Full tank Alarm

This is one of my latest projects using  Snap Circuits Pro.

This is a simple circuit which sets off an alarm when it detects a full tank. (In this case, a basin full of water.)

Components used:

• AA Ni-Cd batteries, 1.2 volts, 1000  mA rechargeable. (4)
• Speaker
• Alarm IC
• NPN transistor
• 100Ω resistor
• 1 snap connector (1)
• 2 snap connectors (6)
• 3 snap connectors (3)
• 4 snap connectors (2)
• 5 snap connectors (1)
• Jumper wires (2)

Assembly of parts was done as shown here.

The two jumper wires act as electrodes and are placed at a level in the tank, beyond which no more water can be filled. The alarm is set off when the water reaches the level of the electrodes, which is also the tank’s maximum capacity.

The finished model: