IoT-based Environmental Monitoring System using Thermohygrometer MHB 382-SD and ESP 8266

Bandung Metrology Directorate is one of the calibration laboratories that must provide guaranteed measurement results for calibrated measuring instruments. ISO 17025 requires monitoring, control, and recording of environmental conditions according to standards. Currently, laboratory environmental monitoring is still manual, requiring additional data processing to ensure that temperature and humidity are appropriate. Therefore, an IoT system was designed to monitor environmental conditions in real-time. The data collection method involves comparing data sent from RS 232 to the dashboard, taking into account the timing. Periodic and on-change data comparison methods, variations in the providers used, and the sequence of data transmission were also conducted. The results show that the information data sent from RS 232 to the Arduino IoT Cloud dashboard can be transmitted accurately. Furthermore, data sent periodically every 1 second compared to onchange data has an average difference of 0.06 seconds. Data sent periodically is more consistent than on-change data sent only when there is a change in data. The provider also greatly affects the speed of data transmission and reception. The sequence of received data is unstable and inconsistent, but this is not significantly apparent in the dashboard due to the very fast average data transmission of 0.19 seconds. Unstable internet signals or connections, IoT device failures, errors in data processing on the server or web application side can result in inconsistent data arrangement