The organization of a home energy network is a very complex and responsible process. Most home masters prefer to use a SIP cable, a self-supporting insulated wire, which is designed to transmit and distribute electricity up to 35 kW to solve this problem.
At the same time, one of the main tasks facing the organization of the power grid is the branching of power lines. For these purposes, electrical experts recommend the use of branch clamps. They guarantee a reliable and tight connection and are easy to handle.
Wires and Taps
The electric network, conditionally, includes two elements - trunk and branch cables. The first go directly from the source, act as the main transmitters of electricity. Branch wires are connected to the mains and bring electricity to a consumer located far from the center line.
Routed power lines should be not only durable, but also safe. Already at the installation stage, it is important to create conditions that allow at any time without risk to health to replace any component of the chain, to connect SIP cables. Branch clamps are intended for this purpose.
Such electrical fittings are a fiberglass reinforced plastic box in which there are two inputs. Toothed clamps are located inside the housing, which when tightening the fixing bolt pierces the cables and acts as a jumper.
Requirements
For reliable and durable connection of SIP cables, it is necessary that the connection clamps meet certain requirements. Their body should be made of fiberglass reinforced plastic - for better insulation of parts.
The plastic used for the manufacture of reinforcement must be strong, resistant to mechanical stress. In addition, the branch clamp must be immune to sunlight, ultraviolet rays and thermal radiation.
After connecting the wires, the valve body must be perfectly sealed to prevent moisture from entering the jumper. Oxidation of contacts can result in a blackout of the network or, even worse, a short circuit.
Types of Clips
On the market you can find various models of electrical fittings presented. All devices are divided into two large groups:
- Branch clamps with simultaneous tightening of the bolt, when both the trunk cable and the branch are tightened with one screw.
- Armature with separate piercing wires.
The use of elements of one or another group depends on the required reliability of the connection. We must not forget that there are different models of clamps that have their own characteristics. For example, some of them can be dismantled, while others cannot.
Branch clamp operation principle
Using electrical fittings, you can be sure that you can connect SIP cables without removing the insulating layer. This increases the reliability of the connection and the security of the connection, and also speeds up and simplifies the installation process.
Before carrying out all operations, turn off the power to your home. The connection process itself consists of several steps:
- Install the trunk wire in one of the holes of the piercing clamp.
- Pull the outgoing cable through the second hole in the valve.
- Tighten the upper tightening bolt until the thread on its head breaks.
- For reliability, fasten the branch clamp to the supporting surface.
If you use clamps with separately securing the trunk and outgoing wires, each cable is punctured immediately after being pulled through the hole. Be sure to insulate the free ends of the wires with plastic caps on them.
Tightening clamps
Branch SIP-fittings with simultaneous tightening of bolts are designed to create bends from the main lines with aluminum or copper wires. They provide reliable and tight contact by a piercing method. Depending on the destination, several types of reinforcement are distinguished.
The first of these is branch clamps designed to connect street lighting and drain from the mains of the input wires to the house (P616). Used to connect cables of small cross-section (1.5-2.5 mm 2 ) and vein trunk wires (cross-section of conductors from 5 to 150 mm 2 ).
The second type is designed directly for branching from the input line into the house. Such a branch clamp (645-P) is used to connect the central wires with a cross-sectional area of 6 to 150 mm
2 with core branch cables of a cross-sectional area of 4 to 35 mm
2 .
Features of clamps with simultaneous tightening
A key feature of electrical fittings is the ability to dismantle them, but their reuse is not allowed. This is due to the fact that the thread of the head of the tightening bolt breaks at the time of installation. The tightening bolt is most often made of soft aluminum alloy.
Another feature of the devices is the fact that installation is possible even on a non-powered line. The insulation of the clamps must be made of heat-resistant polymer material. Its tests are carried out by immersion in a tank with water and passing through it an electric current of 6 kW for 60 seconds.
Valve with separate tightening bolt
In valves with a separate tightening, a piercing clamp secures the trunk wire and the branch with individual bolts. Similar devices are used to create several branches from one point. The main representatives of this model range are clamps of the type P617, P14 and p619.
All models of fittings are used to connect aluminum and copper insulated branches. The wires are also tightened with a soft aluminum alloy bolt with a torn head thread.
The branch insulated clamp P617 provides contact between the trunk and the branch in various ways. For connecting the center line there is a clamping gear plate, and for the branch connection is provided with preliminary removal of insulation. In type P619, both cables are connected by clamping jumpers.
Other types of clamps
It is almost impossible to give a full description of clamps of all kinds and types - too much variety. A device that deserves special attention is the RS 481. It is designed to connect electrical measuring instruments, short-circuit and protective grounding of highways, mounted at the beginning and at the end of the line for the entire service life.
Another notable type of SIP-fittings is a clamp with simultaneous tightening type P70. It is used for branching trunk power lines with a cross section of conductors from 25 to 150 mm 2 . The devices are designed for operation at temperatures up to –60 ° .
It is necessary to use a branch clamp when carrying out a high-voltage line, connecting street lighting and for entering an electric cable into the house. Their use improves the safety of installation and the durability of the created power grid.