Wire clamps: existing types of clamps + detailed connection instructions

Electrical work related to electrical networks is inevitably accompanied by installation, maintenance, and repair.In turn, the listed service forces you to use clamps for wires of different configurations.

These are, as a rule, relatively small parts designed to work with different types and sizes of conductors. The base of existing clamps is large and it is quite difficult to cover the entire range of such accessories. However, there is a so-called “popular” set that is used most often.

Let's look at the most popular types of clamps, outline the scope and specifics of their application, and also provide detailed instructions for connecting wires using such technical accessories.

Popular types of electrical clamps

In practice, the installation of electrical circuits uses special technical accessories - clamps of various designs. The specific application is determined by many criteria, ranging from the purpose of the network to the technical and operational parameters of the connections.

Type #1 - simple terminals with screws

What is remarkable about this type of accessory is that the terminal allows you to make a reliable connection without clearly disturbing the structure of the conductors. In this case, it is permissible to connect conductors based on different metals, for example, copper and aluminum.

Single-way terminals on a polypropylene (polyethylene) base are considered widespread in everyday practice.

The design is a metal, usually brass or bronze, short channel of small diameter, equipped with two threaded holes for fixing screws.

The simplest design of a screw clamp based on a polypropylene base. A metal bushing with locking screws that tighten the ends of the wires inserted inside the bushing is “hidden” under the polyethylene casing.

Such a metal channel is embedded inside a polyethylene shell, which has good insulating properties. In order to connect two separate conductors, the end parts of these conductors are placed in the channel on both sides, after which they are securely fixed (pressed) with screws.

There are different channel configurations terminals, based on installation parameters such as:

• conductor diameter,
• current characteristics,
• insulation class,
• number of contact points.

In fact, the selection of such accessories is possible for any technical conditions, especially those that are relevant for the household sector.

Type #2 - self-tightening and lever clamps

This type of connecting accessories is characterized by increased user convenience. For example, if you use disposable self-tightening clamps, simply insert the stripped end part of the wire all the way inside the clamp hole.

The plate-type design is self-aligning into the “clamp” position. During installation, it is enough to lift the plate with the blade of a screwdriver and insert the end of the wire or simply insert, in the case of one core, without the help of a screwdriver

Inside the structure there is a spring plate, which is installed with the cutting part in the “opposite direction” of the conductor. When the wire is inserted into the channel all the way, the plate is pressed with a metal core and the “countermoving” part cuts into the body of the wire.

To release the conductor, you need to press the plate with a screwdriver through the hole in the second row. These types of clips are not reusable. They are enough for 3-4 times of repeated connections.

Convenient configuration that uses special levers instead of traditional screws. This design option presses the wire with a plate, which is fixed with a lever

Numerous repeatability of connections is supported by similar designs, but supplemented with a press lever. The practical application of such accessories is simple.

It is enough to lift the lever perpendicular to the channel, insert the stripped conductor and lower the lever until it clicks. The wire will be securely fastened. Accordingly, the reverse operation is performed if the wire is released from the channel.

Type #3 - connecting insulating clamps

Accessories of this kind provide the connection of conductors of relatively small diameter. In fact, connecting insulating clamps (technical abbreviation - PPE) represent a kind of hand tool of the same twist.

Two or more pre-stripped ends of the conductors are formed into a group and “covered” with a connecting insulating cap until it stops. Then the cap is turned several times.

Inside such a system there is a spring spiral having a conical shape. As the cap is screwed on, the spiral wraps around a group of ends of the conductors and pulls them tightly into a single knot, pinching them inside.

A cap type of element, with the help of which a completely reliable connection of conductors of a relatively small cross-section is organized. As a rule, such elements are used on electrical networks with a voltage of 110-220 volts

Cap connectors are used, as a rule, on electrical wiring of relatively low power.Very often this type of clamp is chosen during installation household in-house electrical networks.

There are two types of caps:

• cone-shaped straight shape without thrust protrusions;
• cone-shaped straight shape with persistent protrusions.

The second configuration, as a rule, has a slightly larger diameter and is intended for fastening conductors of larger diameter.

Type #4 - piercing clamping element

On electric lines with power up to 1 kV, piercing type clamps are often used. This type of accessory allows working with conductors with a cross section of 1.5 – 10 mm² on branch lines or work with conductors 16 – 95 mm² on main trunk lines.

The design is a metal plate girth covered with insulation, which is compressed by pressure from a thrust bolt.

The plates that wrap around the conductor are equipped with sharp metal teeth, which, under pressure, pierce the insulation of the wire and dig directly into the body of the conductor.

A clamping structure, the operating principle of which is based on piercing the conductor insulation with subsequent tight contact with the metal core. Such products are usually used on high-voltage networks

The advantages of such structures are obvious. Working with them allows you to avoid labor-intensive operations of removing insulation. In addition, the design of the piercing clamps is made in such a way that it allows you to perform work without turning off the power supply to the line.

Piercing type clamps provide a high degree of sealing against atmospheric influences.

Polymer insulation, resistant to ultraviolet radiation, is reinforced with fiberglass to enhance strength. There is an insulating rubber cap for the tip.

View #5 - clamp between bolt and nut

Often, on power networks, installers use a simple but quite reliable method of fastening through a regular bolt clamp.

To organize a connection of this kind, you need always available parts:

• bolt of suitable diameter;
• nut to bolt;
• two washers according to size;
• lock-nut.

In a similar way, it is permissible to connect dissimilar electrical conductors, for example, copper and aluminum.

An example of creating a connection between conductors of different metal structures using a conventional bolt clamp. The problem of separating the direct copper-aluminum bond is solved by simply adding an extra washer

However, theoretically, such a combination is not recommended in electrical practice due to the different chemical properties of the metals.

Clamps for other purposes

In addition to the designs of clamps intended for connections electrical conductors, there is a variety of this kind of accessories for other purposes.

Anchor clamps for fastening

Designs of clamps for fastening (suspension) of wires with a cross-section of 2 – 25 mm² in the amount of two to four cores. Structurally, the anchor accessory consists of a polymer body equipped with a self-adjusting clamping wedge.

A device whose design also assumes the role of a clamp. However, in this case we are no longer talking about connecting the conductors, but about the installation method - fixing it in a suspended state

Two configurations of anchor clamps are available:

• for self-supporting systems;
• under an isolated carrier neutral.

The mechanism has an easy-to-open bow, making it convenient and easy to install the clamp on brackets, hooks, and then attach electrical wires to the body of the clamp.

Wire clamps for test needs

Often the practice of electronics and electrical engineering involves the use of clamps for so-called “test” purposes. Traditionally, such accessories are “crocodiles” - jagged sliding (push) metal structures.

The toothed part of such a clamp remains open, while the pressure part is insulated with PVC material.

Another option for the design of clamping elements belonging to the class of equipment under test. So-called alligator clips are used to make a temporary contact, for example, to measure voltage

Such accessories are used for temporary attachment (engagement) to wires, for example, for the purpose of measuring current or network voltage.

This type of clamp can be divided into two categories - for low-voltage electronics and for high-voltage electrical networks. Both categories differ from each other in the limiting technical parameters for current.

Instructions for connecting wires with a clamp

Actually, the procedure for performing the work, in this case, is connecting wires using various types of clamps, simple and clear. It is quite possible to do it on your own.

The first step is to bring the working conductors to the interface. AND remove insulation at the area where the clamp is inserted into the sleeve.

Next, carefully clean the exposed end part to a characteristic shine - it’s better for work select stripper.

The procedure for stripping the end of a wire before making a connection using a screw terminal.It is worth noting that this procedure is much more convenient to perform with a special tool for removing insulation

Now you need to insert the prepared ends inside the clamp sleeve and secure.

If necessary, such a connection can be additionally insulated.

The procedure for clamping stripped parts of wires inserted into sleeves. Exactly the same operation is performed on the opposite side of the block. Often work with clamps is carried out in power panels or distribution boxes

The work of connecting conductors is even easier when using a piercing type clamp or a self-aligning spring type clamp clamp type VAGO.

Conclusions and useful video on the topic

How to connect wires and what accessories to use in this or that version of the paper clip? The video talks about this in detail and shows:

A variety of mechanical elements that act as a reliable clamp greatly facilitates installation and adjustment work. Thanks to the use of such elements, the level of safe operation of electrical networks increases.

The only caveat is the correct use of such accessories, since a discrepancy in technical capabilities threatens to negate all the advantages of the clamps.

Do you have experience selecting and using wire clamps? Or want to ask questions on the topic? Please comment on the post and participate in discussions. The feedback block is located below.