Working Principle Arrester

Protective equipment is the most complete arrester (lightning arresters; kada-sometimes also called a surge diverter). In essence this arrester consists of two elements: between fire (spark gap) and no linear prisoners or detainees valve (valve resistors), both connected in series

Upper and lower limits of the spark voltage is determined by the maximum system voltage and by the isolation level of protected equipment. Arresters actually consists of three elements: fire interrupted, prisoners or detainees faucet valves and system settings or voltage division (grading system).

As stated in advance, if the problem only protects the insulation against the danger of damage due to interference between the rod then just used that allows the spark when the voltage reaches a state of danger. In this case, the voltage alternating system will maintain the arc until the load breaker is opened. With the connect between this fire with a prisoner, then maybe the fire can be extinguished. But if the prisoner has a fixed price, then the voltage falls becomes greater, so the intention to abolish the voltage is less accomplished, and the purpose of protecting the insulation failed. Therefore use faucets prisoners, the which have specialproperties of the prisoner That minuscule voltage and largecurrent. Reduction process takes place once the prisonersQuickly During the overvoltage reaches its peakprice.Overvoltages in this case resulted in a drastic decline thanthe prisoners, so That the voltage current is limited despite the bigfall.

LA Voltage-Current Characteristics

If the maximum tension was more exhausted and live a normal voltage, current incarceration rose again so that the aftershocks are limited to approximately 50 A. Subsequent flow was finally turned off by the fire broke at the time The system voltage reaches the first zero point so that the tool acts as a valve that closes the flow; from here didapatkan name faucets prisoners. In the current arrester outages aftershocks large enough (200-300 A) is done with the help of a magnetic field. In this case, then both the amplitude and duration of follow-up current can be reduced and pemadamamannya system can be carried out before the voltage reaches zero price.

Aftershocks can be added that the current does not alwayshappen every time arresters work, depending on the presence or absence during overvoltage. This is understandable because the current apat aftershocks that just put out on the first zero currentor the previous one.

Based on its quality, known three arresters: substation (stationtype), the transmission line (line type) and distribution(distribution type) type substation kontruksinya heavier,karakteristinya better, higher current carrying capacity of its release (no more than 100 kA, 5 x 10 μs) and used to protect thesubstation and power transformers. This type of transmissionchannel is used to protect distribution transformers, transformer-powered small, and sometimes also a small substation. This type of distribution is primarily used to protect distribution transformers mounted on poles. Types trasnmisi and distributioncapacity are both made ​​to withstand 65 kA with 5 x 10 μs waveform.

In the normal voltage conditions, fire bulkhead prevents anycurrent flowing into the column. In the event of an overload, insulation fire will die and disposed of to ground pressure. 50 Hzcurrents that appear later are limited by the endurance blockvalve and the sparks that arise will be cooled at room sparks.Sparks will quickly extinguished and then be ready to protect thearrester equipment wire from the pressure of the next voltage.Blanking period is very short, rarely able to last more than afraction of a millisecond.


Arrester that allows us to reduce the BIL requirements of the devices installed at the substation. On HV and EHV systems, reducing the BIL will reduce the cost of the devices installed. picture below shows a lightning arrester installed at substation 150 kV and 500 kV.