Many, probably, have come across such a problem when a twist of wires begins to spoke and knock out machine guns. Naturally, it is unpleasant and presents a greater threat to security. Using the wires from the home power grid different materials It is necessary to clearly know how to connect the copper and aluminum wire and make it right. After all, with direct contact, copper and aluminum are oxidized, disrupting the quality and integrity of the twist.
Any conductor (copper, aluminum, steel and others) has a certain electrochemical potential. In the interaction of moisture, which is available in the air and oxygen, electrochemical corrosion occurs in the generated electroplated element. This reaction leads to a deterioration in the electrical conductivity of the wire. In this case, it is necessary to take additional measures to protect compounds.
The table below defines the potentials of various conductors. Knowing them, you can correctly pick up materials well connected with each other.
| Metal | Copper, her alloys | Tin Solder | Aluminum | Duralumin | Steel | Stainless steel | Zinc coating | Chrome coating | Silver | Carbon (Graphite) | Gold Platinum |
| Copper, her alloys | 0,00 | 0,25 | 0,65 | 0,35 | 0,45 | 0,10 | 0,85 | 0,20 | 0,25 | 0,35 | 0,40 |
| Lead-Ol. solder | 0,25 | 0,00 | 0,40 | 0,10 | 0,20 | 0,15 | 0,60 | 0,05 | 0,50 | 0,60 | 0,65 |
| Aluminum | 0,65 | 0,40 | 0,00 | 0,30 | 0,20 | 0,55 | 0,20 | 0,45 | 0,90 | 1,00 | 1,05 |
| Duralumin | 0,35 | 0,10 | 0,30 | 0,00 | 0,10 | 0,25 | 0,50 | 0,15 | 0,60 | 0,70 | 0,75 |
| Soft steel | 0,45 | 0,20 | 0,20 | 0,10 | 0,00 | 0,35 | 0,40 | 0,25 | 0,70 | 0,80 | 0,85 |
| Stainless steel | 0,10 | 0,15 | 0,55 | 0,25 | 0,35 | 0,00 | 0,75 | 0,10 | 0,35 | 0,45 | 0,50 |
| Zinc coating | 0,85 | 0,60 | 0,20 | 0,50 | 0,40 | 0,75 | 0,00 | 0,65 | 1,10 | 1,20 | 1,25 |
| Chrome coating | 0,20 | 0,05 | 0,45 | 0,15 | 0,25 | 0,10 | 0,65 | 0,00 | 0,45 | 0,55 | 0,60 |
| Silver | 0,25 | 0,50 | 0,90 | 0,60 | 0,70 | 0,35 | 1,10 | 0,45 | 0,00 | 0,10 | 0,15 |
| Carbon (Graphite) | 0,35 | 0,60 | 1,00 | 0,70 | 0,80 | 0,45 | 1,20 | 0,55 | 0,10 | 0,00 | 0,05 |
| Gold Platinum | 0,40 | 0,65 | 1,05 | 0,75 | 0,85 | 0,50 | 1,25 | 0,60 | 0,15 | 0,05 | 0,00 |
According to the requirements of the standards, a mechanical connection between materials is allowed, the electrochemical potential (voltage) between which does not exceed 0.6 mV. Therefore, the direct compound of copper and aluminum is unacceptable - the electromechanical potential in this case is 0.65 mV, which is more than the maximum rate of 0.05 mV. Therefore, it is necessary to choose a kind of gasket between these materials, which optimizes the voltage in the bundle.
Considering the copper wire optimal option The compounds for it will be copper and steel (potential 0.1 mV). Similarly, with aluminum. Accordingly, to connect the copper and aluminum wire correctly, you need to add a gasket (washer) from the steels. Also, you can pick up other combinations of compounds from the table.
Having understood with the electrochemical corrosion of the connected metals, we turn to the consideration of the main methods of connecting electrical wires.
A twist is the most common but less reliable way of connecting wires.
Many resort to this method due to the simplicity and lack of relevant qualifications. But you need to know that when the ambient temperature fluctuations, due to the linear expansion of metals, the following occurs:
Having the goal of obtaining more reliable contact, the use of a twist is better to refuse. But, if you still stop at this connection method, you should follow the following rules:
The number of turns in the twist must be at least three (for thick veins) and at least five for thin (with a diameter of less than 1 mm).
The following acceptable type of connection is a threaded with screws and nuts. It is the most reliable and capable of providing good contact throughout the service life of the wiring.
Limited to long thread, you can easily connect and disassemble any number of conductors:
Use intermediate (spring) steel washers to avoid direct contact of wires from copper and aluminum.
Consider the steps of creating a threaded connection:
To prevent overpressing wires before the first washer, you need to install a spring washer. When, during screwing the nut, it will straighten, the connection will be optimally fixed.
The connection of the wires using the terminal block of reliability is inferior to the connection with the screw and the nut and has perhaps the only advantage:
To create a ligament of conductors in this method, the ends of the veins are cleaned of insulation for a length of 4 - 8 mm (depending on the diameter), are inserted into the hole and clamped with equipped screws.
As an additional precautionary measure, the connection made by the terminal block is recommended to additionally wrap the insulating tape. This is due to the fact that the weakened contact can lead to a random release of veins under voltage.
Connection using Wago Terminals
The most common type of this connection is terminal blocks With spring clamps of the German manufacturer WAGO (Vago). They are intended to connect any species of single-core wires (tinned stranded) cross section from 1.5 to 2.5 mm².
Allocate the main types of Terminals:
The use of these connectors is justified:
As with the methods discussed above, the use of spring terminals Vago is justified when the copper and aluminum wires. To do this, it is enough to remove with an insulation by 8 - 10 mm from the conductor. And insert it into the terminal.
Having studied the question of how to connect the copper and aluminum wire, you can apply the knowledge gained in practice is not doubting the reliability of the connection. You just need to choose one of the methods considered.
poweredhouse.ru.
Hello dear readers of the site sesaga.ru. I wrote this small post with the assistance of my neighbor, Vladimir Sh, for which he was special thanks.
The other day, Vladimir addressed me with a request to see his outlet. A year after repair from the outlet, it began to smell, and over time she also began to warm up. Well, when the socket spawned, he began to beat the alarm.
Everything turned out to be simple. The wiring around the apartment is made by an aluminum wire, and the newly introduced and additional conducted with a copper wire, and copper connected with aluminum by the usual twist without any adapters and fixtures.
Never connect together aluminum and copper. The fire is not excluded.
It was necessary to separate copper from aluminum, but at the same time leave the connection. At hand, nothing suitable was, and the first thing that occurred to the head is to make a bolted connection: cheap and angry.
First of all, we break the connection, and if there is an opportunity, then we bite the damaged parts of copper and aluminum. But, in our case, the wires were short, and we only cut off the most damaged parts, and the rest was cleaned.
To restore the connection, and at the same time separate copper from aluminum we need:
1
. Two bolts with a diameter of 4 or 5mm;
2
. Four nuts with a diameter of 4 or 5mm;
3
. Eight piles of suitable internal diameter;
4
. Insulating tape;
5
. Copper twin wire with a cross section of 2.5 square and about 40 cm.
Remove isolation from aluminum wire and make a semiring of such a diameter to enter the bolt.
I wear the puck on the bolt, and together with the washer insert into the semiring of the aluminum wire.
From above half rings Close the washer and oK Clear nut.
Now the aluminum wire must be increasing with a piece of copper to further connect copper with copper.
We take a segment of a copper wire with a length of 15 - 20 cm, we make a semiring, put on the same bolt, and between two washers oK Clear nut.
You will have this "sandwich".
Now this "sandwich" is insulated and hiding in the depths of the box.
In the same way, we make the second bolted compound.
And now to the resulting two ends, you can freely fasten any copper.
Back restore the scheme.
Molded twists can be irradiated, and you can not fly away.
Next, the twists are insulating, we remove the box inward and wept so that they do not interfere with the outlet.
Well, it remains to connect and fasten the outlet on the wall.
This is so simple, but at the same time in an effective way we connected copper with aluminum, and at the same time, eliminated a malfunction that could lead to unknown consequences.
Good luck!
sesaga.ru.
Until now, there is a considerable number of rooms where electrical wiring is made of aluminum. At the same time, modern systems are based on the use of copper as a conductor. That is why the problem of docking wires from these heterogeneous materials is relevant. About how to docile wires from copper and aluminum will be discussed below.
Often you can meet the statements that copper and aluminum are unwanted to connect to one whole. From the point of view of compatibility, materials are fair assertions. What about the connection of copper and galvanized or steel and silver? There are many options for metal pairs, and remember which of them are compatible with each other, and which are not, difficult. To simplify the task, there are special tables, one of which is presented below.
Table of electrochemical potentials (MV) arising between the connected conductors.
To understand the issue you need to know which processes occur when different electricity conductors are touched. If no humidity is missing, contacts in any case will be reliable. However, in practice, this situation is impossible, since there is always a moisture in the atmosphere, which violates the compounds.
Each conductor of electricity is inherent in some electrochemical potential. This circumstance is applied by a person for practical purposes, for example, batteries and batteries are operating on the basis of different potentials.
When moisture comes into contacting metal surfaces, a short-circuit galvanic medium occurs, the deformation of one of the electrodes occurs. Similarly, one of two metals is also destroyed. Thus, to determine the compatibility of metals, you need to have information about the electrochemical potential of all the materials involved in the reaction.
What will happen if copper is connected directly with aluminum
For technical regulations, a mechanical docking of metals is allowed if the electrochemical voltage between two materials is not higher than 0.6 mV. For example, from the table above, it can be established that in the case of a compound of aluminum and copper, the electrochemical potential is 0.65 mV, which is significantly higher than when docking the same copper with duralumin (0.20 mV).
And, nevertheless, if it is very necessary, you can also connect such not quite compatible materials, which are copper and aluminum. About how to connect copper and aluminum wires, will be discussed below.
Several ways of connecting aluminum and copper wires are used. Moreover, in each of the cases described, special devices will need. Consider each type of docking separately.
This type of compound is the most common, since it is characterized by simplicity and low cost. If you do everything correctly, a wired connection with nuts and bolts will provide reliable contact for the entire service life of the wiring and electrical devices. In addition, you can always disassemble the connection, attach additional conductors, etc. Due to the threaded compound, the relevance of the electrochemical incompatibility of metals is increasing, it is possible to docile aluminum and copper, thick and thin wires, stranded and single-core. It is important to avoid direct contact between heterogeneous materials, making gaskets from spring washers.
To perform work, you will need a bolt and nut, as well as the washer (it should be made of anodized steel).
The connection is performed as follows:
Note! If the dock is carried out for the room in a room where the specifications there are vibration, an additional nut will need an additional nut.
There are several options for terminal connections. One option is the so-called "nuts". Such an unusual name of the terminal workers is due to their external resemblance to nuts. Several varieties of terminals are produced.
The model most primitive on its device has in three distinctive plates. Conductors are located between the plates. Thus, it is possible to avoid direct contacts between heterogeneous materials. At the same time, the "nuts" allow you to maintain the supply circuit of the electrocups.
To achieve the integrity of the contour, it is necessary to clean the supply conductor from the insulating layer, unscrew the pair of bolts, install the bare wire between the plates and turn the bolts again. With the revelation ends, it is necessary to remove the insulator, and then send the wires into the holes located perpendicular to the supply channel. Further, the conductors are fixed between other distinctive plates.
There is a more complex model on the market, the design of which is arranged in such a way that there is no need in the cutting of conductors. The fact is that the plates of the device contains the teeth, which, when squeezing with their bolts, simply tear the insulating layer. The described docking option is considered very reliable.
There is another variant of the terminal shots - ordinary pads. The device is a bar with terminals. To connect two heterogeneous materials, it is necessary to clean their ends and send the wires into the terminals. The ends are fixed by bolts that are on top of the terminal holes.
The connection of copper and aluminum wires can be carried out using WAGO terminal pads. This device refers to the aforementioned terminals, however, the WAGO pads should be told a little more in view of their popularity among buyers.
WAGO is performed in two versions: disposable with a non-removable wire and reusable - with a lever that makes it possible to repeatedly install and remove the conductor.
WAGO is used for all types of single-core wires, the cross section of which is between 1.5 and 2.5 square millimeters. The block can be used in the distribution dump trucks with a current of up to 24 amps. However, in practice it is believed that 10 amps more than quite and large indicators will lead to overheating.
To connect the conductors, it is necessary to send one of them with an effort, with the result that it will securely secure there. To remove the conductor from the hole, also need to make an effort. It should be borne in mind that as a result of the removal of the wire from a disposable terminal bar, the contact may be deformed, so the next time reliable contact is not guaranteed.
It is much more convenient to use a reusable WAGO device. Characteristic feature Such a terminal bar is the presence of an orange lever. With this device, you can dock or disconnect all types of wires with a cross section from 0.08 to 4 square millimeters. Permissible current level - 34 amps.
To create a connection, it is necessary to remove isolation from the wire to 8-12 millimeters, raise the lever upwards, send the wire into the terminal hole. Next, we return the lever to the opposite position, thus fixing the wire in the terminal.
The only substantial lack of WAGO is higher cost in comparison with traditional terminals.
This method of docking heterogeneous conductors resembles a bolt. However, instead of nut and bolt, a rivet is used, which forming an in-block connection. In other words, after fixing, it is impossible to remove the rivet without its damage.
To perform docking, we clean both conductor from insulating materialAnd also bend the wires in the rings. Next, we ride one of the rings on the rivet, then you wear a steel washer, then we reiterate the ring again, but the second conductor is already.
Rivet with one of the sides has a hat. Now you need to flatter the second side, having formed this second hat, which will act as a fastening. Rivet deformation is carried out either with a hammer or a special tool similar to pliers. The method of docking rivets allows you to get a very high quality connection.
If desired, two heterogeneous metal can be soldered. However, it will take compliance with some technological nuances.
As for the copper there will be no problems with soldering, but with aluminum it is more complicated. The fact is that as a result of soldering and under the influence of oxygen on a metal surface, Amalgam appears. This alloy film is incredibly chemically steady, because of which he does not have adhesion with the solder. To eliminate the film, you will need a solution of copper sulfate, Crohn battery and a fruent of copper wire.
On the wire from aluminum, we clean the site under the soldering, and then we apply a bit of a bit of vigor. The aluminum wire is fixed on the negative pole of the battery, and the copper wire is contemporary with one end on a positive pole, and the other end put on a copper cune. After some time, aluminum will cover the copper layer, to which the copper conductor can be attacked.
In most cases previously considered, a rigid fixation of conductor purified from the insulating layer will be applied. However, when docking copper and aluminum, one important should take into account technological nuance: aluminum under the influence of the load acquires plasticity, as specialists are expressed, begins to "flow". As a result of this process, the compound is weakening, and therefore the bolts must be regularly tightened. If you do not perform the bolt suspension on time, the terminal can simply light up due to strong overheating.
There are a number of rules, sticking to which, you can achieve a high-quality connection:
Note! It is not recommended to buy unnamed Chinese products. Connectors are too important detail to save them. It is best to give preference to well-known firms (as an example, a Swiss company "ABB" can be given.
As mentioned earlier, the conductors with a multitude of lived can not be shifted strongly. To connect stranded wires, sleeves or ordinary twists are most often used. About these methods Next, we will tell you a little more.
The sleeve is a protective cap from plastic, under which the hollow metal tip is located. First of all, you must remove the insulating layer from the conductor. Next, the veins are twisted into one whole, and the resulting "pigtail" is sent to the sleeve. Further, the sleeve is crimped (PASSTATIA is suitable for this operation). The tip of the sleeve is inserted into the terminal. To improve the reliability of the connection, the sleeve can be processed by the solder.
Among the electrical professionals, the twist does not use the reverence. However, there are situations when a twist is the most convenient way exit from the position (for example, to create a temporary connection or in the absence of necessary materials).
So, the twist of copper and aluminum is permitted only after the solid stripping of the aluminum surface. If the copper conductor has a lot of live, all existing veins need to be collected in one "pigtail". Also copper need to cover the solder - this will improve contact.
When twisting, it is important to prevent a break throughout. The ending is best to cover with insulating protective caps, which can be purchased in any store of household goods.
Note! A twist is not allowed in rooms with wet air.
So, in the combination of copper and aluminum conductors there is nothing complicated. It is only necessary to remember the price of the error: incorrectly connected wires can cause not only the refusal of electrical equipment, but also a fire.
How to connect a copper and aluminum wire - overview of popular methods
220.Guru.
With partial replacement of electrical wiring, extension of the conductor or replacing the burned area, a wire is used. It happens that in its material they do not coincide. Then the need arises to connect aluminum wires with copper. There are five ways to such a compound, and each has its advantages and disadvantages. Some of them require preliminary training of the conductor.
Industry produces two species, copper and aluminum wires for domestic purposes. The first have less resistance, which allows you to use a smaller cross section with the same load. They are more resistant to mechanical loads, it makes it possible to twist repeatedly, not to be afraid that they will turn around in place. In the latter, one advantage is a comparative cheapness. But it sometimes plays a key role. What can happen if the connection is poor quality?
Copper and aluminum have different characteristics.For example, a different expansion coefficient when heated. When the aluminum conductor passes a high current, it begins to "flow". If the veins during heating or cooling will be moved relative to each other, it will lead to the appearance of a gap between them. The gap, in turn, will lead to a discharge (spoke). Sparks can cause a fire. Along with this, copper and aluminum begin to oxidize, the resistance between them increases, the voltage due to this falls or can completely disappear. Voltage drops can badly affect connected devices.
There are several ways to connect. All of them have their pros and cons. Some require special equipment and skills, others are easy to use. Here are some of them:
It is strictly forbidden to use a twist in fire hazardous rooms.. This is the fastest and easy way. Two or more wires are taken and wind up relative to each other. It is impossible to leave one or more one veins straight. There is a rule - thick veins must have at least three turns, thin (from 1 mm and less) - five. To reduce the oxidation of the conductor, the copper core for the length of the twist is pecking. The same rule applies to multicore copper cables.
After the twist was performed, it must be protected from the environment by covering any waterproof varnish. This is necessary to reduce further excessive oxidation. Then isolate it with a tape or special caps that are sold in the store, and hide in the insulating body. But even all this does not give warranty that the twist will work flawlessly.
More time-consuming compared to twist. Requires a tool and some skill. It has greater mechanical strength. By electrical part it is better than a twist. Allows you to immediately connect a large amount of wires, and different sections. You can connect both single-core and stranded.
A bolt is used to connect to which conductors are put on turns. They are storm and wrapped in rings. Each lived if they are made from a different material, laid by a washer. The washer and spring washer is superimposed on the last conductor. The entire package is twisted with nut until the spring washer is straightened. Further squeezing can lead to an explorer cliff.
So that the washer does not cut the wires, they must be worn in a checker order (so that they do not lie on each other). If the copper wire is irradiated, the washers are not needed. The stranded copper wire also needs to be soldered, then in compression it will not break down.
After assembly, it is necessary to take measures to prevent closure with neighboring packages. Over time, it is necessary to check the state of the spring washer, if weakened - tighten the nut. Such a connection prevents sparking, allows you to display wires by different areas. If necessary, it easily disassembled and is going, without damaging the conductor.
Terminal compound is manufactured at the factories. It has an extensive range. Two groups can be distinguished:
Pads Have different forms and designs. The essence is to attach several wires to one conductor (plate, tetrahedral, etc.), which are inserted into special connectors and pressed the screw. As a rule, the pads themselves are attached to the base, creating stiffness of the structure.
The advantage of the pad is that preliminary actions are not needed, except for stripping lived. The connection occurs quickly, without requiring any skills. They are indispensable if the conductor is short (connecting the chandelier, restoring the interrupt wire). If you are in distribution panels, accounting panels - do not require isolation. Since each wire is connected separately, copper and aluminum wires can be used.
The following can be attributed to the following:
Terminali Recently, we found wide use. In its intended purpose, they are two species:
Reusable Terminal represents a fully isolated block. Instead of screws, a spring plate is used, which is pressed using a plastic lever. After that, the wire is inserted into the opening. In some embodiments, the plate has teeth, which allows the use of unnecessary wires. To pull the wire, it is necessary to raise the lever again.
Motherwise They have the same principle, but do not have a lever. Designed for one-time use. If the wire still pull out and insert again, the quality of the connection will be bad.
Benefits:
Disadvantages:
Perhaps the most time-consuming method. Requires special knowledge and skills. Special tools and fixtures are needed. To this method relate:
Rivech It is very similar to a threaded connection, with the only difference that the rivet is used instead of the bolt. The ends of the wires are cleaned of isolation and are cleaned with sandpaper. With a combination of aluminum and copper wires, the latter is revealed. It also applies to the copper stranded wire. After that, rings are made slightly larger diameter than rivet. In conclusion, when the whole design is collected (without intermediate washers), put on top of the washer. All this is squeezed with a terminal box. Isolated as well as threaded.
Soldering It is used where the high reliability of the connection is needed and its small resistance. Looks like a twist, but the wires are soldered. It is impossible to achieve this in the usual way for aluminum, so the wires must be prepared.
To do this, it will take a solution of copper vapor, a small non-metallic tank, a source of constant voltage at 9-24 V. In the container pour a solution of copper mood and lower the pre-purified conductors for a twist length. Copper wire is connected to "+" so that the electrons go from it, and the aluminum to "-". Turn on the power supply.
The voltage, of course, can be increased, the main thing is that the solution does not boil or there was no overload in the electrical circuit. You can reduce the voltage, then the process will proceed slower. All this works as long as the aluminum wire does not cover the copper film.
After that, both wires are covered with a layer of tin. A twist is done in 3 turns for thick wire and 5 - for thin (less than 1 mm). All this is carefully disappeared. It remains to be covered with waterproof varnish, isolate - and the connection is ready.
Benefits:
Disadvantages:
Now, knowing all methods for connecting copper and aluminum wires without soldering, you can eliminate this problem when it appears.
elektro.Guru.
Almost every electrician will tell and agree that the electrician is a science of contacts. In practice, it becomes obvious. A large number of problems in power supply is formed because of the large overloading of wiring, as well as due to weak contacts in the dispensing box. In this article, we will focus on the last problem, namely how to combine aluminum wires.
Aluminum has special properties of a metal that can cause difficulties when connected. Due to oxidation, an oxide film is formed on aluminum, which prevents the passage of electric current. This film is melted only at a temperature of at least 2000 ° C, and this indicator is above the melting point of the aluminum itself. Moreover, if we clean the oxide film by mechanical path, then after time it appears again.
If you want to solder aluminum, then this film will prevent solder adhesion with residential. Also, when welding, the film forms inclusions that negatively affect the quality of contact. Among other things, aluminum refers to the category of metals, which differ in high fluidity and fragility. As a result, contact should be completely protected from possible mechanical impacts. For example, if you connect aluminum with a bolted clip, then it is necessary to regularly tighten the contact, as aluminum, figuratively speaking, "follows" from the contact, which, in turn, weakens.
Are there any ways to reliably connect aluminum wire? Consider several common methods and decide how best to perform this work.
This connection method is very simple. It is necessary to clean the wire from insulation by 20 mm. After the custody, it is recommended to clean the fine-grained skin. Next, the bare core twist into the ring and insert into the clamping screw, which should be tightly spinning.
Options for screw connections
The minus of this method of connection is that due to the fluidity of aluminum, from time to time the contact must be tightened. Therefore, the connection site should be in an affordable place.
In this case, special terminal workers are applied. Due to the presence of a special spring, there is no need to regularly tighten the contact. Inserted stripped aluminum wire is securely held. There are terminal shots both disposable and reusable. Disposable are used to connect wires, without further disconnection. The wire inserts into the clamp hole, it does not pull it back. As for the reusable connection, the wire is easily pulled out if you press the special lever that holds the wire.
In rare cases, the aluminum wire can be connected by a twist method. Immediately it is worth noting that this method is very unreliable and even despite the fact that in Soviet times it was used relatively often. Partly explains this by the fact that in the past household appliances And accordingly, the load on the wiring was less. Now the picture looks different.
Moreover, the term of such a compound depends on different factors, for example, current load, humidity and temperature. If the temperature rises, the metal expands, which is expanding the clearance between the wires. This can lead to transitional resistance, the contact location will warm up and after that the oxidation is formed and, in the end, the contact will be completely violated. However, such a process continues for a long time, therefore, for temporary connections, the twist method is admissible.
When connecting aluminum, it is important to adhere to such rules:
Each of these methods has its place. Several factors affect the choice:
Consider each method of an inconsecting connection separately.
Fast and reliable connection method. Moreover, this technology is relevant if a large number of compounds should be made. However, this requires a welding transformer and skills.
Welding wire
The welding process is as follows:
Flux
Connection soldering method is simple. This requires components such as rosin, soldering iron, solders and additional elements. So, the wire twists, and after the soldering iron, apply solder on them.
For such a compound, special press clamps and sleeves will be required, which are hollow rods. For crimping, we clean the end of the wire, insert them into the sleeve and perform crimping in three places. Also additionally you can twist the wires.
Set for crimping
If the wire is aluminum, then use an aluminum sleeve, for copper - copper sleeve. If you connect aluminum with copper, then there are copper-aluminum sleeves on sale.
Compound 2 of copper and aluminum wires can cause some problems. The problem lies in the difference in potentials, the difference of which reaches up to 0.65 mV. When enhanced humidity due to this difference, the contact will be collapsed. Moreover, the contact will be heated, which can lead to deposits.
Using these techniques, aluminum can be connected to copper wires.
In this article, we reviewed several methods of how to connect wires with each other. If you know about other methods, then leave comments at the end of this article.
In the provided video material, you can learn about other subtleties of the connection of the aluminum wire:
kakpravilnosdelat.ru.
IN residential buildingswhich were built in soviet timesThe electrical wiring was performed by aluminum wires. Modern household network Professional electricians prefer to make copper wires. Therefore, we want it or not, but often it is necessary to deal with such a problem as connecting the copper and aluminum wire. Do not listen to those who will tell you that it is impossible to do this categorically. Of course, not all ways are suitable for a given case, however, the connection of electrical aluminum and copper wires is a completely solid task. The main thing is to fulfill everything right.
These two metal have different chemical properties, which affects the quality of their connection. But there were smart heads that came up with how to connect two conductors, excluding direct contact between them.
We will look at all the existing options for how to connect the copper and aluminum wire, but for starters, let's understand why it is impossible to make it an ordinary twist and what is the cause of such incompatibility?
The main reasons for the undesirable connection between these two metals will cover the aluminum wire.
the result of the cleaner of copper and aluminum - overheating of the connection, melting isolation, the possibility of fire
There are three reasons, but they all lead to the same result - over time, the contact connection of the wires weakens, begins to overheat, the insulation melts and the short circuit occurs.
The bolted connection of aluminum wires with copper is considered the most affordable, simple, fast and reliable. To work, you will need a bolt, nut, several steel washers and a wrench.
Of course, you can hardly apply this method to connect wires in the apartment distribution box, because now they are released miniature sizes, and the resulting electrical node will be very cumbersome. But if your house still costs the boxes of Soviet times or when you need to connect in the distribution panel, then such a bolted way is suitable in the best possible way. In general, it is considered an ideal option when it is necessary to switch absolutely incompatible veins - with a different cross section, made of various materials, stranded with single-core.
It is important to know that with the help of a bolted way you can connect more of two conductors (their number depends on how much the length of the bolt).
You will need to do the following:
Most importantly, do not forget between aluminum and copper wires to place an intermediate washer. If you connect several different conductors, it can not be installed between the veins from one metal.
Another advantage of such a compound is that it is discerned. At any time you can spin it and if necessary, then connect additional wires.
How to properly perform bolted wires in detail in this video:
Another good way to combine the copper and aluminum wire to combine the use of "Walnut" clamps. It is more correct to call the shout. These are already electricians nicknamed it with "nut" due to external similarity.
It represents a dielectric polycarbonate case, inside of which the metal core (or core) is located. The core is two dies, each of which has a groove for a certain cross section of the conductor, and an intermediate plate, all this combines bolts.
Such compounds are sold at any store of electrical products, they have different types that depend on the cross section of the connected wires. The disadvantage of such a device is not a tightness, that is, there is a possibility of moisture, dust and even small sera. For reliability and quality of the connection, it is better from above to wind the "nut" of the insulating tape.
The process of connecting wires with such a complication is as follows:
Practical example of using the walnut clamp is shown in this video:
The cheap and simple solution in the question, how to connect aluminum wires with copper, is the use of terminal blocks. You can buy them now - this is not a problem at all, moreover, you can buy not a whole section, but ask the seller to cut off the desired number of cells. Terminal pads are sold different sizes, depending on the section of the conductors connected in them.
What is such a shoe? This is a polyethylene transparent frame, calculated immediately into several cells. Inside each cell there is a brass tubular performance sleeve. From the opposite sides, in this sleeve it is necessary to insert the tips of the connected wires and clamp with two screws.
The use of terminal blocks is very convenient because it is always possible to cut off exactly so many cells, how many pairs of wires must be connected, for example, in one junction box.
Use terminal pads is very simple:
Why do you have to do everything alternately? You can immediately unscrew two screws, insert wires and spin. This is done in order to make copper and aluminum wires in touch with each other inside the brass sleeve.
As you can see, the advantages of terminal blocks are simplicity and speed of their use. This connection method refers to the terminated, if necessary, you can pull one conductor and replace it with another.
Terminal pads are not fully suitable for connecting multicore conductors in them. In order to do this, you must first take advantage of the sleeve tips that the bunch of lived.
There is another feature in the use of terminal blocks. Under the pressure of the screw at room temperature, aluminum can flow. Therefore, a periodic audit of the terminal and the contact connection suspension, where the aluminum wire is fixed. If this is neglected, the aluminum conductor in the terminal block is loosened, the contact will weaken, it will begin to heat up and sell, which can end with fire.
How to connect wires using a terminal block shown in this video:
Even faster and easier to combine aluminum and copper conductors in self-arc terminals.
The stripped veins need to be inserted into the holes of the terminal until it stops. There they are automatically fixed using the clamping plates (it firmly presses the conductor to the tinted tire). Thanks to the transparent terminal casing, you can control whether it went to the terminal. The lack of such devices is that they are disposable.
If you want a clip of reusable, use the lever execution terminals. The lever rises and frees the entrance to the hole in which it is necessary to insert the sheltered core. After that, the lever is descended back, thereby fixing the conductor in the terminal. This connection is connected, if necessary, the lever rises, and the wire is taken from the terminal.
In the best way in the electrical engineering market, the Self-Gone Terminals "WAGO" have proven. The manufacturer produces a special series of terminals, in which there is a contact paste "Alu-Plus". This substance protects the position of the contact compound of aluminum and copper from the manifestation of electrolytic corrosion processes. Data terminals you can distinguish on a special labeling on the packaging "Al Cu".
Use such terminals is also extremely simple. At the very climax, it is indicated for which length it is necessary to clean the insulating layer of the conductor.
The advantages and disadvantages of the use of Wago Terminals are described in this video:
The twist of copper and aluminum wires is not recommended. If without it, neither do not do, then to begin with the copper conductor, that is, to cover it with lead-tin solder. So you eliminate the possibility of direct interaction of aluminum and copper.
Do not forget that aluminum is very soft and fragile, can go on a break even with minor loads, so perform a twist extremely gently. Do not forget the connection to be insulated, it is best to use a heat-suite tube in this case.
We tried to tell you in detail whether the wires from aluminum and copper can be interconnected, as well as how to do it high quality and reliably. Choose the most suitable way for yourself depending on where this connection will be switched and operated.
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When repaired or replacing wiring, the situation often occurs when it is necessary to combine aluminum and copper wires. Contact should be very dense, and on a fairly large area. This is due to the fact that there will be quite high current here. This situation is particularly relevant when it is necessary to splicing the wires through which electricity is introduced into residential premises. How to combine aluminum and copper wires with each other so that the connection is reliable, efficient? Answers will be found in this material.
Figure 1. Simple wire connection methods
Is it possible to connect aluminum and copper wires? With aluminum, it is necessary to work carefully, it is connected with the specifics of the metal. It has peculiar characteristics, quickly oxidized. At the same time, a durable film from aluminum oxides is formed on its surface. The melting point is indicated about her strength - it is higher than that of pure aluminum. The film prevents the normal passage of the current. This method, as mechanical cleaning, does not help - the film layer is still restored.
There are still obstacles to a simple splicing - high level Fragility, severe fluidity. That is, the aluminum wire can not be bend as it is pleased. He will just break. With copper it is much simpler, as it is plastic. Chemical processes in the presence of moisture, such as electrochemical corrosion, destroy the metals in the places of their contact. The reason lies in the fact that copper and aluminum have different electrochemical potentials. Between them a big difference, equal to 0.65 mV, it exceeds the maximum permissible value.
That is why it is impossible to connect aluminum and copper wires with a simple method of twist. Many, not knowing this circumstance, still manage to twist. They are preserved simplicity of the process, no need for additional materials, except for insulating tape. At first, such a wire connection will work well. Then due to the difference in linear expansion coefficients originating from the daily temperature difference, the contact will begin to weaken. This will lead to an increase in resistance, start of oxidative processes. Subsequently, corrosion destruction will begin.
It is necessary to understand that all of the above will happen in no one day and may not be in one month. But it will definitely happen. Well, if everything is over. Because there are cases when fires arise from sparking. How to connect copper and aluminum wires to get reliable durable contact?
There will be additional devices for this. For example, the connection of aluminum and copper wires is possible by a twist method, if you have pre-littered the combined copper wire tin-lead solder. The difference in electrochemical potentials between them is low - 0.25 mV. Solder with aluminum alloys has a difference in 0.4 mV potentials. So the scrupter method is suitable for such a case.
It is necessary to regrehold if a stranded cable made of copper has to be connected with aluminum. It should be known that both wires must be accusing one around the other, although they have different degrees of rigidity. It is impossible to wrap one living around the other. The following are proposed twist methods and simple connections for wires.
Figure 2. Methods for twin connections
This method is the simplest after twisting. True, it requires a single bolt, nuts, two spring-loaded and three simple washers. Thus, durable compounds are obtained, which serve for many years. The advantage in this case is the possibility of connecting conductors of different sections, single-core, stranded.
The connection of aluminum wires with copper is performed in such a sequence:
Figure 3. Threaded connection
Depending on the diameter of the conductors for the best compound, the size of the bolt thread is selected. For example, for the vein section 2 mm optimal will be the diameter of the M4 thread. If the copper conductor is multi-core, it will be better to suck it, connecting all the veins in one harness.
Copper and aluminum wires can be connected to another way, where the nipper is used instead of screw and nut. How to join a ripple aluminum and copper wire? This will require a nipper, one spring and one simple washer. On the knob's hat, an aluminum conductor is put on her. The spring-loaded washer is put on top. Then they wander around the ripples loving copper core, which is put on a simple washer.
The crop process takes place with the use of special fixture - the cospel, which you need to have with you. Contact is solid, but such a connection is disposable. From the threaded conjugation, if necessary, to carry out a branch, adjusting another reliable contact. With a ripping, this version of the upgrade is impossible.
It is one of the most convenient accessories in order to connect the copper and aluminum wire. Terminals can be compounded not only aluminum and copper wiring, but also apply them to other combinations of metals, their alloys. Such a connection of copper and aluminum conductors has several advantages.
Figure 4. Pads and clamps with terminals
The wires are clamped with knights either with special clamping plates. Strategic conductors may be damaged if you pin it with screws. Plates in this regard are much more practical.
Alternative blocks can serve as terminal clamps of spring type. The Terminals of the German company Wago are especially popular. These devices can be disposable, reusable. Designed to splicing any lived, including copper and aluminum. Connect the conductors to the clamps are much faster and easier than twisted them.
No requirements are presented to conductors - they can be made of different alloys, have different diameters. Any combination of sections is possible - from 0.08 mm to 4 mm 2. They need to be simply cleaned to a depth of 10 mm. Reusable clamps can fix the veins, passing through themselves current up to 34 amps. Fixation is made by a special lever that should be lowered down. In order to pull the living back, the lever must be raised.
Such devices are used to connect chandeliers, wall lighting. They are convenient to use for wiring inside the connecting and junction boxes.
All that is listed above is applied to splicing inside buildings. But how to combine copper and aluminum cables outside? For this purpose, a special clamping mechanism called "Oreshk" is proposed. The clamping body made of plastic reliably protects the place of splicing and branching conductors from external influences. For reliable contact, several plates made from neutral to copper and aluminum metal are used.
Figure 5. Wire connector "Walnut"
As you can see, there are quite a few ways to connect cables made of different metals. For each of them you need easy rules to get a reliable connection. Of course, it is better to use only copper cables for modern wiring. But even in this case, there may be a splicing of different metals on entering.
When installing electrical wiring, the question of connecting copper and aluminum wires is sometimes faced. This issue is especially relevant in electrical work in the old residential foundation, where the main part of the power grid is made of aluminum wire. How to connect an aluminum and copper wire to avoid electrical wiring problems in the future will be considered in this review.
As is known, the cause of the problems of direct compound of copper and aluminum is electrocorrosive processes. In a dry environment, nothing will happen with direct contact, but with an increased humidity, a short-circuited galvanic element is formed at the connection site, in which the metals begins to play the role of the battery with a plus and minus. The metal itself is practically inspecting, as a result of which the network is breaking with a possible short circuit and the ignition of isolation. What in turn can lead to a fire.
In order to avoid this, for an indirect compound of copper and aluminum wiring, various kinds of contact devices are used.
All connection methods can be divided into 2 groups on the presence of wire contact:
Important! To connect aluminum and copper wires, it is recommended to use methods from the second group. It is allowed to use compounds from the 1st group under the condition of processing the copper wire. For example, it can be irresistible.
The main method of connecting wires in household conditions is sufficiently convenient because it does not require special tools and equipment. But in the case of a compound of aluminum and copper wire, this method must be used extremely carefully, following the following conditions:
There are three main varieties of twist: simple, bandage and twist groove. It should be noted that the best results will give a bandage twist. When performing a twist, it is worth considering that the amount of turns directly depends on the diameter of the wiring, so for the wire to 1 mm diameter, it is necessary to make a minimum of 5 turns, for large sections of at least three turns. In addition to moisture insulation, you do not need to forget about the electrical insulation of the twist, for this you can use special tips.
A high-quality twist will last long enough, but the correct guarantee can only be given to the use of indirect connections.
First you need to prepare ends lived. To do this, remove the insulation at a distance of 3-5 cm from the edge of the cable. It should be noted that the heat shrink tube is dressed on one of the wires, to a twist, upon completion of all operations, the tube shifts on open place And fixed on it. After cleaning the ends, you need to twist the wires on the proposed scheme. At the same time, it is necessary to ensure that the veins are mutually wrapped, and there was no lining of one cable vein to another.
For the convenience of twisting a stranded copper cable, its veins can and need to lose. It should also be noted that copper mud in any case increases the reliability of the junction of the twist. After twisting, the connection location must be covered with moisture-resistant varnish. Electrizolation can be carried out using a shrink tube or caps of caps with a soft clip or a cone spring.
Isolation of the ends of the wire cap with the cone spring
Important! Without extreme need to apply a twist to connect the copper and aluminum cable, it is not recommended. Currently there are quite a lot of more secure and reliable ways to combine copper and aluminum into one network.
In this case, a metal or plastic sleeve or a tip, which is fixed on the compound by press clamp, a special tool for crimping, dresses with a twist. The fixation in this case is carried out by crimping the compound with the material of the sleeve. The sleeves are a metal tube with insulation from PVC materials. The nozzles, as a rule, are plastic caps in which the connection is entered, after which the cap is crimped with press clamps.
Separately, it is necessary to note the connection using nozzles with a clamping ring or a cone spring. In this case, after twisting, it lived, the cap is dressed on the twist, after which rotational movements are screwed to the connection, after which it is simply crimped with pliers. In this case, a soft metal ring inside the cap tightly crimps the connection location. This option crimping is quite available for domestic use.
Reliable, although a somewhat bulky way of compounding copper and aluminum wiring is a threaded connection, in this case the veins are clamped on a thread basis. In order to avoid direct contact, the washer was laid between the random ends.
The advantages of this method of compound in simplicity and versatility. In this way, you can connect several electrically conductive sections. But at the same time, this type of connection is sufficiently bulky, in addition, it is very uncomfortable to isolate. But, at the same time, this type of connection requires only a bolt and nuts.
First of all prepare the ends of the wire. Isolation is removed at a distance of 1-1.5 cm from the cut, after which the rings are made of the rings with a diameter of slightly more than the diameter of the bolt or ripples. With these rings, the wire dresses on a ripper or threaded part of the bolt. A spring washer is labeled between aluminum and copper cable, this is necessary in order to be direct contact between these metals. After that the connection is fixed by tightening the nut or a riveter.
It is worth noting that this option is suitable for the splicing of the wires of sufficient length, when saving the length, which is often found when connecting the lighting electrical equipment to the short ends of the aluminum wire, as often happens in old apartments, it is better to use terminal boxes.
Conduct the wires in this case is carried out by a colored ripper consisting of a tube and core recorded by a riveter. To connect, the prepared veins with navita rings dressed on the rush tube with a gasket - a steel washer. After that, the riveter cripples are crushed, the core crushes the rumble tube, thereby squeezing the metal lived among themselves, thereby fixing the cable veins.
Contact in this case it turns out indefinitive, but at the same time durable and reliable. For this type of connection, a special tool is needed - a riveter and skills to work with it. This method is used mainly to work with wire breaks, the splicing of the wire ends in hard-to-reach places.
It is possible to connect the copper and aluminum wire with such a cunning method, which also requires a preliminary trafficking of the copper wire with a suspension: to hold the wire with two steel straps, with bolts on the edges. The advantages of the method: the ability to connect several branches at once, without increasing the length of the bolt. The curtain ends lived in this case are located between the planks. The method is applicable to the wires of one section.
Important! The connection with two steel straps requires mandatory external insulation, as well as the preparation of the copper wire with a suspension.
Comfortable and reliable connection method. The terminal block is a bar of an insulating material in which the jacks for the wire are placed. The fixation of the wire in the sockets is carried out by clamping bolts. An important feature In our case, the lack of contacts of the wires between themselves. For connecting copper and aluminum wire, only dumping.
The terminal box is a system of several separately placed terminal workers combined into one design and having several conclusions.
The advantages of this method of compound are:
At the same time, for mounting the hidden wiring in the wall, the terminal bar requires the installation of the junction box. Without a junction box, the installation of hidden wiring is invalid. But in this case, you can use a terminal box for hidden editing.
When working with a terminal box, it is important to carefully fix the ends of the wire in the nest, especially for aluminum wires. This is especially important when installing the box on the street or indoors, in which temperature fluctuations are possible.
Currently, both terminal blocks and terminals of reusable applications and one-time are produced.
Both reusable and terminals of single use are available in a wide range, including with a different amount of plug-in wiring branches intended for fixing the wire with a cross section from 0.08 mm² to 6 mm². Including, and in the form of ready-to-install, terminal boxes. This method of connecting an aluminum and copper wire is currently the most optimal in terms of reliability and ease of use.
Sing of the spring terminal and placement of the connection in the junction box
Terminal boxes with spring clamps were first issued by the German company WAGO, from which they received their name, but at present there are a large number of analogues, including counterfeit origin. For this reason, it is necessary to acquire spring terminal boxes only in electrical stores. When purchasing terminal boxes on the market, there is a high probability to purchase low-quality products that do not meet the claims.
To fix the wires in the terminal box, it is necessary to prepare wires, for this remove the insulation from them, the size of the bare part should be at least 0.5 cm. After that, the open part of the cable cable is inserted into the desired slot of the terminal box and is fixed in it by means of a spring clamp or screw. It should be noted that the fastening in the terminal box usually does not require additional insulation, but at the same time when they are located in the wall, a junction box is required. Thus, spring terminals have a number of advantages over the rest of the connections due to the convenience of connecting.
Thus, it is possible to combine copper and aluminum wire, but it is necessary to take into account the location of the cable, the environment. Two, copper and aluminum can be connected only in a dry room. With increasing humidity in the room, this connection may be unusable and more than cause a fire. The most optimal is the method of connecting wiring through spring terminal shots.
The main advantage of this method is stable fixation in any surrounding conditions. With all the advantages of a screw terminal, a threaded or a casual compound when operating under conditions of a sharp change of temperature, it is possible to loosen the contact under the screw. Due to the difference in temperature expansion of wires of wires. As a result of these changes, contact or short circuit is possible. Thus, with all the variety of methods for connecting copper and aluminum wiring, the most secure method on currentlyIs the use of self-arc terminal shots.
By repairing wiring in old houses, you can encounter a situation where you have to change large sections of wiring. However, in most cases, the old wiring is made of aluminum, and only a copper wire is available at your disposal. In general, to connect conductors from such different materials strictly prohibited, but it happens that there is simply no other output. Consider how to combine aluminum and copper wire so that there is no short circuit or fire.
To do this, it is worth straining your memory and remember the school course of chemistry and physics.
To begin with, remember what galvanic cell. Simply put, a galvanic element is a simple battery that generates an electric current. The principle of its appearance is based on the interaction of two metals in the electrolyte. So, a twist between copper and aluminum wire and will be the same battery.
Galvanic currents quickly destroy the material. True, in dry air their appearance is excluded. And if you make a twist to the outlet, then it will not fall apart in a few hours. However, subsequently trouble is provided with such wiring.
Over time, materials from which the wires are made are destroyed, along with it constantly resistance increases. If a powerful current consumer is connected to the outlet, then the twist will begin to heat up. With regular use of such a socket, the threat of fire is increasing.
Therefore, connect the aluminum conductor with copper stricter is prohibited. However, emergency situations arise when to make such a connection is simply necessary.
Consider several ways to combine aluminum and copper wire. These ways will help you successfully cope with difficult things.
Of course, this will not happen during the year, but if the compound must trade for a long time, then it is worth thinking about other bonding methods.
The principle of fastening by a twist method is that both conductors charked each other. For a better connection, the copper cable is brought out the solder. A multicore copper wire will have to be mandatory.
To connect copper and aluminum in this way you will need a pair of simple washer, one spring washer, screw and nut. This method is very reliable - contact between the conductors will be provided for many years. For this attachment it does not matter whether the cross-section of the wire nor its type is stranded or single-core.
From the end of the wire isolation is removed. The spring washer is worn onto the screw, then the ordinary washer is put on, then the ring of aluminum wires. He supports a simple washer. After that, a copper conductor is put on, and then a nut is screwed to the screw. She firmly compresses all the connection.
A multi-core cable must be brought before the connection.
This is a modern method of mounting wires. Although it loses a little in the reliability of the threaded method of compound The method has its advantages:
Last explanor, it happens that a small segment of the cable sticks out of the wall or ceiling. It is impossible to make a twist - there are very few wires. Yes, and the scrubs made on the ceiling lasts long, through some time the wires will simply break down. And the terminal block will be for a long time to hold both guides. Then the block completely eliminates the contact of two stripped conductors.
Installation is done like this: the end of the wire stripped from insulation (about 5 mm) is inserted into the terminal hole of the block, after which stop screw twisted.
The terminal block can not be hiding in the plaster or into the wall without a junction box.
This method appeared not so long ago. There are two types of such a compound: disposable and reusable. For the last connection in the terminal block there is a special lever. Thanks to him, the wire can be inserted and removed several times. Terminal blocks of this type have successfully combined copper and aluminum stranded wires of various types.
Widely applied to install chandeliers and wire connections in junction boxes. Some effort is required to insert the wire into the terminal block hole. To pull the conductor will need to make even more effort. For practical applications, it is better to use reusable models. In case of error, the connection can be quickly removed.
Perform such installation is very simple. First with cable isolation is removed (approximately 10 mm.). Then, on a reusable terminal, you need to raise the lever, insert the wire, and then return the lever in the original position. All simple!
Reliability is not inferior to the threaded connection and has its own advantages and disadvantages:
Installation is made using a special tool - a riveter. Aluminum wire is put on the rivet, then the spring nut, after which the copper wire and the flat washer. Then the riveter and the connection is ready.
It is worth mentioning that the connection area needs to be isolate.
Is it possible to solder conductors made from various materials? It is possible if comply with certain conditions.
With the soldering of copper problems will not arise, in contrast to aluminum. The surface of this metal is formed by Amalgam, manifests amazing resistance in the chemical plan. That is, the solder can not stick to it. This phenomenon often causes surprise at beginner electricians.
To solder two different conductors, it is necessary to be worst with a solution of copper vapor, the Crohn battery and a piece of copper wire. On the aluminum wire, the future place soldering is carefully preparing. Then on this place drip with a solution of copper cune.
The copper wire is connected to the positive pole of the "Crown" battery and lower in the copper vigor. Aluminum conductor is connected to the negative pole of the battery. After a while on aluminum, the copper layer is mounted, which the necessary wire can be soldered without any problems.
Once again it is worth noting that any connection of the wires must be exhausted.
You can place connections in special junction boxes.
If the connection is planned to do with your own hands, then you should not resort to the soldering method. It requires certain experience and qualifications. It is better to use another of the above methods for connecting an aluminum and copper conductor.
The most accessible and common methods were considered in the article. However, in the absence of experience in conducting such work, it is better to turn to professionals.
Any cable products have a conductive vein, which is made of copper or aluminum. Since these materials are characterized by excellent current and current conductivity, in the process of installation and connection, it is often necessary to compound them. On how to connect the copper and aluminum wire, without allowing errors, it will be discussed below.
To deal with all the subtleties of the procedure, it should be understood that it lies in a similar connection. After all, there are different opinions on what is categorically impossible to connect copper wires with aluminum.
Like any other metals with oxygen participation, aluminum and copper occurs. As a result, an oxide film appears on their surface. And if the copper cover almost does not interfere with the flow of electrotock, then the oxide is a serious barrier for this.
Wired compound of copper and aluminum, despite everything will become a push for the interaction of metals. Aluminum is characterized by a greater degree of activity. This means that between compounds, in the event of a moisture appearance, the so-called electrolysis occurs - the transfer of aluminum ions to copper. As a result, the conductor from aluminum loses its weight. It appears shells and emptiness, which are also amenable to oxidation and only accelerate electrolysis.
The result becomes almost destroyed conductor, which is made of aluminum. Since its cross section decreases, the degree of current density increases. In turn, it provokes the heating of the metal. Options for the outcome of such a situation are only two: either aluminum burns out at the point of connection, or a fire begins.
While some doubt whether it is possible to connect aluminum wires with copper, many are doing this successfully. Moreover, there are a number of major generally accepted methods, thanks to which you can eliminate contact between materials that are aggressive in relation to each other. Each of them requires separate attention.
The terminal bar for connecting wires can be equipped with a clamping or bolted mechanism. Such a design provides connecting to the materials of two types - aluminum and conductive. Between themselves, they are in contact with a steel plate. It is produced from a neutral material that is not inclined to join the reaction with aluminum - it is often plates from brass or tinned copper.
Pad for wires containing a bolt clamp is characterized by greater reliability and is used in low-voltage power circuits. Often, such a clamp is performed using "Out". It is a small splitting box, which is made of dielectric materials. Such a name device received due to its form. Inside it is a metal plate block, by means of which the contact between copper and aluminum wires is ensured.
Each of the methods described above is a detachable connection. This means that if necessary, you can repeatedly perform their disconnection and connection.
Electricity is not the area where you need to save. It is advisable to do everything carefully, the materials to select high-quality, to choose the sizes / diameters / denominations we suspend. Let's start with the fact that even to connect the conductors is necessary correctly. And choose the wire connection methods - it's not as easy as it seems.
Wire connection methods have about a dozen. In general, they can be divided into two groups: those that require special equipment or specific skills and those who successfully use any domestic master - they do not require any special skills.
The first group includes:
All these wire connection methods are performed mainly by specialists. If you have handling skills with a soldering iron or a welding machine, having trained on unnecessary trimming, you can do them yourself.
Some wire connection methods are more popular, others - less
Wire connection methods that do not require any specific skills are becoming increasingly popular. Their advantage is quick installation, reliable connection. Disadvantage - Need "Connectors" - terminal blocks, clips, bolts. Some of them are fairly decent money (WAGO terminals, for example), although there are inexpensive options - screw terminal blocks.
So, there are ways to connect wires that differ simplicity:
Among the professionals there are two opposite opinions. Some believe that new ways of connecting wires are the best way, as they accelerate the installation without compromising the quality of the connection. Others say that the springs someday can weaken and the contact will worsen. In this question, the choice is yours.
All the types described above are used when laying wiring, but the specific type is selected based on several characteristics:
Consider each connection method, the technology of its implementation and the feasibility of use in various situations.
One of the oldest and widespread types of compounds. To work it will take rosin, solder and soldering iron. The soldering process is:
Actually, on this soldering of electrical wires is completed. Not the most difficult process but requires certain skills. The main thing is to warm up the connection location is enough to solder the chapel between all the wires. At the same time it is impossible to overheat, otherwise the isolation is melted. This is the art - not to burn isolation, but ensure reliable contact.
When can I use a soldering? This method of wire connecting perfectly manifests itself in a minor electrician. When connecting wires in the junction box, it is no longer very convenient. Especially if there are a lot of wires and / or they are large diameter. Lead such a twist - the task is not for newcomers. In addition, when trying to lay a connection in the junction box, the soldering starts to collapse. Up to the point that some wires fall off. In general, the method is good when connecting the conductors of small diameters.
One of the most reliable ways of connecting wires - welding. During this process, the metal of individual conductors is brought to the melting point, stirred, after cooling is a monolith. Very good, this method works on large diameters or with a large number of connected conductors. It differs not just an excellent contact, which over time does not weaken and does not change its characteristics. It is also mechanically very durable - the fused part does not allow the connection to be collapsed even at high loads.
Drop at the end of the twist - melted aluminum
Disadvantages are also present. The first - just that the conductors are melted, that is, the connection is absolutely delicate. If you need to rebel to it, you have to delete the fused part and all start to start. To have the opportunity to do it, you should always leave a small ground along the length of the wires. The second drawback is a welding machine, the skills of handling it, special electrodes for aluminum or copper welding. The main task in this case is not to burn isolation, but to melt the conductors. So that it can be carried out, they are cleaned of the insulation of about 10 cm, tightly twisted into the harness, after which they weld at the very end.
Another lack of wire welding is a time-consuming process, which also requires jewelry accuracy in handling the welding machine. For the combination of these qualities, many professionals do not like this method. If you pull the wiring "for yourself" and know how to handle equipment, you can spend some time. Only pre-work on trimming, pick up the current and welding time. Only after you get everything you perfectly, you can start welding the wires "in real life".
Another method requiring special equipment - crimping wires by sleeves. The sleeves are copper and aluminum, different diameters. The material is chosen depending on the material of the conductor, and the size is selected by diameter and the number of wires in a particular connection. They should be filled almost all the space inside the sleeve, but it should be free space. The quality of the contact is depeted from the correctness of the size of the size of the sleeve. This is the main complexity of this method of connecting the wires: the sleeve should not be too big or too small.
Technology of work Such:
It seems simple, but it is in the selection of a sleeve and the presence of ticks all the complexity. You can, of course, try to blame passatias or pliers. But it is impossible to guarantee normal contact in this case.
In the first section of the article, we deliberately lowered the twist of the wires. According to the current standard, it cannot be used, as it does not provide proper contact and reliability of the connection. This method can replace any other wire connection methods.
Yes, on twists they made a wiring 20-30 years ago and everything worked fine. But what then were the loads on the network, and what now ... Today, the number of equipment in a regular apartment or a private house has increased at times and most of the equipment demanding power supply. Some species simply will not work under reduced voltage.
What is so bad twist? The wires twisted in the harness do not give a fairly good contact. At first, everything is fine, but over time, the metal is covered with an oxide film that significantly worsens contact. With insufficient contact, the connection place begins to warm up, the temperature rise causes more active formation of an oxide film, which further worsens contact. At some point, the twist heats up very strongly, which can lead to a fire. It is for this reason that it is better to choose any other way. There are which are even faster and easier, but which are more reliable.
All Wiring Connections described above - welding, soldering, crimping the sleeve - provide for their insulation, as the bare conductive conductors must be protected. For these purposes, the tape or heat shrink tube is used.
How to use the tape, probably everyone knows, but we will tell about the heat shrinking tubes. This is a polymer hollow tube, which, with an increase in temperature, significantly reduces its diameter (2-6 times, depending on the species). The size is selected so that the propulsion volume is larger than the diameter of insulated wires, and the post-witted one. In this case, a dense adjacent of the polymer is ensured, which guarantees a good degree of isolation.
Heat shrink tubes for insulation of conductors can be different diameters and colors
In addition to the size of the heat shrinking tubes, they are selected by special characteristics. They are:
The cost of heat shrink tubes is not very high - from $ 0.5 to $ 0.75 per 1 meter. Their length should be slightly larger than the length of the bare conductors - so that one edge of the tube was pulled on the insulation of the conductors by about 0.5 cm, and the second is 0.5-1 cm braided. After the tube is stretched, they take the heat source (you can use a lighter) and heated the tube. The heating temperature can be different - from 60 ° C to + 120 ° C. After the connection is covered, the heating is stopped, after which the polymer coolers quickly.
The time isolation of wires with a shrink tube takes a little - the account goes for seconds - and the insulation quality is high. Sometimes, for greater reliability, two tubes can use - slightly smaller and slightly larger diameter. In this case, first put on and warm one tube, then the second. Such compounds can be operated even in water.
This method also prefer to use electricians, but it can easily use a person who can hold a typical screwdriver in his hands. This is one of the first ways to connect electrical wires without soldering. Today, almost on each electrical appliance you can see the option of this connection - this is an output block to which the power cord is connected.
Terminal pads are a contact plate, which is posted in a plastic (polymer) or carbolite case. They stand very little, eat in almost any store selling electrical goods.
Terminal blocks are convenient, inexpensive, allow combined copper and aluminum wires, conductors of different diameters, one- and multi-
The connection occurs literally in seconds. The insulation is removed from the conductor (approximately 0.5-0.7 cm), the oxide film is removed. Two conductors are inserted into the nest - one opposite the other - and fixed with bolts. These bolts pressed the metal to the contact plate, providing a connection.
The advantage of this method of compound: can be connected wires of various sections, single-core with stranded. Disadvantage - only a pair of wires is connected. To connect three and more must be installed jumpers.
Another way of connecting wires that does not require special skills - installation of CAP caps. They are a plastic cone-shaped case, inside of which the spring is robbed. They are of different sizes - from 0 to 5. You can connect the wires of different diameters - on each package the minimum and maximum and minimum total cross-section of the connected wires is written. In addition, there are housings simply in the form of a cone, there are "ears" with the stops that make them easier. When choosing, pay attention to the quality of plastic - it should not be fed.
Connect the wires using PPE is very simple: clean the insulation, collect the wires into the bundle, insert the cap inside and start twist. The spring inside the cap captures the conductors, helping them twist. As a result, a twist is obtained, which is wrapped in the outside of the springs on the outside. That is, contact is obtained very high quality and good. This method of connecting wires with caps of PPE has long been in Europe and America, it came to us about 10 years ago.
If we need ways to connect wires without welding - consider PP
There is another way: first the wires are twisted, then the caps are put on them. This is a way of constructed by the Russian campaign, which produces these connectors for wires - KZT. But this technique requires more time, and the quality of the connection does not differ.
There is one more point: what length to clean the wire insulation. Manufacturers on this score give clear instructions - for each size of its length of the bare conductors. It is designed so that all conductors without insulation are inside the hull. If you do this, the connection does not require additional isolation, which is much accelerating the process. The coma of that extended lower part does not prevent the heat assignment and the compound is heated less.
Practicing electricians advise to clean the wires by 5-10 cm, and the leaving without insulation the twist to exhibit. It is argued by the fact that the area of \u200b\u200bcontact with this version is obtained more. It is so, but this option is heated stronger. And the standard solution with reliability. Contact problems E sometimes (with normal CAP).
The hottest disputes broke out exactly about Vago. One product is unconditionally liked, others do not like. And no less categorically. The opponents of using WAGO do not like the fact that the contamination is based on the spring. They say that she can relax. This will lead to a deterioration in contact and overheating. And give photos with molten clamps. Supporters of this method are testing tests and comparisons, they suggest that the correctly selected corporate clamp serves many years without signs of the deterioration of contact. Yes, and manufacturers suggest that, subject to technology, WAGO terminals can be operated for 25-35 years. It is important to choose the right type and parameters and not to buy a fake (there are a lot of them).
There are two types of Wago clamps. The first series is slightly less expensive, called WAGO. These clamps are suitable for connecting single-core and stranded wires with a cross section of 0.5-4 mm2. For the conductors of smaller or large sections there is another series - Cage Clamp. It has a very wide range of use - 0.08-35 mm2, but also a large value. In any case, contact is provided with a contact plate of good copper. The special form of the plate allows you to achieve reliable contact.
In addition, the spring-loaded wage clamps are detachable (222 series) and inepent (773 and 273 series). Connectors are convenient to put in those places where network configuration changes are possible. For example, in junction boxes. They have levers that are clamping or released. WAGO detachable terminals can be connected from 2 to 5 conductors. Moreover, they can be of different sections, such as (single-core and stranded). The order of connecting the wires is:
We repeat the same operation with another (other) wires. All this takes a few seconds. Very quick and convenient. It is not surprising that many professional electricians have forgotten other ways to connect wires.
Local series are distinguished by the structure: there is a clamping case and cap. The cap can be made of transparent polymer (773 series) or from opaque plastic (223). In the case there are holes in which the wires stripped from insulation are inserted.
To ensure normal contact, it is only necessary to correctly remove the insulation - exactly 12-13 mm. Such a requirement places the manufacturer. After the conductor is inserted, its bare part should be in the terminal bar, and the insulation should be restarted into the body. Under such conditions, contact will be reliable.
Another type of electrical wires with solid experience is bolted. It is called because it uses a bolt, nut and several washers to connect the wires. Contact due to the use of the washer is not bad, but the entire design takes a lot of space and uncomfortable in laying. It is used mainly if you need to connect conductors from different metal - aluminum and copper.
The procedure for assembling the connection is such:
So you can connect not only two, but also three, and more wires. Please note that it is necessary to delay the nut not only with your hands. It is necessary to use wrench, attach solid efforts.
Since different wires can connect, they can be operated in different conditions, The optimal way to choose considering all these nuances. We give the most common situations:
These are the most common options for non-standard connections.
