Margareta Waltman спросил 2 года назад
Precautions For High Voltage Installation
High voltage electrical installation domestic domestic installation (Check Out Plantsg Com) power lines are usually located on utility poles but they may also be buried. No matter where you work it is crucial to be aware of the appropriate precautions for working with high voltage electricity meter installation.
The biggest risk is an electric shock. It can cause serious injury or even death.
Insulation
Insulation is a crucial component of high voltage installations. It must be maintained at the right levels to prevent failure and electric shocks. Insulation acts as an obstacle between electrodes and other circuit parts and makes it impossible for them to touch them directly. This can lead to injuries or even death.
Various materials are used to make insulation. The most popular was rubber material due to its simplicity to make and able to endure the most extreme conditions. Plastics have replaced rubber as the main material in high-voltage applications.
Some plastics are more durable than others, and you must consider the properties of each insulation material when deciding which one is the best for your project. Specifically, you need to know the strength of each, how tough it is and its flexibility, as well as how it handles moisture and abrasion.
These characteristics include thermal and chemical. Knowing the resistance to acid and alkalis as well as the capacity to withstand extreme temperatures, and electrical Domestic Installation the way it can absorb water are all factors that will help you determine the right material for your application.
It is important to ensure that insulation is resistant to heat and pressure when used in high voltage settings. This means that you need to choose a material that can withstand temperatures of at least 1000 degrees and also be resistant to humidity.
It is also important to look for insulators that resist fire and other dangers. This could mean a material that is waterproof and resistant to chemicals and oil, or even a material that is capable of defending against sunlight and Ozone.
It is important to search for insulators which can withstand the high tensions that come with power transmission. They could be suspended insulators, strain insulators, or shackle insulation.
These insulators are utilized to cover dead ends or sharp corners on power lines in which a heavy tensile load is expected. They can be made up of glass or porcelain discs, which are connected by metal links depending on the voltage.
Sharp Points
Conductors with sharp edges or sharp points increase the risk of dielectric breakdown during high voltage spikes. Fortunately, most manufacturers are aware of this problem and have made a habit of employing heat-shrink tubing with adequate dielectric strength. A well-designed system will be able to mitigate the risks of poorly trimmed insulation, which is a typical issue for high-voltage installers.
A good rule of thumb to ensure a secure, successful installation is to use a reputable contractor. The most reliable contractors have a well-constructed safety program in place and are well aware of the dangers that come with high voltages. The most challenging aspect of this process is to ensure that every employee is aware of the job they are assigned and is knowledgeable of high-voltage jargon.
Dust
It is essential to keep dust from entering high voltage installations. This will ensure safety and protection of personnel. Dust-proof constructions are a good option. It is also recommended that a protective cover be applied to the insulation.
Metal dust and insulating fibres are frequently combined in high voltage equipment. This is because they share similar characteristics of discharge and movement and a small amount dust can greatly reduce the breakdown voltage of an air gap.
It is still unknown the impact these impurities can have on the behavior of the air gap’s decomposition. A series experiments were conducted to better know the discharge and motion behavior of these materials.
As shown in Figure 10, the voltage at which the particles lift of metal dust varies slightly as the particle size decreases, but the motion law remains the same. The particles are moved mainly towards the upper electrode when the voltage is lower than 7 kV. They bounce violently between the electrodes when it reaches -14 kV.
To study the movement and discharge of these two materials in depth the tests were carried out with an ultra-fast camera. The results showed that metal dust and insulating fibres could be divided into three states: close and contact sate (or distant sate), Electrical Domestic Installation distant sate (or jump sate).
The dust of metal that was in contact with sate moving towards the electrodes. The area of movement created an area of dust columnar between them. The dust concentration in this area was low.
The insulating fibres on contrary, did not move when the voltage was low, but they began to lift as the voltage increased. The jumps between electrodes were fascinating.
During the test, the voltage was increased from -7 kV up to -16 in kV. Then the metal dust and insulating fibres started to move rapidly. As the insulating fibers lifted up, they bounced violently between the electrodes, causing an abrupt change in motion. At the same moment there was a significant amount of dust particles were released from the discharge area which caused an explosion.
Voltage Breakdown
Breakdown occurs when an insulator goes through an abrupt change in its electrical installation inspection properties. This happens when the electric field strength local to the material exceeds the material’s dielectric strength. This can happen in air or any other insulator and could result in burns, shock or fire.
Depending on the material used and the shape of the object different voltages can cause breakdown. This is why testing of the materials used in high voltage installation is essential.
For instance the breakdown voltage of a semiconductor device like a MOSFET depends on its drain-to-source current. A technique known as gate-current extract will determine the breakdown voltage.
Another method to determine the breakdown voltage is to place a sample of material between two electrodes, and then apply a high voltage. The voltage is then raised until it is at a point where it breaks.
The material of an insulator as well as the distance between electrodes and the force of the electric field at the contact determine the voltage at which it breaks. This is a significant factor in determining the safe voltage that can be applied to an insulation.
Engineers can utilize dielectric breakdown tests to determine the maximum voltage that their designs can handle. It can also be used to monitor changes in the insulator’s ability to resist voltage.
Copper and aluminum are more susceptible to breaking down than other. Aluminium can be subject to the breakdown voltage of 3 kV/mm if it is exposed to dry air at normal atmospheric pressure. This is the reason that aluminum cable is tested to less voltage than copper.
Other insulators like silicon may experience breakdown voltages as high as to 3.5kV/mm when exposed to dry air at normal pressure. This is due to the fact that silicon conducts at lower temperatures than aluminum.
Small impurities and bubbles can cause liquids to breakdown. They can cause an electrical field with a non-linear strength in the space between the electrodes, which could increase the potential for breakdown.
In this regard, it is often a good idea to protect the conductive surfaces of a device with dielectric materials such as glass or plastic. This will protect you from the possibility of breaking down and the dangers associated with it.
