Water Tank Overflow Musical Alarm
Created: Apr 26, 2017
No description available.
This is a simple home automation project based on UM66 melody generator IC. The water tank overflow musical alarm is just the same as other liquid level sensor alarms, but instead of a beep sound, it produces a melody sound whenever water in the tank overflows. The UM66 IC is the one capable of producing the melody sound when it detects the presence of water overflowing, thus preventing wastage.
Initially, the transistor Q1 remains in ON state because the potential at the node between R1 and R2 in the given circuit diagram is Vcc, so its collector voltage is at Vce sat. A probe from ground is curved in the water reservoir. When the water level rises, the ground comes in contact with the base terminal of transistor Q1 changing it into OFF state so; the collector voltage rises to Vcc. The high voltage at the collector of Q1 turns ON the transistor Q2 since this high voltage is connected to the base of transistor Q2. Whenever Q2 is ON, UM66 gets the power to operate. A 3.2V Zener diode is used to regulate the high voltage from Vcc. Upon getting power, UM66 produces the melody sound. The current from UM66 IC is not sufficient to drive a speaker, hence BC 547 transistor is used as amplifier.