SCHEMATICS FOR CIRCUIT BOARDS

Ranking of photovoltaic panel circuit manufacturers
What are the world’s seven largest solar manufacturers?1. Tongwei Solar (TW-Solar) Tongwei Solar (TW-Solar), a subsidiary of the Chinese Tongwei Group, sits at the top of the list as the largest solar panel manufacturer in the world. . 2. JA Solar . 3. AIKO . 4. LONGi . 5. JinkoSolar . 6. Canadian Solar . [pdf]
Measure the open circuit voltage of the photovoltaic panel
Read the voltage on your multimeter and compare it to the open circuit voltage (Voc) listed on the back of your panel. If your voltage reading is negative, reverse the probes and measure again. [pdf]
Photovoltaic inverter open circuit
An open circuit fault, reflected as maximum cell's output voltage, with no ability of current to flow (hence no power output) is often caused by broken cells, damaged connections between them, loos. [pdf][FAQS about Photovoltaic inverter open circuit]

Causes of interphase short circuit in photovoltaic inverter
Short-circuiting often occurs when a variety of factors combine, such as:Moisture and damage to the cable insulationImproper installationInadequate connection of DC cables to the panelMoisture affecting the PV module connections [pdf]