LAHORE: National Transmission and Despatch Company (NTDC) has completed work on the insulators of 53km-long 500kV double circuit Port Qasim transmission line with the room temperature vulcanising (RTV) ones enabling the system to feed the power distribution system without any glitches.

“Initially, there was a plan to replace insulators with RTV coated ones at the line’s 8-9km stretch, a portion considered critical due to situation near the sea and the plant. However, it was later planned to replace all insulators with RTV coated ones for better performance,” a senior NTDC official told Dawn on Monday.

The line, which originates from Port Qasim Plant and ends at Hub, connecting Jamshoro-Guddu transmission lines, faced tripping and interrupting power transmission to distribution system since long mainly due to deposition of pollutants emerging from the sea salt impact and fuel emission from the adjacent K-Electric’s oil-fired power plant.

“Insulators play an important role in transmission lines as whenever there was pollution, the insulation level decreased.

“It happens when some stick material falls on the insulators as a result of a mixture of emissions and air moisture. Therefore, the final resolution to avert tripping of the lines in such areas is to replace the normal insulators with RTV ones,” he explained.

The coating, he said, prevents the material from sticking to insulator surface. It is a preferred solution worldwide and reduces chances of tripping. Moreover, it also reduces continuous labour of washing the lines.

“Besides this, various works on removing various system constraints at 220/132kV Nowshera Grid Station, augmentation of the transformer at 220kV Quetta, 220kV twin bundled NKLP-Wapda town line and augmentation of transformers at 500kV Shikarpur and 220kV Sarfraz Nagar grids have also been completed,” he claimed.

Published in Dawn, May 14th, 2019