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Precautions For High Voltage Installation

High voltage electrical power lines are often placed on utility poles, however, they could be submerged as well. Whatever location you are working in it is essential to be aware of the appropriate safety precautions when working with high-voltage electricity.

An electric shock is the most hazardous. This could cause serious injury, or even death.

Insulation

Insulation is an essential component of high voltage installations. It must be maintained at the proper levels to avoid failure and electric shocks. Insulation acts as an insulator between electrodes and other circuit parts and makes it impossible for them to touch them directly. This could lead to injuries or even death.

Various materials are used to create insulation. Rubber was the most well-known material due to its easy to make and could withstand the harshest conditions. However, today, plastics have replaced it as the material of choice for the majority of high-voltage applications.

Certain plastics are more resilient than others. It is important to consider the properties of each material before deciding which one is best suited to your project. Specifically, Installation you need to know the strength of each, how tough it is as well as its flexibility and how it fares with abrasion and moisture.

These properties include thermal and chemical. These properties can aid in choosing the appropriate material for your requirements.

When working with insulators within a high-voltage environment, you must be sure that they are constructed of materials that can withstand the heat and pressure. Choose the material that is able to withstand temperatures up to 1000°C as well as humidity.

Additionally in addition, you should look for insulators that are resistant to fire and other hazards. This could be the use of a material that is waterproof as well as resistant to oil and chemicals or even a material capable of defending against sunlight and the ozone.

It is important to search for insulators that can withstand the extreme tensions that are associated with power transmission. They can be suspended insulation, strain insulators or shackle insulation.

These insulators are employed to prevent dead ends or sharp corners on power lines in which a heavy tensile load is expected. They can be made up of ceramic or glass discs which are joined by metal links based on the voltage.

Sharp Points

Conductors with sharp edges and points increases the chance of dielectric breakdown in the event of high voltage spike. The majority of manufacturers have recognized this and made it a priority to utilize heat-shrink tubing with the right dielectric strength. A well-designed system will be able to reduce the dangers of improperly cut insulation which is a common problem for high-voltage installers.

A common sense guideline for ensuring a safe, efficient installation is to employ an experienced contractor. The best contractors have a solid safety program in place and are well versed in avoiding the hazards that come with high voltages. The most challenging part of this process is to ensure that every employee is aware of their role and is aware of the terminology used by high voltage companies.

Dust

It is essential to keep dust from getting into high voltage installations. This will ensure safety and protect personnel. Dust-proof constructions are a good option. A protective cover for insulation is highly recommended.

Metal dust and insulating fibres are frequently combined in high voltage equipment. Because they share similar characteristics of movement and discharge characteristics even a small amount of them can reduce the breakdown voltage of an air gap that is open.

However, the impact of these two impurities on breakdown behavior of an air gap is still a mystery. To better understand the phenomenon of discharge of these materials, a series tests were conducted to investigate their discharge and installation motion both separately and together.

As shown in Figure 10, the voltage at which the particles lift of the metal dust is slightly different as the size of the particles decreases, but the motion law is the same. When the voltage is less than 7 kV the particles are primarily moving towards the upper electrode. They bounce violently between electrodes when it is 14 kV.

A series of tests using the help of a high-speed camera were done to see the movement and discharge of these materials in greater detail. The results showed that metal dust and insulating fibres could be classified into three different states: close-and-contact sate (or distant sate) distant sate (or jump sate).

When the dust of metal was present in contact sate, it moved towards the upper electrode , and its movement area formed a certain columnar dust region between the electrodes. The concentration of the dust in this area was relatively low.

The insulating fibers, however they didn't move when the voltage was low, but started to lift as the voltage increased. The resulting jumps between the electrodes were very interesting.

During the test, the voltage was increased from 7 kV to 16 kV. The metal dust and insulating filaments began to move rapidly. When the insulating fibres rose their weight, they bounced around the electrodes and caused an abrupt change in their motion. A huge amount of dust particles were also expelled from this area and caused an explosion.

Voltage Breakdown

Breakdown occurs when an insulator experiences an immediate change in its electrical properties. This is due to a local electric field strength that exceeds the dielectric strength of the material. This can occur in air or any other insulator and could cause burns, shock or even fire.

Depending on the material and shape of the object the shape and material of the object can lead to breakdown. It is therefore important to test the materials used for high voltage installations.

For instance the breakdown voltage of an electronic device like a MOSFET is determined by its drain-to-source current. A technique called gate-current extract will determine the breakdown voltage.

Another method of measuring the breakdown voltage is by putting the sample of material between two electrodes and applying a high voltage to it. This voltage is then increased until the material begins to break down.

The breakdown voltage of an insulation depends on its material and the distance between electrodes, and the electrical field strength at the contact. This is a crucial aspect in determining the amount of voltage is safe to apply to an insulation.

This is the reason dielectric breakdown testing is so vital, as it helps engineers to determine the highest possible voltage for their designs. It is also utilized to observe changes in the insulator's ability to resist voltage.

Some conductors, such as aluminum and copper are more susceptible to break than other. Aluminium can be subject to breakdown voltages of up to 3 kV/mm when exposed to dry air at a normal atmospheric pressure. Aluminium cable is rated at a lower voltage than copper due to this.

Other insulators, like silicon, can be subject to breakdown voltages of up to 3.5kV/mm when they are exposed to dry air at normal pressure. This is because silicon conducts better when exposed to low temperature than aluminum does.

In liquids, breakdown may be caused by bubbles, or tiny impurities. These can cause an electrical field that is non-linear in the space between the electrodes, which may increase the breakdown potential.

In this regard, it is usually beneficial to protect the conductive surfaces of a device with dielectric materials, such as glass or plastic. This will help protect against the possibility of it disintegrating and the risks that can result from it.