This is a Simple high water level alarm circuit diagram which we need to build it since:
Outdoor fish pond The water level will drop rapidly.
We need to check the water level regularly. The water had to be done very carefully. Should not be too hard to turn the tide The fish had Popper. When opening lightly water it needs to wait for the water to acceptable levels. Which very often my wife. Accidentally open water overdue. I think this project To high water level warning limit.
We use this idea for make : Soil moisture detector circuits and automatic controller
The working principle.
From circuit diagram Figure 1. Meanwhile, a sensor does not touch water. Though we will slide a S1-switch together and electrical current in to this circuit.
But a BZ1-buzzer also can not emit sound, since Q1-transistor also not working which the controller section is not connecting together. So not current flow through R1 to B lead (base) of Q1, cause collector and emitter of Q1 acts as switch on-off BZ1. Now current flow to stop at the collector of Q1 so cause current, not a full circuit, the BZ1 can not emit see Figure 2.
Then the level water to the sensor point cause current can flow through to R1 to B of Q1. So cause C lead and E lead as switch connecting. The current so can flow to BZ1-buzzer and C-E lead of Q1,thus current full circuit the buzzer emit we hear them on.
Then if we want to stop working of circuit is easy with turn off S1 or the level of water lower than the sensor point.
The LED display is used to indicate working of circuit as power on. It is working at all time that we turn on S1. While R1 will control a neat LED1 current.
The components list.
Q1: BC337, 0.8A 45V NPN transistor
C1: 100uF 25V, Electrolytic capacitor
R1: 47K or 50K, 0.25watts resistors
The wiring, Perforated board,
How to build its and testing.
This project is very simple so can assemble on the perforated board.
Then I test this projects as video below.
Now my wife happy it and No worry about water overflowing again.
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