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A question about LOR and powering LEDs


Randy

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Richard,

Thanks for the tip! I am having issues with some channels and this should solve it.

Let me know where you got the Male/Female clamshells.

THANKS!

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wirekat wrote:

Richard, Thanks for the tip! I am having issues with some channels and this should solve it. Let me know where you got the Male/Female clamshells. THANKS!


wirekat, I was looking for the male/female clamshell adapters at Home Depot last night. I did not see any. I made these 2 years ago, but surely they should be around. I will look online today and come back to post if I find them. I originally got them at Home Depot.

Alternately, I think Randy's solution is a good one as I mentioned earlier. From the photo, it appears he used the slide-on AC plug, AC socket, and C7 socket that are readily available at many places online. They easily slide onto SPT1 wire that you can get at any hardware store. Thus, no tools needs. Is that what you did Randy?

Yea, it is a little bit more expensive, but a safe solution also. The only downside as he mentions is burning 7 watts for no reason. And if you have to do that on 16 channels, there goes 110 watts in the air. I also estimate the cost per channel is about 50 cents AC plug, 50 cents AC socket, 50 cents C7 socket, 10 cents wire, and 75 cents for the C7 bulb... so that is $2.35 per channel to correct LEDs.

Bottom line, I suggest that using any of these methods, Randy's, mine, or others is probably a good idea only if you are trying to salvage a bunch of older LED strings (like you said) that you already have. For new strings, its actually cheaper to just buy the better quality full-wave rectified LEDs that have no perceivabe flicker, and in my experienced, every string of full-wave rectified LEDs don't have a problem fading.

And keep in mind that it only takes about 1/2 to 3/4 watt of load on a channel to allow for smooth fading of LEDs, so if you can find lower wattage incandescent bulbs or use a resistor, you will waste much less energy on multiple channels.
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Spounds like a good easy solution Richard, thank you. Herein lies my problem. You mnentioned quite a few times that this is only needed for the older LEDS and not the full-wave rectified LEDs. I purchased a case each of Red, Green, Blue, and Yellow 5MM LED from Paul. I was playing with 1 string of 35 count blue and it had a severe flicked in fading. When I plugged a strand of minis to it the flicker was corrected. Could it be that it is because it was only 1 strand of 35, therefore there was not enough for the triacs? If so that just means I should plug 3, 4, or 5 end to end and see if that helps. I appreciate you helping out like this. I am not planning on using just 1 strand, so it may be that I do not need any of these.

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JimCanfield wrote:

I was playing with 1 string of 35 count blue and it had a severe flicked in fading. When I plugged a strand of minis to it the flicker was corrected. Could it be that it is because it was only 1 strand of 35, therefore there was not enough for the triacs? If so that just means I should plug 3, 4, or 5 end to end and see if that helps. I appreciate you helping out like this. I am not planning on using just 1 strand, so it may be that I do not need any of these.


Jim, I really doubt that plugging more led strings into the same channel will solve the problem. A typical led string of 35 bulbs should draw at least 5 watts, so it is not a problem that the leds draw so little current that the triacs aren't fading smoothly. It's likely the fact that they are half-wave rectified leds so when the AC current switches to power the LEDS in the direction opposite of the diodes, no current will flow during that 1/2 cycle and hence the triacs see no load.

When you plugged in the mini lights, that kept a constant small load across the circuit. This is the best and easiest solution to the problem. When I have a string of old LEDs that flicker, I sometimes add in a string of mini lights of the same color to give it a load. It depends on where I am using the LEDs. I light the lights to look all the same. Just be sure that the incandescant light are plugged into the controller first.
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Yes, I built up my adapter from SPT2 wire and vampire plugs from Action Lighting with a 5 watt C7 bulb.

I did this because of the LED Branch trees I bought at Target this year, but also because of the Full-wave CDI LEDs that I purchased this year.

On the CDI LEDs, what I've noticed from testing is that the strings of 100 of either C6 or M5 seem to fade okay. It's when I get less on one string (50 and 70 for me) that I'm having fading issues. I spent a lot of $$$ for those LEDs, and even though Paul has made the offer to take them back after the season, I have to disassemble them and pay for return shipping. I haven't decided what to do on that front....

Interestingly enough, if I do connect two strings of 50 or 70 in series, the fades look okay, or if I connect a set of 100 LEDs at the end of the 50s or 70s. So there does seem to be an issue with the minimum load for the channel.

Unfortunately, I do have several channels where I have just one string of 50 or 70 on that channel, so these adapters were a way to try and "Rectify" that. I did order some 33K resistors from a seller on eBay, so those should in soon. If I can't find a clamshell, I'll try to put together something from my extra parts bin here to prevent from having to burn 5 watts on each channel....

Thanks for your help...

Randy

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Randy, I think that the reason why you are able to solve the problem by connecting more than one string together is because they are full-wave rectified so there is a load on each 1/2 of the AC cycle. Frankly, I am surprised that just one string would have trouble.

With half-wave rectified strings, I'd be surprised if any amount of series connected strings will solve a flickering problem.

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I just built 3 of these and the channels I placed them on seem to be more under control. Fade still not as smooth as I would like it but at least the sporadic flicker has been reduced. 2 set of 70 with the resistor load sporadic flicker gone. 1 set of 70 flicker reduced.

Now to make up another 40 or so of these. :P

Just a quick question... The Clamshell used in the example. How would I go about making it water proof? Fill it with clear silicon?

Thank you for the tip! :]

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Dennis Warren wrote:

I just built 3 of these and the channels I placed them on seem to be more under control. Fade still not as smooth as I would like it but at least the sporadic flicker has been reduced. 2 set of 70 with the resistor load sporadic flicker gone.

Dennis, if the fading is not smooth, it is likely because LEDS are not as linear as incandescant bulbs. Example, some LED strings may appear fully bright at just 70% voltage and may shut off abruptly at 10%.
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Still a little confused about the "clamshell"

Does anyone have a picture of one or a website showing one.

I looked at Randy's pictures but I did not see the female end.

Maybe I am missing something. I would like to try building one but I

am not sure what to look for at the electrical dept.

Thanks

harbs

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Harbs wrote:

Still a little confused about the "clamshell". Does anyone have a picture of one or a website showing one. I looked at Randy's pictures but I did not see the female end. Maybe I am missing something. I would like to try building one but I am not sure what to look for at the electrical dept. Thanks harbs

Hello Harbs, if you are the same Harbs who is a member of my site, then you will find photos on there. Send me pm here or there and I will help explain.
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Hi Harbs,

In my original post at the top of page 1 on this thread, I included a photo of the Target box and my extender cord with the C7 bulb in the middle. On my cord, the male plug is at the top, and the female receptacle is at the bottom, with the C7 bulm in the middle....Can you see the female end in the photo?

Thanks, Randy

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Sorry for the confusion. I did see your pictures earlier this evening but in some of the discussions

I thought someone said the clamshell had to be installed between the controller and the LED string.

Your web site says you can use if at the end.

Thus you can plug it into the female plug at the end of the string.

I was trying to figure out how to use the male clamshell between the contoller and the LED string.

Thanks for your help and sharing your knowledge.

Harbs

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Jim, Harbs, and others. Let me clarify something where I may have misled you.

On most LED strings you can plug the "snubber" into the end of the LED string. Thus for the ones that I make where there is a clamshell with no female socket, they can plug into the end. This is because most LED strings will carry both legs of the AC line to the end of the string to supply for the next string.

However in two occasions, I have seen LED strings that did not carry the AC legs to the end without passing through LEDs first.... and thus the snubber (or C7 light) won't work. For any of these techniques to work, they must be connected across the line so that the controller sees the load during both reversals of the AC line. Fortunately, all of the old LEDs that I have are ok with the snubber connected at the end of the line. So bottom line is that if you plug in your snubber at the end of the LED string and it does not solve the problem, the you need to try it up front.

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Something to remember when buying clamshells to place at the end of the LED strings. The LED string ends are non polorized therefore the female and male end do not have a larger prong. So if your going to buy clamshells for the snubber make sure you get the type that are non polorize (both male spades same size)!!

Next, do they exist? Time to start look'n.. *grins

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Dennis Warren wrote:

Something to remember when buying clamshells to place at the end of the LED strings. The LED string ends are non polorized therefore the female and male end do not have a larger prong. So if your going to buy clamshells for the snubber make sure you get the type that are non polorize (both male spades same size)!!

Next, do they exist? Time to start look'n.. *grins

Great point Dennis. My strings do happen to be polarized, so I am not having that trouble, but I see that some newly purchased LED strings don't have the wide ground.
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Found something else of interest. I remembered that long extension cords also create a load in itself. Most of my testing has been with 8ft lengths of SP2 wire. After making a few Dual Channel 25ft Extensions I Pluged them in on my test wall...

Yes I have a test wall in my home office. *Grins...

And No Flicker. With 2 70ct LED strands. So you may not need the snubber for runs over 25ft (roughly). At least it doesn't look that way for me. Just the short ones.

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  • 2 weeks later...

Richard Hamilton wrote:

stachows wrote:
Yup... just got back from radio shack... 33K ohm, 1/2 watt resistors...

Tried 3 of them same results... They were REALLY cheap lights though... Thought if could use them with a terminator they would look OK.

Hmmm that is puzzling. I just called my colleague in Tennessee to ask if he had any trouble with his terminators and his are also working, but without the terminators, his lights are sporatic.

I would guess that your LEDs don't matter if they are cheap since you mentioned you got them to work with a C9 bulb. That result tells me that there is still not enough load on the circuit by using a 33K Ohm resistor. I did a little experiment just now and I am able to go as high as 45K before the lights start flickering again. Of course going lower on the resistor value will help, but it can't go too low or else a 1/2 watt resistor will get too hot. 33K will use .4 watts at 120 VAC. That should be enough to fool the Triacs into thinking a constant load is on the circuit.

Yea, I expect there to be some differences between the components in various manufactured controllers, but I would not expect there to be enough difference to cause this technique to work on some controllers, but not others. Just to be sure I understand what you did... You put the resistor ACROSS the AC line (like inside of a housing) instead of putting it in series with the lights? Right? It will be interesting to hear of other people's experience and comments.



i went to radioshack and got 33 ohm, 1/2 watt resistors. to try with my LEDs, and when i went to wire them to a plug, then plug the resistor in the well outlet, one of them blow, i then wire 3 of them in series they caught fire and burn out, what could i be doing wrong

james
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I believe they're supposed to be 33,000 ohms or 33Kohms, sometimes referred to as 33K.

Since Current (I) = Voltage (E) divided by Resistance ®, using a 33Kohm resistor would give you:

I = 120 / 33,000 = 0.0036 amps

Power (P) = I x E = 0.0036 x 120 = 0.44 watts (below the 1/2 watt rating of the resistor).

If you really used a 30ohm resistor, then I = 3.6 amps, and P = 432 watts (way way too high, which may explain what happened)....

Does that make sense?

Thanks, Randy

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