Smart Water Dispenser: A Safety System for Preventing Motor Dry-Run in Water Dispensing Applications

Abstract

This study presents the development and simulation of a Smart Water Dispenser using Tinkercad block-code programming to implement sensor-based safety control that prevents motor dry-run during water dispensing. The system integrates an ultrasonic sensor with threshold-based decision logic to measure water level in real time and automatically activate a lockout mechanism when the level falls below the 25 cm safety threshold. This ensures that the motor remains disabled to prevent overheating and mechanical damage.
A developmental research design was employed, and the complete system was modeled and tested in the Tinkercad simulation environment. A total of 10 structured test cases were conducted, evaluating sensor accuracy, lockout activation, LED indicators, and motor response. Results showed 100% accuracy in detecting unsafe water levels and instantaneous lockout activation (<0.1 seconds). The system consistently allowed motor operation only under safe conditions and recovered immediately once the water level returned to an acceptable range.