I-V Curve Tracer for maintenance and troubleshooting of photovoltaic systems. Measurement of I-V Curve of one or more modules or of one whole string up to 1500V/10A. Measurement of open-circuit voltage and short-circuit current Voc/Isc. Database of 30.000 selectable photovoltaic modules I-V500w allows field detection of I-V Curve an of the main characteristic parameters both of a single module and of strings of modules for PV installations up to a maximum of 1500V and 10A or 1000V and 15A.