The HPM Weatherproof Photo Electric Switch has a light sensitivie controller which will automatically turn the light on at dusk and off at daybreak, assisting in increasing security and also reducing elecricity charges. It has a time delay circuit so that it is not affected by a sudden or brief change in light level caused by intermittent cloud cover, reflections, vehicular lights or lighting. It is suitable for control switching of incandescent or fluorescent lamps.