There are many different methods of testing strings and PV Modules. This article is just an overview of the different methods available. IMPORTANT: While most of these tests are commonly used in array fault localization and troubleshooting, some cannot be performed with a Tigo MLPE inline (or attached) to the PV-Modules. An open circuit test can be performed to measure the open circuit voltage of the module or the string. The test requires a DC voltage meter, and it helps to detect intermittent connection issues or open sub-circuits inside the. An Earthing Tester measures the resistance of the earth/ground by employing a constant current generator which injects current into the earth between electrode spikes. A short circuit test measures the short circuit current of the module or string. Compare that current value to the expected short circuit current of the module spec sheet, given. An I-V curve tracer will test a panel from open circuit to short circuit and all points in between under load. IMPORTANT, this will give you the most accurate indication into the health and performance of the PV module. 1. Requires an I.
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