Auto-light controller

摘要

The holiday season is with us again. It's a time to go away for rest and relaxation. So you do everything you can to secure your property, including leaving a light on. But, unfortunately, nothing is going to stop a determined burglar from breaking in. So here's a better thing to try as a deterrent - an auto-light controller. This little invention will turn your selected lamp on and off in a manner which will appear to be random, although, in fact, the light will turn on for about 44 minutes, then off for the same period and so on. It will track how overcast or bright the evening is and not start these cycles until it is beginning to get dark and then around about midnight, it will switch off completely, not to switch on again until twilight the following evening. Its use can make apparent occupation look very authentic. The controller is made from inexpensive components, uses a standard mains socket and matching wall box and is easy to construct. In addition to it being used to switch lamps on and off, it can also control other small mains loads, including fans. It is limited to a maximum supply current of 3A.