In utilities, generation plants or in the industry, it is common that we trust our critical high and extra-high voltage assets to the protection provided by surge arresters. Metal oxide surge arresters (MOSA) are inexpensive devices widely used in industry and it is common for them to be installed and little care is taken in their subsequent verification, at most a discharge counter is added. Performing tests on arresters offline perceived involves a lot of work, time and cost. For this, Doble Engineering has the LCM 500 that allows online measurement of the health of surge arresters by measuring the resistive leakage current accurately and reliably. The method used (B2) is considered to have high detection efficiency by IEC 60099-5 Common problems include moisture ingress, sealing defects, discharges due to surface contamination, discharges due to stress after receiving a surge, partial discharges, or simply aging. Most of these problems cannot be verified by thermography, discharge counter or fixed installation ammeters. The resistive leakage current heats the internal blocks, heating the arrester, which affects the performance and possibility of handling the discharge energy.
In no more than 15 minutes it is possible to know the status of the arrester and thus secure our installations using the LCM500, a battery-powered instrument for field usage that allows storing more than 1000 measurements and downloading them to your PC which, through software, allows not only to prepare reports but overlay data for comparison and evaluation
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