Connection of aluminum and copper wires

Most often, the need to connect aluminum and copper wires occurs during the replacement or repair of the existing electrical wiring. Also, the ability to do this will be very useful in the event of damage to the power cord of an electrical appliance.

There are several ways to solve this problem. Read the presented options, choose the method most suitable for your case and start working, observing the requirements of the technology.

We connect the wires with

Most often forconnecting wires using ordinary twisting. This is an easy-to-use method that does not require the use of additional devices. At the same time, twisting is the least reliable variant of connecting conductors, especially if they are made of different materials.

Each metal has a tendency to some change in its size with temperature changes. For different metals, the temperature expansion coefficient differs. Because of this material properties, a gap may appear when the temperature changes in the joint. It will lead to an increase in contact resistance, resulting in the release of heat, the cables oxidize and the connection will be broken.

Of course, this takes many years, but if your plans include the arrangement of a durable and high-quality network, it is better to refuse connection by the twisting method in favor of a more reliable option.

Before proceeding to connect the cables using the twist method, remember one important rule: the wires must wrap around each other. The option, in which one cable is straight, and the second one is upholstered, is absolutely unacceptable - such a connection will be absolutely fragile.

The method is suitable for connecting cables of different diameters. Stranding of solid and stranded wires is permissible, but in such a situation a conductor with several cores must be pre-brazed with solder in order to turn it into a single-core wire.

The cables are twisted, after which the connection is sealed. For sealing, a protective varnish with waterproof properties is suitable. For the connection to be of the highest quality, copper cable is recommended to be welded with solder before starting work.

The number of turns in the connection is selected according to the cable diameter. If the diameter of the conductor does not exceed 1 mm, we make at least 5 turns. When twisting thicker wires, we make at least 3 turns.

Threaded connection

Conductors made of different materials can be connected with screws and nuts. If necessary, this connection is very quickly disassembled and reworked. With a competent design, the threaded connection will be of very high quality and will continue to remain so throughout the life of the wiring.

An additional advantage of this option is the possibility of simultaneous connection of several conductors, the number of which is limited only by the length of the screw.

The method is suitable for connecting cables of different diameters and with different number of cores. It is only necessary to ensure that there is no direct contact between the wires of different materials. To eliminate it, a spring washer is included in the connection. In addition, such washers must be installed to eliminate the contact of the conductors with the nut and screw head.

The order of the conductors connection is as follows.

The first step. Remove the insulation from the cables. The required length is calculated by multiplying the diameter of the screw used by 4.

The second step. We study the state of veins. If they are oxidized, we clean the material to a shine, and then form the rings according to the diameter of the screw.

The third step. Alternately put on our screw spring washer, wire ring, washer, ring of the next conductor and at the end of the nut. We twist the nut until the washers are straightened.

Helpful hint! Preliminarily, the end of the copper cable can be brazed with solder. This will eliminate the need to lay a spring washer between the conductors.

We connect using the terminal block

The method of connecting conductors with special terminal blocks is gaining popularity. On reliability, this option loses the previous one, but it also has its advantages.

The terminals allow to connect wires as quickly, simply and qualitatively. Thus it is not necessary neither to form rings, nor to isolate connections - pads are designed so that the probability of contact of the exposed parts of cables is excluded.

The connection is made as follows.

The first step. Peel the insulation from the connected ends of the wires by about 0.5 cm.

The second step. Insert the cables into the terminal block and tighten with a screw. We tighten it with a little effort - aluminum is a soft enough and brittle metal, so it does not need an extra mechanical load.

Terminal blocks are often used when connecting lighting to aluminum wires. Multiple twists lead to a rapid break of such conductors, as a result of which, practically nothing remains of their length. In such situations, and useful shoe, because to connect it with just enough centimeter length of the cable.

Also the terminals are very well suited for connecting broken cables laid in the wall when the new wiring is not practical and the remaining length of the conductors is not enough to make connections by other methods.

Important note! Pads can be plastered only if they are installed in a junction box.

We use modern pads with spring clamps

Not so long ago in the market of electrical equipment and accessories modified terminals with spring clamps were presented. Available disposable( conductors are inserted without the possibility of their further removal) and reusable( equipped with a lever that allows you to get and insert cables) pads.

Terminal blocks wago	Current( A)	Number of pins.wire.	Conductor cross-section /( mm²)	Presence of contact paste
222-413	32	3	0,08-4,0	without paste
222-415	32	5	0,08-4,0	without paste

Disposable terminal blocks allow connecting single-core conductors with a cross-sectionin the range of 1.5-2.5 mm2.If you believe the manufacturers, these pads can be used to connect cables in systems with a current of up to 24 A. However, professional electricians are skeptical about this application and do not recommend to apply to the load terminals above 10 A.

Reusable same pads are equipped with a special lever( usually it is painted in orange) and allow you to connect cables with any number of strands. The permissible cross-section of the conductors to be connected is 0.08-4 mm2.The maximum current is 34A.

To make a connection using these terminals, do the following:

• remove 1 cm of insulation from the conductors;
• raise the terminal lever up;
• we insert wires into the terminal;
• we lower the lever.

Terminals without levers simply snap into place.

As a result, the cables will be securely fixed in the shoe. The cost of doing this connection will be more significant, but you will spend much less time working and relieve yourself of the need to use any additional tools.

We make an unbroken connection of the wires

The main difference of this variant from the previously discussed threading method is the impossibility of disassembling the connection without destroying the wires. In addition, you will have to buy or rent a special device - zaklepochnik.

Actually, the wires are connected with rivets. Strength, affordable cost, simplicity and high speed of performance are the main advantages of an all-in-one connection.

The rivet works in an extremely simple way: the steel rod is drawn through the rivet and cut off. On the length of such a rod there is some thickening. In the process of pulling the rod through the rivet, the latter will be expanded. The rivets of different diameters and lengths are available on the market, which allows selecting a device for connecting cables of almost any cross-section.

We work in the following order.

The first step. We clean the insulating material from the conductors.

The second step. We make rings at the ends of the rings with a size slightly larger than the diameter of the rivet used.

The third step. Alternately put on the rivet a ring of aluminum wire, a spring washer, then a copper cable ring and a flat washer.

Fourth step. We insert the steel rod into our rivet and press the tool handles with a force until it clicks, which will indicate the cutting of the excess length of the steel rod. The connection is now ready.

You have got acquainted with the main methods of self-connection of aluminum and copper wires. Each method has its own peculiarities, disadvantages, advantages and preferred applications. Choose the most suitable option, follow the instructions of the instruction and very soon all necessary connections will be ready.

. Good work!

Video - Connection of aluminum and copper wires