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Light Panel loading down the power supply voltage

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May 15, 2015
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when testing different circuits that have various lighting or display panels that use edgelighting causes the power supply to get loaded down because when the type of lights or lamps resistance has increased from heat or aging i'm guessing. What lights or lamps increase it's resistance from aging or years of use. The older lamps get the tungsten wire increase its resistance. I disconnected the lights or lamps from the power supply and it pulled up the power supply. The lights or lamps resistance has increase through years of use or aging, any reasons why?

Either you do not know what is "loaded down" or you never learned Ohm's Law.
1) Loaded down is overloaded. What causes a power supply to be overloaded? Its load current is too high.
2) Does Ohm's Law say that the current increases when the load resistance increases? NO! The current decreases when the load resistance increases then the power supply is not overloaded and should work fine.

Why do you think an incandescent light bulb filament increases its resistance with use? What happens to its tungsten filament when it is at 2000 degrees C in a vacuum? Why does the glass turn black inside the bulb?
The extremely hot filament evaporates some of itself and it is deposited onto the glass. Then the filament becomes thinner causing its resistance to increase and its current to decrease.

Maybe your power supply is defective of maybe somebody replaced low power light bulbs with high power light bulbs.

If the gas inside an incandescent light bulb is halogen then I think the evaporated filament gets deposited back onto the filament. Thgerefore a halogen light bulb can be brighter *hotter filament) and/or last longer.

The power supply is being pulled down i mean. The Incandescent light bulb resistance got less so there is more current which is pulling the power supply down. Why does an incandescent light bulb resistance gets less from aging or years of use?

First you said "The lights or lamps resistance has increase through years of use or aging" and asked why, but now you say "The Incandescent light bulb resistance got less".
You do not talk straight.

The filament resistance cannot become less unless it is replaced with a higher power light bulb. Maybe the power supply voltage has become increased which Ohm's Law says would produce more load current.

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