In this post I have explained a simple configuration which can be used as a automatic changeover circuit for switching AC grid mains to generator mains, during power failures or outages. The explained circuit will effectively switch the connected appliances to the generator mains during power failure however it won’t be able to switch start the generator automatically, […]
Mains
Arduino Mains Failure Battery Backup Circuit
In this article I have explained a simple mains failure backup circuit for providing Arduino boards an uninterruptible supply during such situations. The idea was requested by Mr. Fredrik. Technical Specifications This blog gave me a lot of interesting information. Especially the power supply circuit with battery backup part. The reason for this is that […]
LCD 220V Mains Timer Circuit – Plug and Play Timer
In this post we are going to make an LCD 220 V mains operated timer using Arduino whose countdown time can be witnessed via 16 x 2 LCD display. Introduction The proposed LCD timer circuit is general purpose timer with display and few buttons for setting the time. Once the time is set output goes […]
Password Controlled AC Mains ON/OFF Switch
In this post I will show how to construct a password based mains ON/OFF switch circuit, which can turn ON and OFF the AC mains supply, only when correct password is entered. This prevents the danger of electrocution of the technician who might be currently working with the high voltage lines and equipment. Password Protection […]
Mains AC Short Circuit Breaker/Protector – Electronic MCB Circuit
In this post I will try to explain the making of a simple 220 V, 120 V AC mains short circuit breaker using an SCR and a triac combination, (researched and designed by me). The circuit is an electronic version of the normal main circuit breaker MCB units that we use in our homes. Note: […]
2 Easy Automatic Inverter/Mains AC Changeover Circuits
I have been put forth with this question many times in this blog, how do we add a changeover selector switch for automatically toggling of an inverter when AC mains is present and vice versa. And also the system must enable automatic switching of the battery charger such that when AC mains is present the […]





