By MARK DEVOLDER
Los Alamos
When a house burns down and the exact cause cannot be determined, it is usually attributed to an electrical problem. There are a variety of older and newer homes in Los Alamos County, which are provided with lighting fixtures and lamps of various types. For example, some fixtures or lamps utilize 110-volt bulbs, and some fixtures or lamps utilize light-emitting diodes (LEDs). With age and use, lighting fixtures and lamps can present some electrical safety problems.
Some time ago, I was changing out a bulb in a lighting fixture. I happened to look at the base of the 110-volt light socket and noticed that the prong at the base of the socket had turned black. This typically occurs if the prong at the base of the socket has been bent downward with use. A bent prong can result in arcing between the prong and the base of the light bulb. Arcing between the prong and the bulb may also cause additional arcing in the light switch. When I see this kind of problem, I de-energize the lighting circuit at the breaker box, clean off any black deposits in the lighting fixture socket, and bend the prong up slightly.
Recently, I acquired some portable lamps. While checking the lamps, I noticed that one of the lamps activated the LEDs intermittently. A second lamp had LEDs, which flickered. A third lamp had a 110-volt bulb which flickered.
After some testing, it appeared that the problem with the lamps containing LEDs was in the switches. I assume that with age and use, there was some arcing inside the switches. I ended up spraying the switches with a small amount of WD-40 and worked the switches back and forth between the on and off positions. I noticed that the switches behaved differently (that is, made more of a clicking sound) after being lubricated. The lamps functioned normally afterwards. (Note: WD-40 is flammable. Follow the instructions on the aerosol spray can and proceed with caution. Clean off any excess WD-40 from the outside of the switch.)
The lamp with a 110-volt bulb flickered. The lamp had a bent prong and a black deposit. I ended up cleaning the prong and bending it upward. However, the flickering problem did not disappear. Once again, I applied a small amount of WD-40 on the light switch and worked the switch back and forth between the on and off positions. The lamp functioned normally afterwards.
When I worked at LANL, one of the electrical engineers asked me if I knew where he could acquire an electrical switch for an older Craftsman table saw. My suggestion to him was to rebuild the switch. I have seen switches fail on portable shop vacuums and battery-operated drills, too. With a little effort, it might be possible to save a useful appliance or piece of equipment. It might also prevent a house fire.
