Magnetic Stirrer with Speed Advisor and Timer Based on Microcontroller

Abstract

Magnetic stirrer is a laboratory tool used to stir or mix a solution with other solutions so that the solution is homogeneous. The existing magnetic stirrers are only equipped with a mixer speed regulator using an analog control knob. Technology and science have now progressed, so in this study a microcontroller based magnetic stirrer was designed. This tool is designed with digital speed and time settings, so that it is expected that errors from reading the speed and time of mixing the samples can be expected. The results of the homogeneity of the solution were carried out with 11 types of solutions from low to high viscosity levels. Testing the solution with a low viscosity level using 100ml water with 40ml syrup. For solutions 2 and 3, namely Water 100 ml with 20 ml and 40 ml special grade syrup. For a solution of 4,5,6 and 7, namely 100 ml air with 2.5 gr, 3.5 gr, 6.5 gr, and 10 gr salt. For solutions 8, 9, 10 and 11, namely water 100 ml with sugar 2.5 gr, 3.5 gr, 6.5 gr, and 10 gr. Based on the results of the analysis that has been carried out on a solution with low viscosity, it takes 1 minute of mixing at low, medium and high speeds. For a solution with a higher viscosity it takes 5 minutes at medium and high speeds. Mixing air with salt and air with sugar takes 10 minutes at high speed.