We were invited by the Power Grid Corporation of India Limited to replace the 1960s KONÇAR (Yugoslavia) disconnectors installed at the Bassi Sub-Station in Rajasthan.
These disconnectors had been serving them since the last 50+ years and were practically maintenance free except for the current carrying parts which had deteriorated over time.
We designed and installed 2 such 420kV Double Break Center Rotating Disconnector Switches with Earthing Blades in the year 2015. In 2019, when asked about the performance – we jointly decided to conduct the M2 cycle test (10,000 operations) on the disconnectors.
As expected, the contact resistance and operation time were well within the range.