Smart DC fan

EMI signal line filters

In almost all flats the elevators (lifts) are essential. In high rise buildings there are 2 or 3 or even more lifts. These lifts are major source of electrical energy consumption. Why?

The lifts remain idle for most of the time and it is used during peak hours only like in morning from 6 am to 10 am and in evening from 5 pm to 9 pm. So out of 24 hours a lift is used mostly for 8 – 10 hours. Now the problem is, in a lift there is always a fan and a light that stays on continuously. Even if lift is not in used for longer period of time. Although the ON/OFF switches for fan and light are already given, no body turns it OFF. So the fan and light inside the lift stays ON continuously and makes complete waste of electrical energy. Such a waste of valuable electrical energy in this era is not at all desirable. Today all most all the countries are putting their strong efforts to save maximum electrical energy by all means. In India there is heavy scarcity of conventional energy sources from which electricity is produce. So saving electricity and thus these conventional energy sources is must.

On this thought an idea came into my mind that why not to add a kind of intelligence in lift fan and light so that it remains ON till there is atleast one person in the lift. And when lift is totally empty fan as well as light automatically turns off. So there should be a kind of sensor in the lift that senses person presence and automatically turns ON or OFF light and fan inside it.

So here i am presenting a simple circuit called smart DC fan that senses any person near by and turns on. when there is no any person it turns off automatically. Later on I have given one more circuit that is with a small change in the same circuit so that it can switch on and off 230 V AC light and fan at a time inside lift.