Suchita P. Bhangale
An embedded system based colorimeter has been developed for the analysis of copper in waste water. The design is based on the ARM-7 LPC-2148 processor. The data convertor section of the processor is interfaced to the photoelectric sensor of the colorimeter. The inbuilt DAC is used for the control of intensity of incident light produced by light source. The monochromatic colored LEDs are used as source of stable light. Similarly the inbuilt ADC is used to measure the potential corresponding to the transmitted light. The transmitted light is detected and converted into potential by the LDR circuit. The instrumental and the experimental errors introduced due to the absorption by cuvette and the reagent respectively were compensated by the software techniques. In addition to above functions, the software performs the operations of calculation of absorptivity coefficient, detection and estimation of concentration of copper. The developed equipment has been successfully used for the analysis of copper in waste water. The software program can be easily modified for the similar study of other analytes.