What is an surge arrester?
An surge arrester can be described as a safety device that limits the voltage of equipment through the discharge or bypassing of the surge current. It blocks the flow of electricity to continue to follow current until ground and can perform the functions specified in ANSI C62.11. C62.11. An arrester does not absorb lightning or stop lightning. It redirects the lightning, restricts the voltage and safeguards equipment in parallel.
Surge arresters can be used in a variety of ways they can be used for, from protecting the home from damage to an utility substation. They can be found on circuit breakers in homes, inside pad-mounted transformers, and on pole-mounted transformers, in pole-mounted riser poles as well as substations.
Why should you use a surge-controller?
The distribution power line is likely to witness various voltage surges. Lightning is the most significant source of these surges. It is estimated that there are 100 lightning strikes that occur on surface of the Earth every second. Lightning is an unpredictable and unpredictable phenomenon.
Other causes of voltage surges are the phenomenon of switching surges, as well as temporary overvoltages. The term "switching surge" refers to the overvoltages generated due to variations in the operating conditions of the system. They constitute the most common voltage surges for station-class arresters. Switching surges are the capture of energy, and then the release of energy. The temporary overvoltages are caused by ground faults on a single phase. The voltage then increases on the unfaulted phase until the fault is removed.
What does an surge arrester function?
Metal oxide varistor (MOV) surge arrester is a set of varistor made from metal block. The MOV blocks function as an electrically controlled switch that is an insulator that operates with line voltage. When the voltage that the arrester experiences is above the voltage that is used to reference the device the MOV blocks enter into conduction. Because the MOV blocks are non-linear, if they drop below reference voltage, conduction stops.
Why do arresters operate?
A surge arrester has to be able to stand up to the continuous power frequency voltage the purpose for which it was designed to function. It should eliminate any temporary electrical energy that is generated by the equipment as current, while also preventing the voltage that is applied to the equipment from becoming too high. It must function within the same setting as the safeguarded equipment. The Temporary Overvoltage (TOV) capability indicates the amount of overvoltage that is permissible and the duration that an arrester is able to withstand without causing damage.
Arresters are able to operate for various motives:
ToV condition lasted way too long
Affixer that is too small
The lightning surges experienced were more than the duty rating.
Gap degradation in silicone carbide arresters
The deterioration of the housing made of oil because of the leakage in the additive silicone oil
Wildlife
Disk aging
Porcelain arresters can break up when they experience an event that is end-of-life and polymer arresters could suffer a blow to either side or a disconnector may operate to disconnect the arrester from the ground.
