DEVELOPMENT AND TESTING OF A MASS, TEMPERATURE, AND RELATIVE HUMIDITY (MTRH) DATA LOGGER FOR DRYING EXPERIMENT

Abstract

Temperature monitoring is crucial across various industrial and experimental applications, and processes. In an attempt to solve the problems of data collection during drying experiments, a mass, temperature and relative humidity data logger (MTRH data logger) was developed using Arduino micro controller that was integrated with two DYMH-103 Load cell and four DHT-11 digital temperature and relative humidity sensor for the measurement of mass, temperature and relative humidity during agricultural products drying experiments. The data logger was being powered by a 12 volts DC source and capable of recording its readings every 5 minutes in an embedded 16 GB SD card. The readings can also be observed from the 16 by 2 LCD display in the logger. The developed data logger was used simultaneously for same sample and environment assessment with other standard laboratory measuring instruments for calibration. The data logger was tested and calibrated in relative to other standard measuring instruments. A laboratory weighing balance SCALETECH SAB220 whose accuracy was 0.0001 gram was used to calibrate the mass measurement values. The temperature reading of the instrument was also compared and calibrated in relative to the readings of Applent AT4208 Multi Channel temperature meter of accuracy of 0.2%+1°C and the relative humidity readings compared and calibrated in relative to readings obtained using UNI T industrial hygrometer Model UT331 whose operating humidity ranges from 0%RH to 100%RH. The mathematical correlation between the readings of the developed instrument and the standard instrument was graphically obtained for all the different measuring components.  The coefficient of determination for each correlation was also obtained to range between 0.9682 and 0.9994. The developed data logger offers a cost-effective solution with specific features that suites    the requirements of a greenhouse drying experiment.

KEYWORDS: MTRH data logger, Temperature, Relative humidity, Mass  Measurement, Greenhouse dryer.