The extension of cable lines in the electric power system also increases the need to ensure their reliability. This can be enhanced by monitoring of characteristic parameters which are directly correlated with the condition of the cable system insulation. However, the long-term reliability of the cable network depends decisively on both the cable and its pertaining accessories. There is an important difference between cables and accessories concerning the manufacturing process. Cables are made in factories under closely controlled conditions, whereas accessories must be assembled on site. It is also essential that testing and measurements of a cable line are made immediately after laying, which allows for obtaining of data on the characteristic parameters representing the initial or zero state. The paper will discuss challenges regarding field testing of high voltage 110 kV cables using ACRF system and other testing equipment for executing on-site commissioning tests where the main purpose was finding of irregularities, weak points and how to increase the quality of test results.