Device ISOP M – mechanical indicator

The beginnings of the RAM-1 device date back to 2014. As a manufacturer of surge arresters, the problem of efficiently determining the condition of surge arresters in the electrical distribution and transmission networks is well known to us. Therefore we decided to develop a device that immediately indicates the degradation of the built-in arrester in a mechanical fashion by changing the color of the display. The device was called ISOP. The mechanical state indicator ISOP for MV metal-oxide surge arresters is used to monitor the functionality of the installed surge arresters in the distribution and transmission networks. Surge arresters in the distribution and transmission networks are used as protection of electrical equipment against discharges caused by direct lightning strikes and switching manipulations. Over time, due to the greater number of events/discharges during protective operation, the functional properties of surge arresters deteriorate. This is reflected in increased leakage current losses through the arrester, which in turn causes overheating. In the worst scenario, the surge arrester can encounter a thermal runaway, leading to the destruction of the surge arrester, which in turn no longer performs the protective functions for which it was intended.

Monitoring the condition of the surge arresters is often difficult due to the following factors:

• large number of built-in elements,
• remote installation location,
• the defect is usually not visible to the naked eye (the damage of the defect does not show on the outside),
• complex condition assessment (dismantling required for measurements),
• expensive procedure.

The ISOP M product was developed, but was not accepted by the market, due to it’s mechanical functions and because each device would have to be checked individually to see if it has been done it’s job.