Connection of electrical wires by twisting remains one of the most common, despite strict rules of PUE, which in its pure form this method is not welcome. Many electricians with many years of experience still consider twisting the basis of high-quality contact, if it is performed correctly and supplemented by soldering or welding. However, for a beginner, this procedure may seem simple only at first glance, hiding many nuances, ignoring which leads to heating, oxidation and even fire.
In this article, we will discuss in detail how to use a wire twister so that the connection serves for decades without complaints. You will learn about the right twisting techniques, the necessary tools, and the critical mistakes that most home craftsmen make. Understanding the physical processes that occur at the contact point will help you avoid situations where the wiring fails a month after the repair.
Before you start working, it is important to understand that twist It is not just the interweaving of the veins, but the creation of a dense mechanical and electrical contact. The quality of this contact directly depends on the compression force, the area of contact and the absence of an oxide film between the metals. Next, we’ll look at a step-by-step action algorithm that will allow you to perform a professional-level connection.
Tool preparation and insulation cleaning
Quality slinging is impossible without the right tool. You will need bokosnips, passages, a stripper to remove insulation and, preferably, special mites for twisting. Using a knife to clean wires is permissible, but requires extreme caution so as not to damage the metal vein itself. Incisions on copper or aluminum become places of concentration of voltage and can lead to a fracture of the wire under load.
The length of the cleaned area depends on the diameter of the wire and the number of wires connected. For standard household wires with a cross section of 1.5-2.5 mm2, the stripping length of 3-5 cm is considered optimal. If you clean too little, the twist will be short and unreliable; if too much, the consumption of insulating materials will increase and the risk of short circuit when mounting in a box will increase.
Particular attention should be paid to the condition of the living. If you are working with old wiring, the metal may be dull or oxidized. In this case, it is necessary to clean the veins to a characteristic metallic shine. For aluminum wires, this is critical, as the aluminum oxide film has high resistance and prevents normal conduction.
⚠️ Warning: Never use the teeth of the passages or the bogo cutters to clean the wires unless they are designed for this function. Snacking part of the cross-section of the vein reduces its throughput and creates a point of local overheating.
Use a stripper with adjustable clamping diameter – this ensures that the insulation is removed smoothly, without damaging the metal, which is especially important for soft multicore wires.
Techniques of performing twisting for different types of wires
The method of twisting directly depends on the type of wires connected: single-core (monolithic) or multicore. For single-core wires, the most effective method of parallel twisting with subsequent banding or the method of sequential crossing. In the first case, the cleaned ends are applied parallel to each other and twisted with passages, providing a large contact area.
Multi-core wires require a more delicate approach. They can not be twisted as hard as the monolith, otherwise the thin hairs can be damaged. The best option is the connection by the method of "weaving" or the use of branch compressions. However, if you decide to do it is twisting, the veins need to be fluffed, folded and tightly twisted, avoiding excessive mechanical stress.
The number of wires that are simultaneously twisted also matters. Norms and common sense dictate a limit of 2-4 wires by section to 2.5 mm2. Trying to twist five or more wires into a single beam is a guarantee of poor contact and difficulty with subsequent isolation. If you need to connect more veins, it is better to use a switchboard with terminals or make several separate twists.
Step-by-step instructions for creating a reliable connection
The process of creating a high-quality twist requires consistent execution of operations. Violation of the procedure can lead to weakening of the contact already at the installation stage. Below is an algorithm that will ensure maximum reliability of the connection.
☑️ Checklist of the right twist
Start by folding the cleaned ends of the cross-cross wires in the middle of the cleared area. Clutch the intersection with the passages and start rotating the tool, twisting the wires around each other. Movements must be confident but controlled so as not to break the vein. The twisting is done clockwise when looking at the end of the connection.
After the formation of the main twist, it is necessary to seal the turns. Take the second passages or use the first sponges, clamping the twist closer to the isolation and with effort turn the turns to lay as tightly as possible. The ends of the twist, if they protrude unevenly or have sharp edges, it is better to trim with bokokornikov, leaving a reserve of several millimeters.
The final stage of the mechanical part is to check the strength. Try to slightly pull the wires in different directions - a quality twist should not disintegrate or slide. If the connection is held tight, you can move to isolation and additional processing.
There are several main types of twists, each of which has its own application features:
- 🔹 Parallel twisting - used to connect wires of one section, provides good contact, but requires brace.
- 🔹 Consecutive twisting - is used less often, wires wrap each other, the method is good for temporary connections.
- 🔹 A bandaged violin - the main method for power lines, where an additional wire for compression is superimposed over the twisted veins.
- 🔹 Responsive twist - allows you to connect an additional wire to the main highway without breaking it.
⚠️ Attention: When copper and aluminum wires are twisted, an electrochemical reaction directly occurs, leading to rapid destruction of the contact. Use intermediate materials or terminals!
Comparative table of connection methods
To better understand the differences between methods, it is worth considering their characteristics in comparison. This will help you choose the best way for specific installation conditions.
| Parameter | Simple twist. | Rational scum | Welded violin | Screw terminals |
|---|---|---|---|---|
| Reliability of contact | Medium | Tall. | Very high. | Tall. |
| Difficulty of implementation | Low. | Medium | Tall. | Low. |
| Equipment required | Passenger | Sleeve iron, sell it. | Welding machine | Screwdriver. |
| Compliance with PUE | Not recommended | Permitted. | Permitted. | Permitted. |
As you can see from the table, simple twisting is inferior to combined methods. That is why professionals rarely leave the twist “as is”. Adding soldering or welding turns the mechanical connection into a monolithic conductor, eliminating gaps between the veins where oxidation can occur.
Insulation and sealing of compounds
A well-performed squirrel is only half the case. The second, no less important part is the quality of insulation. It protects against electric shock and prevents moisture and dust from entering. The most common materials are PVC insulation and shrink tube (UTT).
When using the insulation, start winding it at least 2-3 cm from the edge of the twist, moving to another wire, and return back. There should be at least two layers, and the second layer should overlap the joints of the first. It is important to stretch the tape during the winding process, so that it tightly fits the relief of the twist.
The shrink tube provides better tightness. Pick up a tube of the right diameter, put it on the wire until twisted, make a connection, move the tube to place and warm up with a building hair dryer or lighter. The tube cannot be heated with an open flame for too long - it can burn or melt unevenly.
Nuances of the use of heat shrinkage
If the twist is long and the tube is short, you can use two tubes in a span. The main thing is that the heating was uniform throughout the length, otherwise there will be voids with air inside.
Common mistakes and safety practices
Errors in the twisting of wires are often fatal for wiring. The most coarse of them is the twisting of wires of different cross-sections or of different metals without adapters. A thin wire when connected with a powerful load will overheat, even if the thick conductor has not even warmed up yet.
Another common mistake is the insufficient length of the twist. Five turns for thick wire is nothing. Contact will be weak, resistance high, which will lead to heat. It is also dangerous to leave the sharp ends of the lived sticking out of the insulation; they can pierce a layer of insulation or cause a breakdown.
- 🚫 The energized violin - strictly prohibited, the risk of shock 100%.
- 🚫 Aluminum and copper compound - leads to galvanic corrosion and fire.
- 🚫 Scotch insulation Stationery tape is not a dielectric and melts when heated.
Always check for no voltage before starting work with an indicator screwdriver or multimeter. Even if you are sure that the machine is turned off, rechecking will never be superfluous. Safety is more important than minutes saved.
⚠️ If the twist is made in the wall (which is unacceptable by modern standards, but is found in the old fund), it should be perfectly soldered and isolated, otherwise access to it for repair will be impossible without destroying the finish.
The golden rule of the electrician: twisting is only a rough version of the connection. For long-term and safe operation, it must be soldered, welded or replaced with a certified terminal.
FAQ: Frequently Asked Questions
Can I roll more than 4 wires together?
Technically, you can twist more, but the quality of such a connection will be low. The more wires, the more difficult it is to ensure uniform compression of all the veins. It is recommended to do several separate twists or use distribution terminal pads.
What is better to isolate the twist: tape or tube?
The shrink tube is preferable, as it creates a sealed monolithic coating, not prone to slipping. The insulation can eventually dry or unwind, especially in conditions of temperature changes.
Does the PUE allow for a simple twist?
According to the PUE (P. 2.1.21), the connection, branching and ending of wires shall be carried out by pressing, welding, soldering or compression. Simple twisting in the list of permitted methods is not listed, although it is widely used as a step before soldering.
What to do if you need to combine copper and aluminum?
Straight twisting is forbidden. Use special terminals (such as WAGO with pasta), a bolt connection through a washer or a branching compress ("nut"). This will prevent electrochemical corrosion.