Solar PV Ground Fault Detector
How to find PV insulation (Riso) faults using the Z200 PV Analyzer
Z200 PV Analyzer Ground Fault test mode
Solar ground fault troubleshooting
Solar ground faults result in PV array shutdown and energy losses. Safety hazards to service technicians is also important to consider. Using the Z200 PV Analyzer solar ground faults can very quickly and safely be located and repaired.
The Z200 PV Analyzer is a new type of solar PV testing instrument capable of measuring the position of solar PV installation electrical faults. In particular the Z200 PV Analyzer is probably the fastest solution on the market for PV ground fault troubleshooting.
PV system ground faults occur if the insulation resistance RISO drops below a certain value of typically 3 MΩ. When this happens most string and central inverters immediately shut down operation, and the risk is thus massive energy losses, if an Earth Fault (or a PV ground fault) is not found and corrected. Also safety to persons and animals becomes an issue when a PV system is not isolated properly. Among many features, the Z200 PV Analyzer offers fast an automated PV Ground Fault analysis that leads to the exact localization of faults. In the illustration below we see the PV ground fault setup i.e. the instrument is connected at the system terminals, and from here the analysis is done automatically once the user has logged on to the instrument using an internet browser on a device that is set up for WiFi communication
Periodic solar panel Riso faults
In some cases solar panel earth faults are periodic, which means they are only present at certain times. Typically moisture in the morning will provoke solar system ground faults, and strings are down until the fault dries up in the sun. This makes PV ground fault troubleshooting difficult.
The Z200 PV Analyzer has a build in ground fault detector that can measure the position of a ground fault in a solar PV system. The ground fault detector furthermore has a timer function, which means that the analyzer may be used for monitoring also.
The user can simply set a time interval suitable for “catching” the ground fault, and hence let the instrument measure for an extended time period e.g. 24 hours. When the user returns to the instrument e.g. after 24 hours of monitoring, the results may be downloaded and the position of the fault can be read.
A photovoltaic array is an investment that is not subject to wear. This hypothesis might have persisted for years, however this does not make it tenable: even carefully planned and executed arrays need monitoring, an occasional inspection and, at times, repairs.
Jochen Siemer, PHOTON International 2016
The above statement from Jochen Heimer seems to be confirmed by almost anyone in the modern solar industry, who has a field-oriented responsibility. A while ago, when solar energy was still a new star in the sky, it was common to hear sales pitches describing solar energy, and how “maintenance free” it was. Nowadays, the solar industry is however more mature and also consolidated in many areas.