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View Full Version : FYI please read GE LED's sold at lowes



Pwmcguire
12-14-2009, 09:48 PM
I have posted some issues that I have had about GE LED's Sold at Lowe's.

http://doityourselfchristmas.com/forums/showthread.php?t=9695

http://doityourselfchristmas.com/forums/showthread.php?t=9111

I Haven't really gotten any response. There must not be too many people using them.

I went outside tonight to see if my display is OK and all of my c7 LED light strings on my windows are not working (I say all, but I only have 4 windows) . I use them on my windows because the length fits. The same brand c9 lights have been working fine. There is a few electronic components in the plug an in the other end that you plug in to. I have noticed that a small resistor is fried and the majority of the LED's are fried

My suggestion is to stay away from these lights.


They are left over from my static display and this is their second year
but they were a chunk of change to buy.

I wanted to put this out there because of the sales at the end of the year. I thought people might pick them up. :(:(:(

ukewarrior
12-15-2009, 12:38 AM
Can you post some pictures of the electronics package?

Pwmcguire
12-15-2009, 07:00 AM
Can you post some pictures of the electronics package?

Right now my priority is getting my window lights back on. It might be this weekend before I can post some pics, but I will. Like I said the c9's seem to be ok, they do have a heavier resistor in them. Maybe it will just take longer for them to blow.

David_AVD
12-15-2009, 07:10 AM
What voltage are they?

tonypgst
12-15-2009, 10:33 AM
My suggestion is to build your own full wave bridge rectifiers and save the strings for your use as best as you can.

The 36 strings of C7 25 count LEDs outlining my roof are all running new rectifiers that I put into place as a result of the bad strings from the 2008 CDI order. It may not be a quick fix, but with the correct parts (depending on number of LEDs, voltage drop, current, etc.), it is about a 5 minute fix per string. I was also able to put together custom string lengths (varying LED #s) to fit the outline of my roof by adjusting the resistor values in the circuit as required.

Just takes time, minimal investment in components, and a few calculations and you can salvage the LEDS. A plus is that you will have minimal problems moving forward, can fix any LED string where there is a rectifier failure in the future, and will have smooth diming as a result. As long as my strings wiring stays intact, I can replace any burnt LED bulb or rectifier issues on my strings. I consider the spare parts I may need a small investment to keeping my show running.

This year, I have had 3 failures for my roof lights. One was failed resistor, another a failed diode, and the third a bad LED. It takes less time to test and replace the components in the rectifier than it does to find the bad LED. All in all, about 15 minutes to pull the string, repair, and replace on the roof.

Note: I assume the rectifiers are the problem from your description. If you have bad LED issues, then I hope you have replaceable spares and time to check each one in the string.

I'll have to throw together a quick how-to in the future. Another side note, dont' throw away bad LED strings, ship them to me if you are so inclined. :)

Pwmcguire
12-15-2009, 08:57 PM
These are 110 volt strings sold or made by GE and sold at lowes home improvement

Here is a picture of the c7 plugs. There is a 100 ohm resistor burned at the female and 95 % of the LEDs were blown out as well, there are 26 multi color LED's in this assembly

The next picture is C9 plugs of the same maker. The resistor is considerably larger. This was from a good string. This is from a 50 multicolor led assembly
I have had no failure of these strings.

The strings tha failed were on a either a Renard 16 xmus board or a Renard 24 v3.0

I also have 1 C7 string working on a renard ss24 that dims great and has not failed.

Will they all fail eventually? I will be the first to know.

David_AVD
12-15-2009, 10:16 PM
So these strings are normally just plugged into 110V and stay on?

I'm guessing that the circuitry in the plugs doesn't take kindly to dimming.

Light strings that run directly from the mains (240V) are rare in Australia. In fact I've only ever seen them for indoor use. Almost all Christmas lights over here are 24Vac with a plug pack (wall wart), apart from most of the cheap rope light which is 240Vac.

A Marchini
12-15-2009, 10:25 PM
These are 110 volt strings sold or made by GE and sold at lowes home improvement

Here is a picture of the c7 plugs. There is a 100 ohm resistor burned at the female and 95 % of the LEDs were blown out as well, there are 26 multi color LED's in this assembly

The next picture is C9 plugs of the same maker. The resistor is considerably larger. This was from a good string. This is from a 50 multicolor led assembly
I have had no failure of these strings.

The strings tha failed were on a either a Renard 16 xmus board or a Renard 24 v3.0

I also have 1 C7 string working on a renard ss24 that dims great and has not failed.

Will they all fail eventually? I will be the first to know.'

Certainly looks like , in the failed picture, a larger resistor was supposed to go there. I be a nice 1 watt jobby would make it last a little longer. (flame proof , of course) Thanks for the inside pic,I never really new about how they function.

Tony M.

P. Short
12-20-2009, 11:05 PM
Looks like a voltage-doubler circuit similar to those in the 2008 CDI strings. As noted above, they don't seem to be designed for dimming applications (if that is what you are doing).

Also, I suspect that the vendors and circuits are different every year, that they just shoot for the strings that can be delivered in the desired quantities with the lowest price.

Pwmcguire
12-20-2009, 11:18 PM
Thanks for your input Phil

I have them dimming now. I Guess I'll modify them in the summer, if they survive. The c9's are holding up well, all but One C7 on a Renard ss24 has been working and dimming flawlessly. I had 6 other C7's die in a week on the previous versions of Renard boards, like I said they are left over from my static display. I'm planning on buying some in the CDI presale.

Pwmcguire
12-20-2009, 11:19 PM
Looks like a voltage-doubler circuit similar to those in the 2008 CDI strings. As noted above, they don't seem to be designed for dimming applications (if that is what you are doing).

Also, I suspect that the vendors and circuits are different every year, that they just shoot for the strings that can be delivered in the desired quantities with the lowest price.

How does a voltage-doubler circuit work?

P. Short
12-20-2009, 11:33 PM
http://en.wikipedia.org/wiki/Voltage_doubler

Without going into too much detail, it uses four diodes and two capacitors to get up to 340VDC peak from the 170V peak-to-peak of ordinary AC. They have put two diodes and one cap at each end of the string, along with a resistor at each end for filtering and limiting the current/power going to the LEDs.

Pwmcguire
12-20-2009, 11:36 PM
http://en.wikipedia.org/wiki/Voltage_doubler

Without going into too much detail, it uses four diodes and two capacitors to get up to 340VDC peak from the 170V peak-to-peak of ordinary AC. They have put two diodes and one cap at each end of the string, along with a resistor at each end for filtering and limiting the current/power going to the LEDs.

I can understand that. It will help me to modify the strings.

P. Short
12-20-2009, 11:47 PM
Before modifying anything you should draw out a schematic of the string to make sure that what I said is true for those strings. Who knows what they do overseas in the factories.

Pwmcguire
12-20-2009, 11:58 PM
I was looking at one today. I'm still trying to figure out the scematic. It has 3 wires coming out of the plug two that travel the whole way though to the other end. One wire through each led. It seems to have an extra wire running between every other led. I'm thinking they are in parallel because when 1 goes out the rest stay on. Maybe you could point me in the right direction.

P. Short
12-21-2009, 12:44 AM
I doubt that they are in parallel. If an LED fails by shorting out, I would expect that the string as a whole would keep working. What happens if you actually remove an LED, does the string stay lit?

Pwmcguire
12-21-2009, 12:47 AM
They stay lit, They are a nice quallity led.

P. Short
12-21-2009, 12:55 AM
Interesting. OK, they could be in parallel pair-wise. If that was the case, removing one LED might make one other LED glow brighter than the others.

Pwmcguire
12-21-2009, 01:06 AM
I have a cheap walmart set that is in series, when you pull one out they all go out.