Self-clamping and screw terminal blocks: advantages and disadvantages, scope

Spring or screw terminal blocks are widely used to create a reliable electrical circuit. Both options are reliable and provided for by special rules, while the more familiar twisting is still prohibited. The main requirement for them is to provide a reliable and safe connection with minimal loss of current.

Pros and cons of screw connections

The screw terminal block is a tube (copper, brass or made of analog materials) with clamps in the fuse box of the insulator (mostly plastic). The connection assembled with their help will be protected from all external factors, and the part can be reused.

Using such compounds, you need to know and take into account the following:

• The clamp itself is provided by the pressure of the screw through the washer on the wire. The second conductor is attached in the same way from the other end of the pipe. Contact between them is established through the conductive walls. Basically, the wires are simply inserted into the tube from both sides, and the screws are carefully tightened with a screwdriver.
  instagram viewer
• In addition to a screwdriver, you need a knife (or a special semi-automatic device) to strip the wires from the insulating layer. The stripped part must completely fit into the retracted part of the pipe. If the connection is stranded, you will need ferrules as well.
• During operation, the screw connection and contact reliability may be weakened. The contacts should be checked from time to time and the screws should be tightened if necessary.
• At the moment of fastening, there is a danger of crushing the core (especially if it is soft, aluminum). To neutralize possible problems, the wire should be doubled when placed inside.
• The clamps, marked with green screws, have teeth. These models are designed for grounding conductors.
• The screw allows you to quickly both fasten and unfasten the wire. But when the total chain is large and many connections are required, such operations take a lot of time.

The use of brass-based screw connections makes it possible to chain different types of wires and at the same time almost 100% guarantee that there is no oxidation.

Features of clamping models

Self-clamping terminal blocks are devices with one or another type of springs in a plastic case. They are not suitable for high electrical voltages., but even in everyday life with such parameters you can rarely meet. Themselves, these models are indispensable for mounting a chain in difficult, inconvenient places.

These devices have the following advantages and disadvantages:

• They tolerate vibration well, avoiding deterioration or interruption of contact.
• Cannot be used to align flexible conductors.
• Suitable for repeated fastening (if necessary, the spring can be pry off with a flat screwdriver).
• There are models that provide automatic fixation - just get the wires into the holes. This is convenient for serious volumes of work.
• Mechanical consumables are only slightly more difficult to use - you don't need a basic screwdriver.

It is believed that such fasteners provide, on average, a more durable and reliable contact. In any case, it will be possible to forget not only about twists, but also about soldering. For the price, they almost do not differ from screw.

Busbar distribution blocks

For domestic use, there are two most common types of electrical terminal blocks.

The indisputable advantage of both spring and screw is ease of handling and installation itself. However, in some cases mixed connections and whole busbar blocks are used.

It is necessary to name some aspects of their application:

• They are necessary to connect a large number of wires of different characteristics and can be based on both a screw and a spring principle.
• They can be used in an apartment or house, but their main purpose is to "work" in distribution boards. Therefore, as a rule, they do not have additional insulation and are rather large in size.
• Some complex tires allow for easy separation of the required amount mounts, which is convenient in situations where different types of installation are required - from one to several wires.
• Parallel internal jumpers reliably isolate adjacent wires from each other, eliminating short circuits.

Tires, contrary to popular belief, can be used not only by professional fitters and electricians. The rules for working with them do not differ significantly from those that are used in cases with single fasteners.

Domestic manufacturers now offer a wide selection of quality products. But fasteners can have different reliability characteristicsthat you should pay attention to. In most living conditions, this difference is unlikely to be significant, but it is still better to follow the instructions.