A variety of cables and wires are used to connect the consumer of electricity to its source. The connection can be made on a permanent or temporary basis. With a temporary scheme, the load and the cable are equipped with detachable connector elements, which makes it possible to effectively solve the arising problem. For a permanent connection, the use of connectors is irrational both from the point of view of dimensions and cost, and other technical means are needed.
One of the most popular among them is the various tips.
Handpiece access provides:
- decrease in contact resistance by increasing the interaction area of the connected conductors;
- ease of breaking and subsequent restoration of the connection if such a need arises;
- reducing the risk of oxidation of conductors in the contact area.
The industry offers a wide variety of products of this variety, each of which is advisable to use for connection in certain cases.
The main design differences of handpieces
Tips are divided by:
- the type of materials that are involved in their manufacture;
- the method of attachment to the terminated conductor;
- the shape of the work area.
In terms of materials, there are copper, aluminum and combined (aluminum-copper) lugs. Examples of the execution of copper lugs for crimping are shown in Figure 1. The surface of the copper tip is often tinned to block oxide film formation. The materials of the tip and wire must be matched to eliminate the problem of galvanic corrosion in the contact area.
Combined lugs with a copper contact blade effectively solve the problem of connecting cables with aluminum conductors to electrical equipment.
According to the design of the working area, pin and lamellar, annular and open (horn) tips are distinguished, Figure 2. Ring lugs are additionally divided into washer and plate lugs, which reflects the shape of the blade.
In addition, sometimes there is a division into insulated and conventional ferrules.
Connector lugs (Figure 3) are designed for connection to plate contacts and are most effective with semi-permanent connections.
Mounting methods
Fastening to conductors is carried out mainly by crimping (crimping). With wires of relatively small diameter, the best results are obtained by using a specialized hand tool in the form of pliers, Figure 4. The working area of the tool has the shape of a hexagon, thereby achieving uniform coverage of the conductor from all sides.
The bolted method of fastening requires reference to the appropriate lugs (an example is shown in Figure 5), which significantly limits the popularity of its use.
The weld connection is geared towards high voltage technology and ensures maximum reliability of the installation area. Technologically the most difficult, because requires spot welding on specialized equipment.
Insulation of the contact area
It is advisable to provide the open section of the tip with insulation after its installation on the wire.
To complete this procedure, it is permissible:
- use more expensive ferrules, the skirt of which is provided with an insulating cover as in Figures 2 and 3;
- apply a heat-shrinkable tube (Figure 6).