What is the function of the diodes in a photovoltaic installation?
Diodes are electronic components that allow the flux of current in one direction only. In photovoltaic systems they are generally used in two ways: as blocking diodes and as bypass diodes. Diode connection diagrams Blocking diodes avoid the discharge of the battery through the photovoltaic modules when there is no sun light. They also avoid the current flow becoming inverted between the different parts of a parallel connected array, when in one or more of them a shadow is produced. Bypass diodes individually protect each module from possible damages caused by partial shadows. They should be used when the modules are connected in series but are generally not necessary in systems operating at voltages lower than 24 Volts. While blocking diodes avoid the flow of current from a group of serially connected modules through another group connected in parallel to the first one, bypass diodes avoid each module individually dissipating current arising from others connected in series, if a shadow
