Funny Acting LED Bulb

[Little Bill]

I have an LED bulb over basement stairs. It recently started acting funny. At first I thought it just failed or was failing as I've had a couple die out before. This one just had a faint glow when turned on. It stayed that way for a day or so as I kept forgetting to change it. Then one day I turned it on and it came on full bright. It worked for a day or two then went back to the faint glow.

Now, as an experiment, I'm leaving it in. When it goes to the faint glow it's always when you turn it on and never while it is burning full bright. When it goes to the faint glow it will stay that way for a couple of days then will come on full when turned on. Also, it never goes to full bright when it's on and in the "faint glowing" state, only when first turned on.

Any ideas what's going on with this bulb? I know it needs replacing just trying to figure out why it works sometimes and not others.

 

[SceneryDriver]

I have an LED bulb over basement stairs. It recently started acting funny. At first I thought it just failed or was failing as I've had a couple die out before. This one just had a faint glow when turned on. It stayed that way for a day or so as I kept forgetting to change it. Then one day I turned it on and it came on full bright. It worked for a day or two then went back to the faint glow.

Now, as an experiment, I'm leaving it in. When it goes to the faint glow it's always when you turn it on and never while it is burning full bright. When it goes to the faint glow it will stay that way for a couple of days then will come on full when turned on. Also, it never goes to full bright when it's on and in the "faint glowing" state, only when first turned on.

Any ideas what's going on with this bulb? I know it needs replacing just trying to figure out why it works sometimes and not others.

My guess is a cold solder joint or bad component that is moving with changes in temperature. It's causing the circuit's resistance to alternate between high and low. That's only a guess; LED bulbs are commodity items these days and aren't exactly bespoke, hand assembled items. Mass produced items like this sometimes have QC issues. I'd take it out of service ASAP. Bad connections can lead to things melting and letting the magic smoke out. If you pull it apart, you may be able to see the bad connection or component.



SceneryDriver

 

[JFletcher]

At the very least I'd replace it to make sure the problem isnt on the electrical/power side.

 

[RumRunner]

These LEDs have a lot to be desired. One LED even of the same make or lumens are not exactly identical in terms of quality.
Did you ever notice that most of them are not even labeled? I guess the manufacturer doesn't want to get bothered by failure complaints.

I use and bought a large number of these babies to determine which ones are better than others. They don't cost much so I can afford a whole bunch without breaking the bank.

So now I got a bucket full of them. I use them in both my RV and in the house.
I did find out that if it is marked for 120 volt I use a drop down resistor. For 120 v, I use a 22 K ohm half watt. For higher lumens I use lower resistance value 5k ohms works good. . . .no overheating which is mostly the cause of failures.

As for my RV, I use a 68 ohm half watt resistor. They are mostly identical in terms of light output so no need for changing resistance value for each particular fixture.

The reason for failures are, when the RV is plugged in to shore power or the engine is running, the voltage output at the battery terminal reads (by design) at 13 to 14 volts DC. This higher (over 12 v) is enough to kill these LEDs.

The resistors did work fantastic in both house and RV. Never had a single failure for almost two years now. Before the resistors, they only lasted about three to four months.

The jury is still out but I'm keeping my fingers crossed.

 

[Little Bill]

The ones that I have in my house are mostly for experimental purposes. I get asked alot about what type/kind of LED bulbs are good. I want to be able to give that info out from experience. I try to buy name brand so that I know I can get replacements easy.