To transfer electricity, wires are mainly used from copper cores, since copper has a lower value of resistance to electric current. One of the common types is the PWAM wire. This type of wire is used to power automotive equipment.
Pvam wire
The wires have one conductive core made of copper and consisting of many small wires twisted together. Due to numerous wires, cable flexibility is increased and resistance to electric current is reduced. The insulation is made of polyvinyl chloride. Depending on the operating conditions, it is performed in three types:
- For conditions with elevated temperature, the insulation is heat-resistant; during testing, the temperature is applied slightly higher than the operating temperature.
- For conditions of use with a low ambient temperature, the insulation is frost-resistant, and during testing the temperature is applied slightly lower than the temperature at which the cable will be used.
- For conditions with a significantly elevated temperature, in order to avoid ignition of the insulation, it is performed specifically for fire hazardous rooms and mechanisms: in its manufacture polyvinyl chloride with reduced combustibility is used. Such wires are used to power electrical equipment near parts of mechanisms with high temperature.
The insulation is painted in one or more colors, depending on the conditions and requirements of the customer. The primary color always occupies more than 50% of the painted insulation of the PVAM wire. The auxiliary color is sometimes made of several different colors of stripes parallel to each other.
For special operating conditions, a screen is used. This is required for the transmission of signal pulses in order to reduce losses when passing through a PCAM wire. The screen is made of thin copper wire in the form of a braided grid with tin-plated tin solder. Sometimes the screen is made in the form of a foil film.
Characteristics
The PVAM wire has the following characteristics:
- operating temperature range from -40 to +105 ° ;
- at elevated temperatures up to 125 ° C, the wires are able to maintain resistance for up to 48 hours, and at a temperature of 150 ° C for 15 minutes;
- at a temperature of +80 ° C, the wires are not subject to deformation;
- the wires are not subject to deformation during bending, erasing, creases, twisting;
- construction length in the manufacture does not exceed 100 m;
- the service life is up to 8 years, subject to operating conditions, the warranty period is 3 years;
- maximum available operating voltage - 5 kV;
- not susceptible to various chemical compounds and mold damage.
Labeling Explanation
When deciphering the labeling of any cable products, you should pay attention to the letter designation. The following values correspond to this PVAM wire:
- P - means a wire;
- B - means increased flexibility of the wire or cable;
- A - means the scope of this wire, namely, automotive;
- M - this wire has a copper conductive core.
At the end of the letter values, a numerical indicator of the diameter of the cross section of the copper core is indicated. Sometimes, after the cross-section value, the GOST value is indicated, according to which the wire was produced and passed the test.
Application
PGVA or PVAM wires are designed to transmit electricity in automotive and tractor equipment, as well as in other road transport mechanisms. This wire has one conductive core and is used to transmit low voltage up to 48 V DC. They are used in areas with high temperature. Before use at the factory, the PVAM wire is tested according to the climatic conditions during operation. Sometimes, according to customer requirements, these wires are shielded.
This type of wire is designed to power equipment in a temperate, tropical, and cold climate.