Anyone have a light fixture that just burns out bulbs faster even though the wiring is fine? I have an incandescent one in my basement that burns bulbs out 2 to 1 faster than any other ones on the same circuit. What gives?
Or know why fluorescent bulbs seem to last longer if they are left on all the time?
I have always been told not to put fluorescent fixtures and incandescent fixtures on the same wiring leg. “They” told me that the incandes. light will burn out. But nobody ever told me why this is. Anyone, Anyone?………………….
Also, I am interested in any homebuilding myths, superstitions. There was a thread on the old board close to this, but I lost track of it around the time of the “great board change of 2002”
Ghosts? Secret electricity Gnomes? funny stories, snide remarks? Maybe like the gnomes that steal my keys when I’m running late.
Replies
The incandescent. After tracking a few of these down and lacking any more authoritative information I have found that heat build up is the problem. Heat damages the seals of the light bulb. The surest solution is to replace the fixture.
Sometimes a careful examination will reveal the specific problem with the fixture. Loose rivets or screws making the electrical connections will cause this problem. A center tab pushed too far down or a corroded or damaged shell will prevent the bulb from screwing in far enough to make the connection. Pulling the tab up or lubricating threads of the bulb with graphite, a carpenters pencil applied firmly and liberally to the bulb threads, will sometimes correct the problem.
Aluminum shells are particularly prone to these problems. I have had the shell on a new fixture to bind and gall with a new bulb. This leaves you a fixture that is difficult to get bulbs into and not uncommonly out of. Bulbs breaking while leaving base in the socket is a probable outcome. When buying a fixture look for sockets with chromed steel or brass shells, anything but soft aluminum. These are less likely to bind.
Just because the bulb lights up does not mean you have a good connection. One way to check is to run the light for 10 minutes or so and to feel how hot the socket is. Try this with a lamp without this problem. Usually the socket will be hot but not too hot to keep your hand on. Compare this to the basement socket/s. If it is running hot you likely have your problem.
All this assumes no great wiring faults. These would likely show up as other problems unlikely but something to watch for. Also look for any source of water dripping on the bulb. Basements are notorious for humidity and condensation on a cool surface dripping down could be enough to blow the bulb. Your best bet is to replace the fixture.
The dynamic you noticed, most people are not this perceptive, with the florescent bulbs burning out has to do with the construction and operation of the fixtures. When you turn on the light activates several heating coils to vaporize the Mercury and other materials contained in the florescent tube. The chemicals are in the tube to allow the ballast to throw an arc the length of the tube. This arc radiates UV radiation that is converted by the phosphor powder coating the inside of the tube to visible light.
The problem is that every time the lamp is lit some of the mercury and other chemicals don't vaporize and instead condense on the inside of the tube. These are the grey rings that appear in florescent tubes. With many starts, made worse by cold temperatures, these rings get darker and wider. Eventually there are not enough of these chemicals available to allow the arc to form.
When this happens the lamp will light only after many tries or not at all. If the fixture is left on with the bulb worn out it can cause the ballast to continually try to start. This will likely cause the ballast to overheat or be damaged. When the dark rings appear and the fixture no longer lights consistently it is best to replace the tube promptly. Ballasts are frequently as expensive as an entire fixture.
All this makes most florescent fixtures, despite their efficiency, a poor choice for a light that will be turned off and on frequently. In the early 70s some department stores would run their lights 24/7 because the lamps, bulbs, were more expensive to replace than to run. By not turning them off and on they extended the life of the bulbs. Electricity was cheap.
To maximize the life of your florescent tubes when you first install them run them for several hours before turning them off the first time. This allows the tubes to come to operating temperature, stabilize and the chemicals to disperse throughout the tube. Frequently these chemicals are concentrated at one end, starving the other end, because of the way they are stored.
4- thanks for the insight on the florescent lighting. That bit of data helps my understanding immensely. now I know the cause of ballast trouble and will be able to fine tune the lights at work.
I HAVE A LIGHT THAT TURNS ON AND OFF BY ITSELF ??????????? THERMAL PROTECTOR???
if it's a flourescent w/classP ballast, replace it -- fire hazard if the TP fails next
"I have always been told not to put fluorescent fixtures and incandescent fixtures on the same wiring leg. "They" told me that the incandes. light will burn out. But nobody ever told me why this is. Anyone, Anyone?..............."
BULL S###!! Plain and simple.
4LORN has fairly well detailed the other answers. But I will add another one to the early burn out bulb. Vibration. Mostly likely found on garage door openers. But I have also heard of problems with sidewall outside lights where people are always slaming the door and basement ceiling fixtures on "boucny" floors.
If I remember correctly the life specs that are given for fluorescent fixtures and incandescent fixtures bulbs are based on minimum on times of 3 hours for each cycle. Also they will last much longer with electronic ballast and short on cycles.