Model No: 209 The aim of the project is to make a low voltage and high voltage indicator. This system will save costly electrical and electronic appliances from the adverse effects of very high and very low mains voltages. The circuit features auto reset and utilizes easily available components. It makes use of the comparators available inside 555 timer ICs. Supply is tapped from different points of the power supply circuit for the display and control circuit operation to achieve reliability.
The power supply consists of a step down transformer 230/12V, which steps down the voltage to 12V AC. This is converted to DC using a Bridge rectifier. The ripples are removed using a capacitive filter and it is then regulated to +9V using a voltage regulator 7809 which is required for the operation 555 timer. For more details visit www.efxkits.com or www.facebook.com/edgefx