Firstly, requirements for connecting a photovoltaic (PV) system will be overviewed. To connect a PV system to the grid, it is necessary to evaluate certain parameters. It is always necessary to calculate power flow, short circuit currents and voltage level as well as its difference from nominal grid voltage. There are also additional conditions depending on how powerful the connected energy source is. These requirements are stricter for more powerful energy generation sources. In this case study, one medium power level (450 kW) PV system’s connection to low voltage grid is analysed. Medium power level systems (0.25-4.99 MW) have more requirements. In addition to previously mentioned conditions, voltage surge, short circuit phase angles and short circuit power at the point of connection to the grid must be calculated. It is also necessary to carry out a harmonic analysis. All these calculations will be carried out using the EA-PSM program. Please keep in mind that these requirements may be different in other countries. The scheme used in this case study is provided in Figure 1 and the analysed solar farm can be found on lower left side.