Solar cell inspection machine

The shuntometer is a simple low cost set-up to determine the location of short-circuits (shunts). It allows a quick identification of material or processing problems and helps to prevent hot-spots which can occur when at the module level. The manual system can detect all major shunts in large area reverse biased solar cells. It therefore allows the imaging of large numbers of cells in a short time. The system is based on the use of commercial liquid crystal sheets which are brought into thermal contact with the solar cell by vacuum. The colour change of the sheet is an indication of the local heating of the cell at shunt locations under reverse bias at typical voltages between -2 and -10 V.