The 500 kV power plant “Kartli-1” connects substations: “Ksani-500” and “Gardabani-500”. The length of the power transmission line is 91 km and includes 249 masts. The power transmission line was put into operation in 1968 and the АС400/51 cable is installed on it. The design load of the power plant is 900 MW.

One of the necessary conditions for maintaining the power transmission lines in a technically correct condition, as well as for the safety and sanitary standards of the service personnel and the population living along the lines, is the presence of the minimum allowable gauge between the wires of the line and the ground.

For a power transmission line of the same voltage, the distance between the wires and the ground is one of the determining conditions of the electric field tension, and it increases with the reduction of the gauge.

Restoring the gauges is mainly done by cutting the ground under the power line, or if it is possible – by stretching the wires. Nevertheless, there are cases when it becomes impossible to bring the dimensions within the norm with such methods.

For example: between the N208-N209 towers of the 500 kV power plant “Kartli-1” in Mali, the gauge wire from the Aragvi river and the Saguramo-Natakhtari water pipeline separation dam, on which the road was also arranged, was 5 meters, instead of 9 meters stipulated by the norm. The road on the dam was blocked and traffic was prohibited. A similar situation existed on the Gombori section of the Tbilisi-Telavi highway. Where the wires N98-N99 of “Kartli-1” cross the highway, the distance from the wires to the surface of the road was 7 meters, which is a gross violation of the design norm for crossing highways. Presumably, during the rehabilitation of the Gombori road at this place, the level of the road surface was raised compared to the previous one. In order to correct the situation, the design organization “Energoxelprojekti” developed a project that provided for the addition of one corner and one intermediate mast to the above-mentioned two poles, which was implemented in 2013, thereby eliminating the existing problem.

In 2018, a 10-kilometer long АС400/51 type damaged cable was replaced on the “Kartli”-1, on which a large number of repair clamps and bandages were installed. We considered the execution of the mentioned work as a priority, because during the summer period of 2014 and 2015, a wire pulled out from the similar repair clamps at the 500 kV power plant “Imeret” during the 700 MW load, which caused the emergency shutdown of the power transmission line.

Porcelain insulators were completely replaced with glass insulators (up to 15 thousand pieces) on the 500 kV power plant “Kartli-1”. In addition to the porcelain insulators, heavily soiled insulators were also replaced, which in certain meteorological conditions become the cause of the emergency shutdown of the conductive and power transmission lines. The 500 kV power line “Kartli-1” and the 330 kV power line “Gardabani” pass through the areas of Marneuli and Gardabani municipalities with heavy industrial and field pollution (thermal power plants, metallurgical plants, cement plants, agricultural fields, etc.) and dirt from the insulators of the mentioned lines S It cannot be removed by any chemical or mechanical means.