In any case, electrical work is carried out with the connection of wires and cables. At the same time, the same type of flexible conductors are not always found. Any master can cope with such work, there would be a desire, time and necessity. At the same time, not everyone knows how to connect a stranded wire to a single-core one.
Methods for connecting dissimilar wires
In order to ensure the correct connection of wires, and dissimilar ones (with one, two cores), there are dozens of methods.
These methods can be roughly divided into two main categories:
- The first includes those techniques, the implementation of which requires specific equipment or skills.
- Second - those where almost any home master can prove himself, since special skills are not needed here.
Each of the ways hasits advantages and disadvantages. Let's start with ways to connect stranded and solid copper wire (or aluminum), where additional elements in the form of terminals are not needed, which significantly reduces the cost of the process.
Twist
Although this method is highly discouraged by the requirements of the PUE, many home craftsmen continue to use it. And if everything is done correctly and with a responsible approach to work, the result will be reliable and durable for electrical networks with an average current load.
Using parallel stranding, a solid wire can be easily connected to a multi-core cable. At the same time, the monolithic core is additionally bent, which gives more rigidity than twisting two identical wires with several cores. Moreover, this method is relevant for wiring not only from copper, but also from aluminum.
Those craftsmen who want to know how to properly connect a stranded wire to a single-core one should understand that this method is not suitable for dissimilar metals! This is due to the fact that the connection can only last a short time, because metals of different nature are a galvanic couple. And under the influence of current, it begins to collapse, and quite quickly.
Splice wires
This type of connection is an improved version of twisted wires. And at the same time, the quality is much higher than in the absence of solder. In addition, covering copper wire (it is currently used much more often than aluminum)molten lead-tin mass (tinning procedure), it is possible to provide reliable protection against oxidation due to high humidity.
The solder itself, based on its composition and melting point, can be of several types:
- PIC 15 (280o);
- PIC 25 (206o);
- PIC 33 (247o);
- PIC 40 (235o);
- PIC 60 (191o);
- PIC 61 (183o);
- PIC 90 (220o).
With this method of mounting a stranded wire with a single-core wire, for a high-quality connection, all cores must be tinned with rosin (flux) and the solder itself.
Tinning and soldering technique
The procedure is as follows:
- Conductors must be stripped of insulation (small area) and of traces of oxidation (if present).
- After the soldering iron is up to operating temperature, they should heat up the rosin. And after melting it, dip the wire.
- Next, put some solder on the end of the soldering iron tip.
- Now, making smooth movements along the line of the core, the solder is transferred to it.
After the tinning procedure, the wires can be connected with a twist, which was described above. Only before pulling them off, it is necessary to remove the evaporated flux residues from the surface. And since the wires are now stiffer, you should use pliers to secure the twist.
How betterconnect solid and stranded wires? Now it remains to heat the junction until the solder melts. You can add a little more if needed. Copper is a good conductor of heat, therefore, due to the strong heating of the conductive cores, the insulation may melt. For this reason, it is worth choosing a solder with an optimal melting point. It is also worth reducing the duration of exposure to the soldering iron.
Swaging method
With this method of connecting wires, additional equipment will be required, since it is carried out by crimping with sleeves. They can be made of copper or aluminum, depending on the material of the conductors themselves. The main thing with this installation of a stranded wire with a single-core wire is to choose the right size. In each case, this is done taking into account the diameter and number of cores.
The conductive ends should fill almost the entire space of the sleeve, but at the same time there should be some free space. For this reason, it is necessary to select the correct sleeve dimensions here, since the quality of the crimp depends on this factor.
Actually, this is the main difficulty of this method of connecting wires - the sleeve should not be too big or small. The procedure itself is as follows:
- First, strip the ends of the wires from the insulation (the length of the section should slightly exceed the dimensions of the sleeve).
- Each core should be stripped to bare metal. Oxides can be removed with sandpaperfine grit.
- Next, the wires are twisted in the way we already know.
- At the end of the process, the sleeve is crimped with special tongs.
Connecting a stranded wire to a single-core wire is not difficult. Difficulties arise only at the stage of selection of shells and the presence of ticks. Of course, for this purpose, you can use pliers or pliers. However, no one can give any guarantees regarding the reliability of such a connection.
Use terminal blocks
The wire connections listed above in any case have certain disadvantages. And twisting is generally prohibited by the rules for the installation of electrical installations (PUE), although this method is still in use to this day. They are unreliable, short-lived, and in addition, some methods require a special electrical tool or appropriate professional skills.
Not every home craftsman has soldering skills to connect stranded wires to solid wires. Although the procedure does not seem so complicated. Besides, how to execute it when the object is de-energized? Even greater problems arise when it is necessary to deal with wires made of different metals. It is impossible to connect them with a twist.
However, despite these difficulties, there is a sure way out, which is to use different terminal blocks. There are a great many of them today, and they are designed for almost any situation. What can shops offer?
Types of pads
By and large, it is the terminal elements that provide high quality wire connections. And this is not only a guarantee of their reliable fixation, the electrical contact itself is quite strong. The conductive surface of the terminal blocks is usually made using brass or any other material that is not able to interact with either copper or aluminum.
You can easily connect a stranded wire to a single-core wire using such elements. Moreover, they can even be heterogeneous in nature.
From the whole variety of terminal blocks, two main groups can be distinguished:
- Clamping elements. The core is fixed with a built-in spring.
- Screw structures. The wire is clamped directly by the screw.
Regarding the use of screw terminal blocks, keep in mind that both aluminum and copper are fairly soft materials.
Therefore, excessive tightening can result not only in stripping the thread, but also in squeezing the conductive wires. It is also impossible to exclude the possibility of their breakage.
Knife and pin connection
In fact, this is a plug-in type of connection, which is very simple to implement. A kind of socket or socket is attached to the end of one of the wires (by crimping or soldering), and a pin or plug is attached to the other. The connection is made as easy as shelling pears: the plug is inserted into the socket.
At the same time, this method of connecting a stranded wire to a single-core wire has more disadvantages thanmerit:
- neither pins nor sockets are designed for high current;
- design often exposed;
- in terms of time, the process takes not so little (crimping or soldering), and besides, it is quite laborious.
As for the merits, it is perhaps only one - the ease of connecting and disconnecting the chain. In this regard, this technique is relevant only in cases of equipment installation, rather than for electrical wiring.
Features of the insulation of electrical connections
It is important not only to ensure a strong and reliable connection of wires, it is also necessary to take care of the high-quality insulation of their bare parts. This will prevent accidental contact of conductive elements with the human body or between themselves. Neither ends well.
Thinking about how to connect a stranded wire to a single-core, it is worth taking the time to choose the insulation material. In many ways, it will depend on the operating conditions of the electrical contact. In most cases, it is enough to stop with heat shrink or vinyl tubing, including the use of special electrical tape.
When exposed to high temperatures, use varnished cloth and fabric insulating tape to close the connection. This insulation is able to withstand up to 100 °C for a long period of time.
