Tips for crimping wires: secure connection of cables
Tips for crimping wires provide a reliable and tight connection of cables, which is one of the conditions for the safe connection of household appliances to the power grid. From this article you can learn in detail about all the features of these products, including their types, sizes and labeling. The text contains an overview of the technology of crimping with double and single tips, as well as products intended for connecting power cables.
Tips for crimping wires: main characteristics
Wire tips (endings) are universal parts used for the contact connection of cables. The use of such products has a positive effect on the functioning of the electrical circuit as a whole. There is a huge range of tips of various types on the market, so it is not difficult for consumers to choose the appropriate option for performing certain electrical installation work.
Tips for stranded wire allow you to create a reliable connection with various components of the electrical circuit:
- screw clip;
- terminal block;
- household electrical appliance;
- another cable.
The tips are excellent in circuits where strong vibrations often occur. They can also be used in cases where standard connection methods are not suitable. For example, if the cores are of insufficient length, it will not be possible to use the soldering or welding method. For crimping wires in such a situation, a tip or sleeve is simply installed on the bare end, after which this section is crimped.
Advantages of using tips:
Cable connection by crimping is used in production (connection of power lines) and in domestic conditions. The popularity of this method, in contrast to the use of conventional clamps, is due to its high reliability. In addition, it is much easier to connect wires with a tip than when using soldering or welding.
Pay attention! The size of the tips for crimping wires, as well as the sleeves, must be selected taking into account the main characteristics of the wire. These parameters include the diameter of the cable and the type of metal from which it is made.
How to decipher the marking of the tip for wires
To make it easier for consumers to navigate the offered range of tips, a special marking system is provided. It allows you to determine the material from which the part is made, as well as its purpose.
Decoding letter designations:
The decoding of the tip TML 70-10-11.5 looks like this:
A table containing information about common labeling options:
|TML||A universal product made of tinned copper, which has a high degree of protection from external factors|
|there||A tip designed for connecting aluminum wires. Has copper contacts|
|NSHVI||Bushing pin type of products with insulation, used in domestic conditions|
|that||A part made of aluminum, which is used exclusively for connecting wires made of the same material|
|SIP||Aluminum tip with tube insulation and a terminal made of copper|
Pay attention! Sometimes the marking of the tips on the wire contains the letter “O”. This indicates that the product has a viewing window. It is used to monitor the connection area and make sure that the wires inside the bushing are placed correctly.
Connectors for crimping wires: types of tips, sleeves and terminals
There are many variants of tips used for crimping. It is also necessary to take into account how the wiring will be installed. If it is assumed that the cables will be clamped in the circuit breaker, then it is better to use pin bushings for connection. On sale you can find tips with or without insulation. The same product variant is used for cables that are clamped using contact pads.
If the wiring will be attached under the nut-screw, then special connectors are needed in this case. These include the endings of the following types: U, J and O. After installation, the same screw is used to clamp them to the contact pad. There is another class of connections – tips of the “papa-mama” type. They are quick-release products that are very convenient to use.
According to the shape of the structure , the following types of tips for crimping wires are distinguished:
- tubular (bushing);
- in the form of an outlet (used for quick connection);
In addition, the tips are classified according to the type of material from which they are made.
Wire tips: types of products, their purpose
The connecting element is selected taking into account the type of wires on which it will be installed. The most common and popular are the following types of tips:
Copper versions of the products are designed for crimping cables made of the same material. For the production of these parts, one-piece tubes are used. On one side of the tip is the clamping part. On the other side of the connector there is a tubular hole where the wire will be inserted. Purpose of copper tips:
- connection to the circuit of input and distribution devices;
- installation of electrical appliances;
Aluminum products, like copper, are designed for wires made of the same material. On the one hand they also have a tubular hole, but on the other hand they have a contact blade.
Important! Before connecting the wires with a crimping tool for tips, aluminum products should be treated with quartz-vaseline grease. It will protect the contact area from oxidation.
Sometimes copper buses are used in distributors. In this case, aluminum-copper connectors are used. In these elements, the landing tube is made of aluminum, and the contact blade is copper. Friction diffusion is used in the production of these products. The technology of applying copper in a gas-dynamic way can also be used, during which the metal is sprayed over the tip, providing stable contact.
In bolt-type tips, fixation is carried out using a clamping bolt. To tighten it tightly, you will need a wrench. This method does not require crimping, since the bolt itself performs a contact connection.
The main types of crimping tips for copper wires
In the process of manufacturing copper connectors, pipes are cut accordingly. After that, a contact blade is formed on one side by flattening. It has a hole for fasteners, the size of which depends on the diameter of the bolt.
There are two types of copper tips for cables:
- without protective layer;
- with tinned coating.
Contacts with tinned coating are much more practical, since they have anti-corrosion protection. Due to this, this type of products has a long service life. Connectors with tinned coating are resistant to the aggressive effects of various acids:
They do not collapse under the influence of moisture, air and other negative environmental factors. Due to the presence of a protective coating, the level of electrical conductivity of the tips is reduced, but this does not prevent them from maintaining optimal performance.
As for copper connectors that do not have a protective coating, the oxidation of these products occurs much faster. Their current conductivity index is very low, which increases the resistance. As a result, the connection zone heats up.
The scope of application of copper tips extends:
- to create a contact between devices (possible use on a group of devices);
- forming a connection between the device and the electrical network;
- increasing the length of the cable by splicing wires.
Experts advise using crimping pliers for crimping the tips to install copper connectors on the wires. Despite the extensive selection of products offered by manufacturers, it is not always possible to choose an element of the required size. In this case, it is worth making the tip yourself. To do this, a copper tube of the desired size is selected, and then flattened at one end. For the mounting bolt, a hole of the appropriate diameter is made in it.
Important! Handpieces made in artisanal conditions are significantly inferior to factory products in their characteristics. It is very difficult to calculate what degree of load they are able to withstand, so it is not recommended to use homemade connectors on critical sections of the electrical circuit.
Using sleeves for crimping wires
In some cases, wire sleeves can be used as connectors instead of tips. If the splicing of cables in which the cores are made of copper is required, products marked GML should be used for work. This marking means that the sleeve is made of copper and protected by a tinned coating. Products with the GAO marking are intended for connecting aluminum wires. They are aluminum sleeves with a closed design. In addition, there are sleeves made of alloys. They are used in cases where it is necessary to connect aluminum and copper elements.
The connection by crimping wires with sleeves or tips is obtained better than splicing by soldering. A multi-core cable consists of several cores, each of which is hidden in its own insulating shell. For reliable contact, all of them must be bare, which creates certain difficulties when using soldering. There are no such problems with crimping, because in the process of compression, the insulation layer on each core is destroyed. Thanks to this, the connection is strong, and also provides better contact.
If the crimping will be carried out by sleeves, it is very important to pay special attention to the choice of products, in particular their material of manufacture. As a rule, current characteristics are prescribed on them. The main difficulties in the process of buying products arise when it is necessary to choose the appropriate size. Manufacturers in this regard offer a limited range. In addition, it is difficult for a person without special education to decipher the marking.
Crimping of wires using sleeves is performed in the same way as when using tips, however, more crimping will be required.
The main types of crimping terminals for wires
Connecting terminals can be divided into two categories: electrical and electrical. The difference between these products lies only in the magnitude of the current load that they are able to withstand. This parameter must be taken into account when selecting terminals for crimping wires during the installation or repair of the circuit.
Crimping pliers for wire tips: types of tools and methods of application
Functional purpose. Professional and household tools. Hydraulic pliers. Crimper for crimping Internet wires.
The most popular types of crimp terminals with the simplest design:
Knife–type terminals are the most common option. They are found mainly in household appliances, for example, refrigerators, irons or heating devices. Knife terminals are mounted on stranded wires, the cross-section size of which is in the range of 0.26-6 mm2.
Isolated and non-isolated variants are on sale. The color of the insulation material depends on the design capacity. It can be yellow, blue or red. Such products are used in pairs (“dad-mom”).
Important! The maximum voltage that such a connection can withstand is 5 kW. Therefore, knife terminals cannot be installed in large-sized power plants with high current capacity. It is also not allowed to install them in apartment electrical panels.
Fork terminals are used in secondary or power circuits. After their installation, screw fastening to tires or electrical equipment is assumed. This version of the products is considered a temporary option. It is allowed to use plug-type terminals in areas where contacts are often reconnected. Externally, such terminals resemble a fork with two prongs. They are used for crimping wires whose cross-section size does not exceed 6 mm2. They are presented in two versions – with and without insulation.
The ring-shaped terminals provide a very reliable contact. Like forks, they are subsequently fastened with screws. Due to the fact that the contact part has a round shape, the connection area increases. In addition, the probability that the tip will pop out is reduced. Suitable for low-current and power networks. The cross-section of the cables may be different. Ring terminals are aluminum, brass, copper-aluminum and copper.
The pin terminals have a detachable design consisting of a plug and socket. Blue products are designed for wires with a small cross–section – up to 2 mm2, and yellow – from 2 to 6.64 mm2.
Features of using NSHVI tips
Electrolytic copper is used for the manufacture of pin bushing tips. Insulation is located on the back of the product. To prevent corrosion damage to the metal, copper is treated with galvanic tinning. The size of these tips varies between 0.25-150 mm.
When crimping the NSHVI, time is significantly saved, which simplifies the process of connecting electrical devices. The tips are suitable for household use. They are designed for crimping stranded wires of any type. Manufacturers produce two types of NSHVI. Some tips are used to crimp one wire, while others are designed for two.
The products are marked as follows:
It is desirable that the size of the shank in the tip is slightly larger than the cross-section of the wire, i.e. its bare cores. So, for a 1.25 mm cable, you should purchase a 1.5 mm cross-section NSHVI.
Pay attention! NSHVI are designed exclusively for multi-core cables. It is not recommended to use bushing pin tips for crimping for wires with one core, since these products will not hold well on them.
Basic rules for crimping wires with bush type tips
It is possible to connect the wires qualitatively with a tip at home, without having professional skills and knowledge. To do this, you need to adhere to the basic rules:
Usually, the insulation on the wire is removed taking into account the size of the contact part of the tip. After stripping, the end of the core should coincide with the edge of the sleeve. To achieve this, 2-3 mm should be added to the length of the cleaned area. It is very important to choose the right size of the tip. In order not to make a mistake, you need to be guided by the color marking in which the insulating cuffs are painted.
There are some subtleties in working with insulated connectors. It is necessary to make sure that the insulating material on the wire goes all the way inside the cuff and is completely covered by it.
Preparatory work is carried out in the following order:
How to compress wire tips: a list of suitable tools
To install metal connectors on wires, it is not allowed to use tools that are not intended for these purposes. There are special crimping tips for wires. Each of them has unique capabilities, so it can be used in certain conditions. Scope of use of various types of tools for crimping wires with tips:
The tool, equipped with hinges, has an increased pressure force. At the same time, a person does not have to make much effort to install the tip. Devices with a ratchet mechanism are considered the most convenient in operation.
Important! Before you start working, you need to make sure that the diameter of the hole (matrix) on the tool is set correctly. Otherwise, the tip may be damaged during the crimping process.
Technology of crimping tips for wires: single, double and power
If the splicing of wires with the tip is performed for the first time, it is advisable to practice before starting work. To do this, you can use an unnecessary piece of cable. Otherwise, the master risks damaging not only the connector, but also the entire wire.
Recommendations for the use of single pin tips for wires:
Two wires can be connected to the phase using a single contact. If modular automata are being installed, special jumpers must be used for connection. As a result, two cables are connected to one contact. In this case, it is desirable to use the NSHVI for crimping wires with tips.
This procedure has its own characteristics:
- two cables are inserted into the cuff at the same time;
- for crimping, it is preferable to use press pliers having a matrix size of 6 mm2.
Otherwise, the process of installing a double connector is performed in the same way as a single one.
For crimping the tips of the power cable, it is recommended to use copper products with a tinned protective coating. Sometimes, after a piece of wire, its edge fluffs up and increases in size. If this happens, you need to remove the excess at the edges with a sharpener. The wire must be deployed so that the grinding wheel cuts off the excess along the veins, but in no case bends them.
Regardless of the type of tip used, it is not allowed to combine the crimping method with soldering. It is impossible for the contact part on the wires to be made of pure tin. Tips, as a rule, are crimped 1-2 times at a distance of 1-2 mm, sleeves – from 2 to 4 times.
Before installing the tip, you need to make sure that all the cores on the cut have the same length. Otherwise, the connection will be of poor quality. Sometimes the cores are damaged or broken, so the wiring should not be twisted before installing the tip. If this requirement is ignored, they will be transmitted during the crimping process, the current transmission will be disrupted.
In general, anyone can handle crimping cables at home. The main cause of errors is the mismatch between the dimensions of the wire and the tip. It is not recommended to use homemade connecting parts in work. It is also not allowed to cut the sleeve into two parts in order to save money.