the final tension of the line.

The technician on the support removes the wire from the mounting roller and disassembles the connection unit with the leader rope. Now you need to pull out and at the same time adjust the tension of the wire. This should be done with the obligatory use of a dynamometer in accordance with the installation tables. You can download it from here (from page 13).

The method of adjusting the tension of SIP without a dynamometer, guided only by the sag arrows, is not entirely correct.

The error in this case can reach significant values. Everything will depend not on the instruments, but on the eye of the particular installer. The human factor will play a significant role here, which is not at all correct.

The wire must be pulled using a hand winch from the cable drum side.

To do this, a little wire is wound from the drum, a frog mounting grip is attached to it, to which a dynamometer is in turn attached. And the hook of the hand winch clings to it.

The other hook of the winch is hooked to a reliable anchor on the ground. You can use a truck bumper as it.

The excess of wire tension should be no more than 5% of the value indicated in the installation table.

After tensioning SIP-3, the electrician at the support anchors the wire wedge clamp.

After which he immediately installs a branch piercing clamp with a cable for output electric potential wires to the clamp body. This is done to reduce the level of radio interference created by the overhead line and to prevent damage to the insulation of the self-supporting insulation system itself.

After this, you can cut the wire on the support in the right place, leaving the necessary margin and loop for further connection or connection with another SIP-3, or overhead line, cable line 6-10 kV.

Rolling and tensioning of the second and third wires is carried out in a similar way.

Now you need to secure the wires to the intermediate supports. To do this, the plastic bushing on the insulator is rotated so that the slot moves and SIP-3 is tightly closed on all sides.

Fastening occurs with spiral ties.

They are mounted 2 pieces on each insulator, on one side and the other from the traverse.

To choose the right spiral knitting, consider the following two parameters:

For most manufacturers, the dimensions of the knittings corresponding to a certain cross-section of the wire can be determined by color coding.

Technical data for spiral knits from Ensto, Niled, Sicam, KVT:

Ordinary cores aluminum wires Brands such as A-50, A-70 are prohibited from being used here! Spiral knits have a special polymer coating, designed to protect SIP insulation from mechanical damage.

At this point, the direct installation of SIP-3 wires can be considered complete. All that remains is to place lightning protection equipment, switching and other equipment on the supports, followed by supplying voltage from the power source.

Routing for installation of SIP-3 wires - download

domikelectrica.ru

If, when laying a communication line, it is impossible to install it through sewer lines, then installation is carried out through the air, using the so-called “atmospheric” types of cables. They have polyethylene or polyvinyl chloride insulation.

Laying along the pillars is carried out strictly according to technical specifications the cable itself. The distance between the poles should be carefully maintained, and the cable fastening on the poles is made using a “glass” type of connection, with the possibility of additional clamping (in winter and summer the clamp is adjustable, since the cable depends on the temperature environment can be stretched and released).

The power cable for laying along poles has an aluminum or copper core. The first option is cheaper, but the cable has greater resistance than when using a copper core. A VSG brand power cable with a steel core can also be used for laying on tables. The latter type can withstand high mechanical loads (wind, hurricane, gusts), and is multi-level (two or more layers of insulator).

To attach the cable to wooden posts, a PPO type connection is used, with rubber gasket. This connection is adjustable, the cable thickness can be from 0.3 centimeters to 5 centimeters. The most important thing is to provide reliable fastening to the very support.

When using a PPO type connection, the cable is moving. A non-moving fastener is installed every 5-10 supports so that the cable can be tensioned.

Optical power cables are attached to the supports using open-type anchor clamps. At the same time, the pillars themselves are necessarily concrete, of the deployed type. The mass of the cable that must be supported is calculated over the entire length of the span.

Also, to transmit electricity through the air, a universal Multi-Wiski cable is used for laying on tables, which has a galvanized support cable and polyethylene-based insulation. Such cables are well protected from moisture. The advantages of such a cable include ease of installation and installation. The cable adjusts its tension independently, so there is no need to make descents between the pillars. As a rule, both phase and neutral are mounted in one cable, which allows more efficient use of the free area of the pole mounting.

In the event of a break in the overhead cable, it is connected with the same type of cable, the fastening is anchor. If a break occurs between the pillars, then the entire span is replaced, the cable connection is made directly on the pillar. Usage different types In this case, the cable is also prohibited in order to avoid a drop in resistance. Also, laying the power cable along the poles requires maintaining the same resistance of the conductor from the supply station to the final destination (or transformer).

When building networks, telecom operators are often faced with the inability to use cable ducts or buildings. For passage using the air suspension method, in such cases, installing the cable along lighting poles or power poles can greatly facilitate the task.

There are several standard installation methods:
1. Supportive.
2. Tension.
3. Combined.

Let's take a closer look at each of the methods.

1. Installation of the optical cable using support clamps.

Support clamps are used for areas where the cable runs in a straight line, the maximum angle of rotation when using such clamps is from 10 to 20°. Domestic and foreign manufacturers offer many options for clamps for supporting installation of self-supporting (ADSS) and figure-8 cables.

Clamps PPO-6.5/8.0-06 or ZP-8-1(2)

PPO or ZP clamps can be used on routes with the risk of trees falling or damage to poles. If a tree falls on the cable or the pole is damaged, the cable breaks out of the clamp and usually remains undamaged.

Examples of using PPO clamps in combination with various fastening units.

Spiral supporting clamps.

Spiral clamps are used for mounting self-supporting cable (ADSS) on power transmission towers, lighting and communication poles. Many modifications are available for different span lengths and cable termination strengths. The fastener consists of a protector to protect the cable sheath from damage, a power spiral and a thimble.

Support clamp SC30/34 or CS

A universal clamp for hanging “8-shaped cables”, can be fastened with a steel tape or with a bolt on wooden supports. Allows installation of cables with a cable diameter of 4 to 9 mm.
It is characterized by simple and quick installation, but has a number of limitations. When using such clamps, it is important to accurately select the diameter of the cable; in practice, there have been cases of the cable slipping through the clamp; it is also important to strictly observe the recommended span length. The practice of using such clamps has shown that it is best to use them in a combined installation option (Alternating anchor and support clamps).

Supporting clamp NS 10/15.

Clamps NS 10/15 used for installation of ADSS cables with a diameter of up to 20 mm, recommended for use on straight sections of the route.
Based on experience in use, we can say that such clamps are good for short spans - up to 60-70 m; installation during rain is practically impossible, since the cable slips through the bushing.

2. Installation of the optical cable using tension clamps.

Tension (anchor) clamps are used for rigid cable fastening; they are used both at rotary, branch, end sections of installation, and along the entire length of the route.
Tension anchor clamps AN-250(500,700,800), AC 6(7), PA 06(07),
Anchor clamps can be used with both “8-shaped” and self-supporting cables. Clamps for hanging cables with a supporting element made of steel cable allow you to quickly install the cable, without stripping and separating the power element. The plastic loop on the clamp cable provides insulation of the load-bearing element in the event of a short-circuit to ground of the support. It is NOT recommended to use such clamps when installing a cable with a strength element made of steel wire; under long-term load, the teeth of the wedges begin to slip along the smooth wire, which leads to damage to the cable.

Tension spiral clamps.

3. Installation of optical cable using the combined suspension method.

For laying fiber-optic lines along supports are used in cases where it is impractical (or impossible) to use a gasket in the sewer or the trench method. During the construction of intra-zonal and backbone optical networks, the use of optical cable in a lightning protection cable has become widespread - this is the most convenient and reliable way suspensions of fiber-optic communication lines on power lines with a voltage of 110 kV and more. On intrazonal and local lines, self-supporting cable suspension with fastening on the lower crossarm is also used. This option is used both on power lines with a voltage of 110 kV and above, and on air lines less high voltage(10 kV and below) along with low-voltage lines, lighting lines, supports of railway contact networks.

The advantages of laying fiber optic lines along supports include a reduction in construction time along with a reduction in capital and operating costs (there is no need for land acquisition and approvals from interested organizations), a reduction in the scale possible damage in urban areas and industrial zones, as well as independence from soil types.

And although aerial laying of optical cables is much simpler than underground, it is necessary to note the following disadvantages of laying: FOCL on supports, such as a reduction in service life due to environmental influences, susceptibility to increased mechanical stresses under adverse weather conditions, as well as the complexity of calculations when exposed to loads in different conditions operation.

For laying fiber-optic lines by suspension to supports in populated areas, suspension is often used fiber optic cable To steel cable, which is stretched between the supports on the consoles. Fiber optic cable suspension with a built-in cable on specially designed consoles is also used.

When the fiber optic cable is suspended from a steel cable, each console is attached to a support using special screws. Taking into account the normal sag, the installation height of the consoles should be such that the distance from ground level to the lowest point of the cable is 4.5 m or more. The fiber optic cable is attached to the cable using hangers made of galvanized sheet steel. Such hangers must move freely along the steel cable and tightly enclose the fiber optic cable.

In the case of hanging a fiber optic cable, which has a built-in support cable, standard electrical fittings and a supporting clamp are used. For tension fastening For self-supporting fiber optic cables, spiral clamps are used (reinstallation of spiral tension and support clamps is prohibited).

As mentioned above, among the disadvantages of laying fiber-optic lines along supports is the difficulty of calculating all the loads acting on the air-cable transition. As for the calculation of the supporting cable, it includes the calculation of the actual tensile force under operating conditions (it should not exceed the ultimate tensile strength of the cable) and the calculation of the expended length of the cable. Such characteristics of the cable as its ultimate tensile strength and specific gravity are indicated in the manufacturer's technical documentation. When calculating the cable tension, it is necessary to take into account all components of the load that can affect its stretching in real conditions; therefore, it is necessary to calculate its total weight load. Indeed, in the worst case, the cable can stretch under the influence of the vertical component of the load (the cable’s own weight, the weight of the cable and fastening structure, as well as the weight of ice freezing in winter). In addition, the load on the cable can increase under the influence of the horizontal component of the load (wind force). Thus, the expended length of the cable must be calculated taking into account the sag, and it can change depending on fluctuations in tension force and temperature.

The latter should also be taken into account when choosing a design. coupling as well as the size and design of the splice cassette. Temperature fluctuations lead to changes in cable length. This can either lead to the appearance of macrobends in the splice cassette.

The construction of networks involves their installation and laying. If possible, experts prefer to use the underground (trench) method. But if this is not possible, all that remains is to lay the telephone cable along the poles.

Laying on pillars: rules, opportunities, amenities

Laying telephone cable along poles is a less expensive, simple and convenient form of tensioning communication wires. Today there are several standard installation methods:

supporting - made using supporting clamps where the cable runs only in a straight line. The rotation angle should not exceed 10-20 degrees;
tension - requires the use of tension clamps of rigid fastening, used for rotary, circular installation sections, as well as throughout the entire route. The method is convenient due to its efficiency; it does not require additional stripping of the ends, allowing installation to be carried out quickly and without additional tools;
the combined method is used where the route is laid both on straight lines and on corner, turning, and circular sections. Most convenient in high traffic conditions air flow, as it provides a reliable and durable fastening.

It is worth noting that the combined method significantly reduces the financial costs of repairs and construction.

The convenience of laying telephone cables along poles is that:

no need to open the road surface;
you can “hang” the system in dense urban areas,
financial savings.

In addition, external broaching is convenient to operate and repair: you can always see where the break occurred.

Cables for indoor installation (, TCPPt) are intended for local subscriber access networks. Like all systems used internally, they differ:

fire safety,
high quality transfers,
interference protection,
flexibility,
increased strength.

Cables: characteristics

TCPPt cables are telephone wires successfully used for local networks. Installation is carried out in a suspended manner. Rated voltage no more than 225V alternating current and up to 200V DC. Transfer speed up to 2048 kbit/s. Structure of TCPPt:

current-carrying conductor - soft copper wire;
insulation - polyethylene film up to 0.2 mm. thick;
one pair of insulated cores, different in color, is twisted with unidirectional twisting in unequal and non-multiple steps;
galvanized steel wire - load-carrying cable;
The common sheath for the wire is light-stabilized polyethylene.

The system is installed at temperatures from -50 to + 60C, the minimum possible bend is 10 cable diameters, the service life is up to 25 years.

TPPSht cables: characteristics

Underground workings, data transmission from mines - all this is impossible without TPPSht cable. In addition, wires are successfully used for ground installation of the system. Ability to work under extreme conditions low temperatures(up to -60C), flexibility and high reliability of communication have made the wires popular in conditions of increased aggressiveness of the environment. Design elements:

copper wire strand,
polyethylene insulation,
aluminum polymer tape - screen,
galvanized steel wire - support cable,
PVC plastic compound - outer shell.

The right choice of cable for communication is uninterrupted provision where it is really needed.