The operation of electrical networks in the open air makes the installer more demanding, as an aggressive environment can destroy even high-quality insulation in a matter of months. Street wiring It is constantly exposed to ultraviolet light, temperature changes, high humidity and direct precipitation, which makes ordinary twists deadly. If you plan to organize lighting of the site, connect a pump or mount video surveillance, you need to understand that standard methods of connection used indoors are categorically not suitable here.
The main purpose of any connection in the open air is to provide absolute tightness contact, eliminating the ingress of moisture inside the conductors. Water that penetrates the junction site causes electrochemical corrosion, which leads to increased resistance, heating and eventual short circuit. That is why the choice of materials and installation technology becomes a matter not only of comfort, but also of life safety. In this article, we will discuss proven methods that will allow your system to last for many years without failure.
Before you start, it is important to assess the scale of the task and select the appropriate components. Cable products for the street must have markings that allow external gasket, for example, VVGng or specialized armored options. Ignoring this requirement will cause the insulation to crack in the cold or to flow in the sun, leaving bare veins unprotected.
Basic requirements for street connections
Any connection of wires on the street must withstand not only mechanical stress, but also the chemical effects of the environment. Dust, dirt and chemicals that are sprayed on roads in winter can settle on surfaces and create conductive bridges. Therefore sealing This is the first and most important requirement. Even a microscopic crack in the insulation will eventually turn into a hotbed of destruction.
The second critical factor is mechanical strength. Wind, tree swings or accidental grazing should not break contact. ScooperEven carefully executed, in the wind gradually weakens and begins to sparkle. For the street, methods are needed to ensure rigid fixation of the lived relative to each other.
⚠️ Attention! The use of conventional PVC tape for street work is unacceptable. The glue in it dries out in the cold or spreads in the heat, after which the tape simply falls off, leaving the connection open.
The temperature range should also be taken into account. Materials selected for insulation shall remain elastic at -40°C and shall not melt at +60°C. Sharp temperature changes cause thermal expansion and compression of metals, which can lead to a break in the contact if it is made incorrectly. Heat resistance Components are a prerequisite for durability.
Choosing the Right Cable and Tools
The success of the event depends on the right choice. cable. For outdoor use, cables with double insulation and labeled "ng" (non-combustible) or "LS" (low smoke), although the resistance of the shell to UV radiation is more important for the street. Cable VVV In ordinary black insulation often does not withstand a long sun, so it is better to choose specialized brands, such as: KG (flexible cable) with rubber insulation or armored options for underground gasket.
The set of tools should be minimal, but high-quality. You'll need:
- 🔪 A special knife to clean the insulation so as not to damage the veins.
- 🔧 Passengers and bogocreats with isolated handles.
- 🔥 A building hair dryer or gas burner for thermal shrinkage.
- 🧴 Degreaser and clean rags.
Pay special attention to the tools for creating contact. If you plan to use it pressingYou will need the appropriate sleeves and sleeves. For soldering, a powerful soldering iron will be required, since in the wind the heat quickly dissipates, and high-quality warming becomes difficult. A soldering iron It should be designed to work with large cross sections, if we are talking about lines of force.
Always clean the insulation at a small angle, so as not to make incisions on the copper vein itself - this place will become the point of future fracture when bends.
The method of pressure: the most reliable option
Pressurization is considered one of the most reliable ways of connection, especially in conditions of vibration and humidity. The essence of the method is that the cleaned ends of the wires are inserted into a special shell-shellwhich is then pressed with press-cloths. This creates a monolithic connection with excellent electrical conductivity and mechanical strength.
For the street, it is necessary to use tinted copper shells or shells made of non-ferrous metals that are resistant to corrosion. Aluminum wires are connected only by aluminum shells, and copper wires are connected by copper. Mix metals in one sleeve without special pastes is impossible, as the galvanic corrosion will begin. After pressurization, the connection is necessarily sealed.
The process is as follows:
- Clean the insulation for a length equal to half the length of the sleeve on each side.
- Then, put the rods in the back and put them in the back.
- Perform a clench with ticks in two or three places.
- Put on a heat shrink tube with a glue layer and warm up.
⚠️ Attention! Do not use conventional pliers for pressing power cables - they will not create enough pressure, and the contact will warm up. It's professional ticks that are needed.
It is important to find the right size of the sleeve. If it is too large, it will not work out to squeeze it qualitatively, and there will be a void inside where moisture can condense. If it is too small, you will damage the veins when inserted. Landing density It's a key success parameter.
Salting and welding: classic methods
Salting provides excellent electrical contact by creating an alloy of solder and copper. However, on the street, this method requires careful protection. The solder itself does not rust, but the fluxes used in soldering can be hygroscopic and eventually break the compound if not removed completely. For the street, it is better to use acid-free fluxes or soldering paste.
Welding wires is an even more reliable, but time-consuming method. It turns the twist into a monolithic drop of metal. It is ideal for mechanical strength, but requires skill and equipment. The main advantage is the absence of third metals (as in solder), which excludes galvanic pairs. However, shrinkage The welded joint is more difficult due to the uneven surface of the drop.
Comparison of methods of protection of soldered joints:
| Protection method | Outside service | Difficulty of installation | Reliability |
|---|---|---|---|
| Glue-filled shrinkage | 15-20 years | Low. | Tall. |
| Silicone sealant | 5-7 years | Medium | Medium |
| Epoxy resin | 10-15 years | Tall. | Tall. |
| Insulation + lacquer | 1-2 years | Low. | Low. |
After soldering or welding, the connection site should be immediately isolated. As long as the metal is hot, the risk of oxidation is maximum. Canifol or the residues of flux is better to wash off with alcohol before the final sealing to exclude a chemical reaction under the layer of insulation.
☑️ Pre-sealing check
Use of couplings and boxes
The most civilized and professional approach is the use of ready-made cable-clutch And the connecting boxes. These products are designed specifically for use in harsh environments. They have an IP68 protection rating, which means they are completely leakproof even when fully submerged in water.
There are filler clutches, inside which there is a two-component polymer. When connecting the wires and closing the body of the components, a reaction occurs, and the entire inner cavity turns into a monolithic block of plastic. This completely eliminates the access of oxygen and moisture. Also popular. heat-restricted couplings It's got built-in shell casings and adhesive.
Advantages of using specialized boxes:
- 🛡️ Full protection from mechanical damage (stones, shovel).
- 💧 Water resistance guarantee of IP68 class.
- 🔌 Quick access for audit (if the box is not filled).
- 🌡️ Stability of parameters over a wide range of temperatures.
What is a two-component filler?
It is a system consisting of two substances that are mixed immediately before use. After mixing, an irreversible chemical reaction begins, turning the liquid into a solid dielectric. This is the best way to protect the connection from water forever.
When installing the box, it is important to enter the cable correctly. Use glands or sealants that tightly clamps the cable in diameter. A simple hole in the box’s case is an open door for moisture that will flow inwards along the walls of the cable.
Typical errors and security measures
The most common mistake is saving on materials. Trying to connect a street cable with a twist and wrap three layers of insulation will lead to problems in the first winter. Oxidation Copper happens quickly, and after a year you may find blackened, crumbling wires.
Another mistake is leaving the ends of the cable just lying on the ground or grass. Even if the connection is sealed, the cable itself can draw moisture from the soil through microcracks. Lift connections above the ground or use special racks. Grounding Metal parts of street lighting also have to be done by the rules, not just "stuck in the ground."
⚠️ Attention! Never do work under stress, even if it rains and it seems like “nothing will happen.” Wet clothes and ground under your feet make you an excellent conductor of current.
Don’t forget about visual control. Regularly, at least once a season, check the condition of street connections. If the thermal shrinkage has become cloudy or cracks appear on the box - this is a signal for immediate replacement. Prevention It's always cheaper than emergency repairs.
Using ready-made sealed clutches with adhesive layer saves time and guarantees a result that cannot be achieved by artisanal insulation methods.
Frequently Asked Questions (FAQ)
Can I use a regular blue tape for street wiring?
Absolutely not. Conventional PVC insulation has no UV protection, cracks in the cold and peels off from moisture. For the street, only specialized tapes with a butyl rubber base or, better, shrink tubes are suitable.
How to connect copper and aluminum wire on the street?
The direct connection of copper and aluminum is prohibited due to electrochemical corrosion. Use special transient sleeves or terminals with quartz vaseline paste, which prevents oxygen from entering. Make sure to seal the joint.
Do I need to ground the street outlet?
Yes, any outlet must be grounded and connected via an RCD (protective shutdown device) with a leakage current of no more than 30 mA. This will save lives in case of insulation failure in wet weather.
Which cable is best for laying in the ground?
The best choice is an armored cable WBBS. It has steel band armor, protecting against rodents and mechanical damage, and does not require additional pipe when laid in the ground.