When constructing new facilities and reconstructing old ones, with an increase in the number of electricity consumers, the construction of power lines with high performance indicators is required. The cable is suitable for laying new routes; it meets all modern standards and requirements for current transmission and distribution. The conductor is often used in areas with cold winters, when the air temperature can drop to -40 degrees.
The advantages of the cable include long service life, resistance to aggressive environments and mechanical stress. If all GOST and PUE requirements for acceptance, storage, installation and operation are met, the wire can be used for 30-40 years.
The most popular conductors include SIP-3 wires with cross-sections of 1x50, 1x70, 1x95. Foreign analogues include SAX and PAS wires.
Wire design
The structure of the SIP-3 cable does not involve the use of a zero load-bearing element. It includes:
- The current-conducting part is made of AlMgSi wires, while its own weight is evenly distributed over the cross-section and length.
- Insulation coating, which is represented by light-stabilized cross-linked polyethylene PEX.
The insulation material has the same technical qualities as solids. Indicators such as resistance to destructive factors and service life are higher for polyethylene. The positive features of the insulator include:
- resistance to high temperatures, including boiling water;
- high dielectric qualities;
- not biodegradable;
- cracks do not appear due to temperature changes;
- excellent tensile and tensile strength;
- not exposed to chemically aggressive substances.
What errors occur when laying SIP-3
Below are the main problems that arise when laying wires:
- Rolling out the wire on the soil. When rolling out, do not allow the cable to lie on the ground - there are special supports for this. Otherwise, the outer layer of insulation can be damaged, which will reduce the service life of the product;
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Rolling process on supports
- Repeated use of piercing fixators. These parts are used to branch the cable from the main line to the consumer. The use of piercing clamps helps to perform branching without removing the outer shell, but such products are used only once;
- Twisting the cable. It is prohibited to twist several SIP wires into a common core. Each cable is laid and installed separately;
- Two anchors per bracket. It is prohibited to connect more than one anchor clamp to one anchor bracket. The same rule applies to building facades. One clamp is used for one support;
- Incorrect choice of couplings. When laying any cable products, couplings must be available for emergency situations (wire line break);
- Connecting cable products at a support point. SIP cables are connected in the spaces between the supports, and not on them.
Below we describe in detail the rules for storing and transporting SIP-3, as well as popular manufacturers in Russia.
SIP 3 cable fastening
Features and Benefits
SIP-3 is characterized by the absence of a zero core, and it can be installed without additional supporting structures, such as a cable, cable, guy wire. The advantages of the wire include:
- high fire safety;
- the ability to carry out repairs on a working highway;
- no need to use insulator traverses;
- Possibility of installation in city conditions in compliance with safety and construction requirements;
- resistance to tensile stress prevents line breakage as a result of falling branches and other objects;
- expansion of the security zone;
- SIP and bare cable can be mounted on one support;
- the wires do not overlap, which eliminates short circuit;
- product reliability, uninterrupted operation of consumers;
- ease of care and maintenance;
- high speed of repair work;
- reduction of voltage losses on routes;
- excellent performance characteristics of SIP-3 wire;
- reducing costs when installing a new power line;
- mounted on low power transmission line supports;
- You cannot connect to the power line without special permission.
Application
The cable is used when installing overhead power lines. The cable transmits and distributes electrical energy between consumers; the alternating current parameters in the network must correspond to the characteristics of 20 kV (35 kV maximum), 50 Hz. Laying is carried out in areas with temperate, cold and tropical climates in industrial and marine areas (sea coast, shore of a salt lake, areas with saline sand).
The conductor is used when constructing sections of routes, branches and taps in compliance with the rules of voltage distribution. The self-supporting wire SIP-3 can be installed in urban areas, rural areas, and uninhabited areas where it is necessary to lay long-distance mains with minimal voltage losses. Thanks to the possibility of installation on supports installed at a large distance from each other, the cable is laid over historical and architectural monuments. This does not disrupt the overall composition.
The wire is applicable only for connecting the first category of consumers. Due to the possibility of selecting the required cross-section, a reduction in material costs for the construction of additional substations is achieved.
Technical parameters of SIP-3 cable
The wire functions perfectly in any weather and in hazardous environments, and is resistant to mechanical and chemical damage. Basically, the cores are made of durable aluminum wire with stable mechanical parameters along the entire length. Main technical characteristics:
- The wire can heat up to 80 degrees; when overloaded, this temperature reaches 150. Critical indicators at which a short circuit occurs are from 200 degrees;
- The inner insulating layer of the wire is made of fire-resistant, sun-resistant polyethylene;
- Permissible temperature range from -50 to 70 degrees. Thanks to the insulating layer, the cable can be used in fairly aggressive outdoor environments, in industrial areas, tropics, etc.;
High voltage cable
- The insulating shell is resistant to moisture. But in areas with high humidity it is necessary to use sealed protection for the wire;
- Cable laying on supports, their connection and wiring of linear branches to them is carried out using special fittings for SIP products, which ensures the tightness of all boundaries.
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Specifications
Technical characteristics of SIP-3 are presented by the following parameters:
| Rated voltage | 20 kV or 35 kV; |
| Temperature limits to maintain performance | -50 / +50 degrees; |
| duration of service | 45 years; |
| installation at temperature | above -20 degrees; |
| short circuit parameters under which the network continues to operate | temperature 250 degrees, duration 5 seconds; |
| emergency work | maximum 8 hours at 130 degrees; |
| heating the core | 90 degrees; |
| breakdown voltage in the network at 20 kV | 24000 V; |
| Elek. SIP-3 resistance per 1 km | 0.125-1.91 Ohm depending on the cross-section. |
The tests are carried out as follows: the wire is kept in water for 10 minutes, and the temperature of the liquid can range from +10 to +30 degrees. After this, a standard SIP is connected to a network with a voltage of 4 kV, protected at 20 kV - 6 kV, protected at 35 kV - 10 kV and a frequency of 50 Hz.
Purchase
You can buy a wire with the most favorable conditions by contacting our company. We work with trusted manufacturers and do not use the services of intermediaries, which allows us to reduce the cost of cable and wire products to a minimum. Placing an order is done in the fastest and most convenient way - through the website or by email. After receiving your questionnaire, we immediately begin to formulate the terms of purchase.
We work with individuals and legal entities, engaged in wholesale and retail trade. Complete with the product, the customer receives a certificate of conformity and a quality certificate. If necessary, our consultants will answer all your questions. You can buy products from the assortment available in the warehouse or from the manufacturer to order. The price of SIP-3 wire depends on the delivery conditions and order volume. For regular customers, we have provided a system of discounts and special offers.
Spiral matings
Products are manufactured in accordance with technical specifications 3349-033-27560230-33, and their installation is carried out on the basis of standard document 16.K71-272-98. The purpose of the ties is to fasten insulated SIP-3 wires to insulators. They can have different designs and carry out single (for BC-...-01) and double fastening (carried out within one insulator).
The strength of the connection established by the standards makes it possible to eliminate damage to the supports in the event of a cable break or other types of accidents. If the load level exceeds the calculated one, then the conductor slips in the knitting. For single knitting, a strength of 3 kN is provided, for double knitting - 0.5 kN.
The single connection device provides for the expansion of the annular part of the binding and its installation on the neck of the insulator. The branches of the product are wound around the wire, which assumes a lateral position of the latter in relation to the insulator.
The double connection device involves mounting the ring parts of two ties on the insulator neck, the branches are directed in opposite directions and wound onto the cable. The conductor itself passes over the insulator cap.
Manufacturers of SIP-3 brand wire
Currently, more and more cable factories are opening in Russia. Therefore, choosing a suitable manufacturer is quite difficult. Experienced electricians recommend giving preference to companies that have been on the market for at least 10 years and also have positive reviews of their work.
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Also, before purchasing any wire, it is necessary to perform a visual inspection, because even a small crack in the insulating layer can lead to irreversible consequences.
Important! If a person does not understand wires, then it is better for him to seek help from professionals. Below are a number of leading manufacturers on the Russian market.
Kamsky Kabel LLC
The company was founded in 1957. Currently it is a leader not only in Russia, but throughout Europe. The plant has nine workshops with the latest equipment. The entire range presented on the website is always in stock. There are more than 50,000 thousand standard sizes of cable products. The company has fairly low prices compared to those listed below.
Transporting reels
JSC "Rybinskkabel"
Began his work in the 50s of the last century. During this time, the company entered into many large deals with industrial enterprises, including in the nuclear energy sector. Opened many branches throughout Russia. The company has only positive reviews and many awards.
Important! The company delivers products anywhere in the world by air or rail. There are about 30,000 thousand cable sizes available.
LLC "GK "Sevkabel"
Construction of the plant began in 1879. It is one of the oldest in Russia. There are more than 25,000 thousand macro-sized cables in stock. There is a testing center on the territory of the plant. Therefore, before sale, all products are tested. The enterprise was recognized as the most promising in the country. The plant works with countries in Europe and Asia. Products are manufactured using the latest German equipment.
JSC "Moskabel Plant"
The company has been operating for more than 75 years. One of the three largest Russian manufacturers of cable products. Engaged in supplies of products to nuclear power plants. Fulfills orders for wires of any length. We have our own online store with delivery anywhere in Russia. The assortment includes more than 50,000 thousand standard sizes. By the end of 2020, the factory plans to purchase new equipment and begin producing cables with high performance properties.
Manufacturing process
In conclusion, it should be noted that SIP wires are an integral part when installing power lines. To choose a product of higher quality and at an affordable price, you need to read reviews about the factories presented above.
