Multifunctional device for commissioning tests of photovoltaic systems. Automatic sequential testing: Insulation measurement up to 1000 V DC. Open-circuit voltage (Voc) and short-circuit current (Isc) measurement up to 1000 V/15 A. Continuity testing of protective conductor at 200 mA. PVCHECKs allows quick and safe testing of electrical safety for PV systems (DC section) and functional testing of modules/strings according to IEC/EN62446. During safety testing, it can measure module, string, or entire PV field insulation without external short-circuit disconnects. It also verifies connections and strings in the PV field per IEC/EN62446 by measuring open-circuit voltage and short-circuit current in operational (OPC) and standard test conditions (STC) with additional accessories SOLAR-02 and HT304k, providing immediate results. Finally, it enables analysis of PV field performance (DC) under operational conditions (connected to inverter) using additional accessories SOLAR-02 and HT304k, providing data on generated power and efficiency.