Surge arrester is one of the most widely known high-voltage devices used to protect the network.
Device Description
To begin with, it is worth explaining why, in principle, pulsed overvoltages arise and why they are dangerous. The cause of this process is a violation in the atmospheric or switching process. Such defects are quite capable of causing enormous damage to electrical equipment that will be exposed to such an impact.
Here it is worth giving an example on a lightning rod. This device copes with the discharge of a strong discharge striking an object, but it can not help in any way if the discharge enters the network through overhead lines. If this happens, then the first conductor that gets in the way of such a discharge will fail, and can also cause damage to other electrical equipment that is connected to the same electrical network. Elementary protection - turning off all devices during a thunderstorm, but in some cases this is not possible, and therefore devices such as surge arresters were invented.
What will use the device
If we talk about conventional means of protection, then their design is somewhat worse than that of an arrester. In the normal version, carborundum resistors are installed. An additional design are spark gaps that are interconnected in a sequential manner.
In surge arresters, there are elements such as non-linear transistors. The basis for these elements was zinc oxide. There are several such details, and all of them are combined in one column, which is placed in a special housing made of a material such as porcelain or polymer. This ensures the completely safe use of such devices, and also reliably protects them from any external influences.
It is important to note here that the main feature of the surge suppressor is the design of zinc oxide resistors. This design allows you to greatly expand the functions that can perform the device.
Technical specifications
Like any other device, the arrester has a basic characteristic that determines its performance and quality. In this case, such an indicator was the magnitude of the operating voltage, which can be supplied to the terminals of the device without any limitation in terms of time.
There is another characteristic - the conductivity current. This is the value of the current that passes through the device under the influence of voltage. This indicator can be measured only in the conditions of real use of the device. The main numerical indicators of this parameter are capacity and activity. The total indicator of this characteristic can reach several hundred microamps. The obtained value of this characteristic evaluates the performance of the surge suppressor.
Description of arrester device
In order to manufacture this device, manufacturers use the same electrical and design methods that are used in the manufacture of other products. This is most noticeable when inspecting the dimensions and materials used to make the case. Appearance also has some similarities with other devices. However, it is worth noting that special attention is paid to such things as the installation of a surge suppressor, as well as its further connection to general consumer-type electrical installations.
There are several requirements that apply specifically to this class of devices. The arrester must be completely protected from direct human contact. The risk that the device will catch fire due to possible overloads should be completely eliminated. If the element fails, then this should not cause a short circuit in the line.
Appointment and use of arresters
The main purpose of nonlinear surge arresters is to protect the insulation of electrical equipment from atmospheric or switching overvoltages. This device belongs to the group of high-voltage devices.
In these devices there is no such section as a spark gap. If we compare the operating range of the arrester and a conventional valve arrester, then the limiter is able to withstand deeper voltage drops. The main objective of this device is to withstand these loads without a time limit. Another significant difference between the surge suppressor and the conventional valve is that the dimensions, as well as the physical weight of the structure, are much lower in this case. The presence of such an element as a lid made of porcelain or polymers has led to the fact that the inside of the device is reliably protected from external environmental influences.
OPN-10
The device of this device is somewhat different from conventional arrester. In this embodiment, a varistor column that is enclosed in a tire is used. To create a tire in this case, it is no longer used porcelain or polymers, but a fiberglass pipe, onto which a shell made of tracking resistant silicone rubber is pressed. In addition, the varistor column has aluminum leads, which are tightened on both sides, and also screwed into the pipe.
Surge arrester OPN-10 belongs to the polymer group of devices. The main objective of this device is to protect the electrical equipment of switchgears. Elements with classes of 150 kV, with isolated or compensated neutral are also used to protect networks . You can use these devices outdoors in temperate and cold zones. Operating temperature range from minus 60 to plus 60 degrees Celsius. Installation work, as well as further operation of the equipment, can only be carried out in accordance with safety regulations.
Surge arrester OPS1
The OPS1 series of surge voltage limiters is also used for protection against lightning or switching overvoltages. Such a device is installed in the place of electric energy input to the object. It can also be mounted on the input of the main switchboard of the facility.
There are several classes of protection. Class B units are used to protect the electrical network from overvoltage after a direct lightning strike. Place of installation - at the entrance to the building, to the ASU.
Class C - specializes in directly protecting electrical equipment from processes such as residual atmospheric and switching effects. Place setting limiter - is the local supply panel.