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Portuguese Inspection indicates replacement of 20 insulator chains due to corona effect
During 11 days, COTESA Engineering carried out the inspection with an ultraviolet camera and detected the need to replace 20 insulator chains due to the corona effect in a total of 252 structures. In one tower it was also recommended the general cleaning of the conductor cable to assess the possible need for replacement.
In addition to the failures in the insulator chains, abnormal corona effects were identified in all the clamps of the conductor cables of the auxiliary chains (jumper) of the anchorage type towers. Thus, it is recommended to check and/or retighten all the bolts, as there may have been some looseness in the bolts due to the time the transmission line has been in operation.
The corona camera is an innovative, state-of-the-art ultraviolet imaging system that targets, detects, and records photons from corona effect, electric arc, and partial discharges. With high-sensitivity devices, it is a powerful tool for detecting UV (ultraviolet) emission in broad daylight with low intensity emitting sources, both at long distances and at close range.