Need help on Battery LED light set to transformer power convert.

[WBFAir]

Hello all

First time post here.

For a Christmas Village display for the houses, I bought a 15 bulb LED light set that is battery powered that I planned to convert to Transformer power so one, it can be controlled by the house voltage timer system I am using for the other lights, and two, so I don't have to keep replacing the batteries.

Actually I bought a 20 light set too and both originally took (3) 1.5V AA batteries.

So with the 20 light set I got a 120 to 4.5V transformer and soldered it to the +/- terminals and all is good.

Unfortunately the 15 set had this 8 function board in it and also unfortunately, none of those functions include just having all the lights stay on.

So about the only way I was able to find to connect the 15 set to be on all the time was to take out the control board and wire them direct.

I have run them this way and for a few minutes and it seems OK but (and also btw my LED knowledge it limited) I think LEDs can't be run this way correct?

Isn't there some type of electronics that needs to be in place to insure there proper operation and continual use?

Basically, if this is the case, as the 15 set is wired directly to the 4.5V trans power, what ever may have been included of this was definitely in the blinker board and is now gone.

So is this OK or should I do something about it?

Also to point out, as I have this tied into the timer system, this can and does run this even when I'm not home, and as well, the houses in this village set are made of cardboard and are very old. So long story short, I'm really concerned about an possible fire problems too.

Thanks for any help.

 

[WBFAir]

LED's and voltage variance question.

Hello all

I bought some LED battery operated light sets that took (3) 1.5 AA batteries.

I bought these to light some very old and made of cardboard Christmas Village houses.

Now as I wanted these to also be run of the same timer system I am using for all the other indoor light, I have converted then to run off a 120V-4.5V transformer.

Now on both sets, there actually are to many lights for all the houses I have, plus they are to close together for how the houses are set up.

So my thought was and it also seems like this will work with the sets, was to pull some of the lights in order to distribute them as I need to.

Again, this does seem to physically work and by that I mean it seems that the bulbs are wired in parallel as if you pull one, the others stay on.

As well I can confirm this too as it is pretty obvious to just look at the wires and see this is the case.

At any rate, so essentially I can pull as many as I want, but my concern is...

...am I then over volt-ing the other bulbs?

I should mention that I do have some knowledge of LEDs but not much but the one thing I was told was that they mostly and take a bit of a variety of voltage +/- of their design, at least a lot more then a filament bulb can, and not be to negatively affected by that, and or as well do not change their light output much, which I can at least confirm that second part as it does seem to be the case with these.

So does anyone have any info they can give me on this subject?

Btw, one of the light sets was 15 bulb and one was 20 an they both took the 4.5V.

Thanks for any help.

 

[berkeman]

(Two similar threads merged -- are they the same?)

 

[WBFAir]

(Two similar threads merged -- are they the same?)

Not quite sure what was done here, yes they are the same project but.

Essentially, first post is: can I run LEDs straight on DC voltage or does it require circuitry?

Second is, how much of a variance from it intended voltage can a LED be run?

To me seemed like different topics so I made two separate posts.

If that is not how it seen by who ever did this, I guess you get to decide, but I just thought the deference's were enough to warrant two separate topics mainly so any possible responders would not be too overwhelmed to reply to either, and only may respond to one as I am looking for help on both of these subjects and don't thing the answer to one, would answer the other.

 

[berkeman]

Not quite sure what was done here, yes they are the same project but.

Essentially, first post is: can I run LEDs straight on DC voltage or does it require circuitry?

Second is, how much of a variance from it intended voltage can a LED be run?

To me seemed like different topics so I made two separate posts.

If that is not how it seen by who ever did this, I guess you get to decide, but I just thought the deference's were enough to warrant two separate topics mainly so any possible responders would not be too overwhelmed to reply to either, and only may respond to one as I am looking for help on both of these subjects and don't thing the answer to one, would answer the other.

Yes, the posts looked similar enough that they seemed like they should be in the same thread. Although the tradeoff as you say is that there is a lot of info and questions now in this thread.

To your questions, you need to figure out how the LED voltages are being regulated, before you replace too much of any controller boards, etc. They may be regulating using series resistor(s), or with a DC-DC current converter that monitors the LED current(s).

With the parallel LED situation, do you see anything that could be series resistors? Some LEDs have their series current limiting resistor built into them though, so you might not see a separate component. You would need to use a power supply and test resistor to figure out if the LEDs had their current limiting resistors built in.

And on the controller board, are there any switching magnetics components? Either a small transformer or a ferrite slug perhaps?

 

[litup]

Hello all

I bought some LED battery operated light sets that took (3) 1.5 AA batteries.

I bought these to light some very old and made of cardboard Christmas Village houses.

Now as I wanted these to also be run of the same timer system I am using for all the other indoor light, I have converted then to run off a 120V-4.5V transformer.

Now on both sets, there actually are to many lights for all the houses I have, plus they are to close together for how the houses are set up.

So my thought was and it also seems like this will work with the sets, was to pull some of the lights in order to distribute them as I need to.

Again, this does seem to physically work and by that I mean it seems that the bulbs are wired in parallel as if you pull one, the others stay on.

As well I can confirm this too as it is pretty obvious to just look at the wires and see this is the case.

At any rate, so essentially I can pull as many as I want, but my concern is...

...am I then over volt-ing the other bulbs?

I should mention that I do have some knowledge of LEDs but not much but the one thing I was told was that they mostly and take a bit of a variety of voltage +/- of their design, at least a lot more then a filament bulb can, and not be to negatively affected by that, and or as well do not change their light output much, which I can at least confirm that second part as it does seem to be the case with these.

So does anyone have any info they can give me on this subject?

Btw, one of the light sets was 15 bulb and one was 20 an they both took the 4.5V.

Thanks for any help.

Just go to Radio Shack, they make universal power supplies that provide many voltages, including 4.5 v, which is a standard voltage for some radios. They also make single voltage supplies, 4.5 volts is one of them. Not sure what you mean by 15 and 20, you didn't include units. Could be 15 watts? 20 Watts? 15 ma, 20 ma? If you wire the lights directly to 4.5 volts, there may be an internal power converter of volts, probably not, maybe just a current limiting resistor. Here is a link to the proper way to power LED's:
http://focus.ti.com/lit/wp/slva130/slva130.pdf

Don, AKA AI3N.

 

[WBFAir]

To your questions, you need to figure out how the LED voltages are being regulated, before you replace too much of any controller boards, etc. They may be regulating using series resistor(s), or with a DC-DC current converter that monitors the LED current(s).

With the parallel LED situation, do you see anything that could be series resistors? Some LEDs have their series current limiting resistor built into them though, so you might not see a separate component. You would need to use a power supply and test resistor to figure out if the LEDs had their current limiting resistors built in.

And on the controller board, are there any switching magnetics components? Either a small transformer or a ferrite slug perhaps?

Hello guys and thanks for the reply's, as there are two, I'll do my best to reply to each one.

First for Berkman, thanks again for the reply and not look a gift horse in the mouth and I know I asked, but to be honest while I understood some of this and do understand all of the terms an parts you speak of, more though, more of it was over my head and as well not something I think I would have the time to work out before the need for this for the holiday.

So as such I thought that while it is not as good as a wiring diagram, that perhaps a few pics of the control board I took out might help, so I have attached them to this reply and they are at the bottom.

To describe how it was and what I did, this light set which had 15 bulbs was not like most where it had only two or three leads but actually had six. To my best interpretation of it was, one was a positive and then there were five more common negatives, that really to make it known, essentially is one of the ways it was able to performed the various blinking combos. In other words, one of the five commons went to 3 bulbs, then the next to three and so on.

So in looking at the board from its green side, the empty connection to the far upper left was the single positive, and then the next five to its right, were each of these negatives.

So again to describe it, to power the set without this board I just ran the one positive to the positive feed of the transformer, then I soldered all five of the sets negative wires together, and then ran that to the negative side of the trans.

Now for what this board had and again this is just my interpretation, but in looking at this all I see is that one little round chip in the middle, but what this is I don't know. But to me it looks pretty basic and if I had to make a best guess, is just some kind of programmable memory chip used to create the various light combos. But who knows, it could include more.

Btw, to switch between combos, you would push that button you see on the brown side of the board to its upper left and do so consecutively to progress through these combos.

So I don't know if this helps you much Berkman, and I know that was kinda long, but I figured, I'd reply with what I could to best help you with your questions.

Just go to Radio Shack, they make universal power supplies that provide many voltages, including 4.5 v, which is a standard voltage for some radios. They also make single voltage supplies, 4.5 volts is one of them. Not sure what you mean by 15 and 20, you didn't include units. Could be 15 watts? 20 Watts? 15 ma, 20 ma? If you wire the lights directly to 4.5 volts, there may be an internal power converter of volts, probably not, maybe just a current limiting resistor. Here is a link to the proper way to power LED's:
http://focus.ti.com/lit/wp/slva130/slva130.pdf

Don, AKA AI3N.

Thanks for the reply Don and just to best reply and I hope I got all of what you were trying to tell me correctly.

Yeah, if I didn't make it know correctly, I already do have some power supplies.

Lemax, one of the more popular makers of Christmas Village stuff has power supplies.

The one from them I am using for the set I am talking about above is a 120vA/C to 4.5vD/C unit, but they also make and I have a 120V A/C to 3.0vD/C unit

So for the moment I am using the 4.5v unit but and this was kinda why I made the second post, as I will be removing several of the bulbs from the set, I am concerned that I may be over-volting the rest, and so as such, if I am, I may be able to use the 3.0v unit for a safer alternative.

Btw just to hopefully clear this up, when I referred to the numbers 15 and 20, those were in reference to the number of LED bulbs the two light sets have that I am working with. One has 15, one has 20.

Again this too was something that made me think of an issue of voltage as since they both came where they were run off of three 1.5 AA batteries, to my layman's brain, I thought, either there was some electronics for the 15 bulb set that reduced the voltage, or that it could be the opposite where it really didn't matter.

But even if that was the case, I was thinking that there may be a limit to that as again to mention, I am planning to take several of the bulbs out to best create the setup.

So I guess my point is, if end up taking out say, 8 bulbs of the 20 bulb set, should I then use the 3.0v transformer to not over power the remaining lights? And basically the same if I take 8 out of the 15 bulb set?

So hopefully that wasn't all to long and provided you guys with the info you were looking for to best answer the questions I had.

If there is any more you want to know, please feel free to ask.

Thanks for all help