LED power supply help

[Ianw]

I purchased 3 LED Christmas Trees a couple of years ago. 2 of them have packed up. I believe it is the multifunction control box that has packed up. I know all the LED's work so what I would like to do is sort out a power supply just to light the trees. I'm not bothered about having a multifunction control box which allows you to change the LED flashing sequence.

These are the trees.

http://www.christmastreesandlights....loured-cherry-blossom-tree-with-600-leds.html

Thanks for your help.

 

[Martaine2005]

Hi Ian,
That may not be as simple as it sounds.
It would depend on how they are wired and whether they are single or rgb leds.
I think you need to check what the current is when all the leds are on constant.
The controller should have that info on it.
Ebay has hundreds of led driver/supplies.
I would assume that four wires go to the controller? You will need to find out what each wire is in order to connect them up to a different driver/supply.

Why not contact them 0800 157 7265. Ask if they can supply the correct controllers.

EDIT: Why not open the controller and post pictures here. Somebody might be able to see what is wrong/blown. It may be easier to fix than you think!

Martin

 

[(*steve*)]

it says it used a low voltage transformer. Check first that this is working.

 

[Ianw]

Thanks for your replies.

I have checked the transformers and they do work.
The controller has 3 wires coming from it that go to each branch of the tree. Each branch has 2 circuits. The LED's are wired in series on each circuit. Each circuit has one wire that connects to the negative and the other two wires are connected one to each circuit. I assume these are the positive. I have opened the controller but can't see anything obvious that has blown.

 

[Martaine2005]

Hi Ian,
If the transformers are ok, there is a little work around to get rid of the controller altogether.
Although only 24vac care should still be taken at all times.
The two are more than likely negatives to each channel and the single wire is probably a common positive.
Do you have a multimeter? It would make this very easy.
You need to confirm the positive and negatives though.
Easiest way is to use a bridge rectifier from the 24v transformer and the positive and negative from the rectifier to the lights. Just a common 50v 1 amp rectifier.
But, however, etc, beware that the leds may have resistors that are not adequate for running the lights constantly. You'll soon know though! They will get very hot!.
Keep all connections properly covered / encased.

Martin

 

[Martaine2005]

Sorry, should have also added that there isn't much to go wrong except the blob ic.
The diodes can be checked with a multimeter and the thyristers can be shorted to check them.

Martin

 

[M-Bagheri]

Hello
I think the circuit will solve your problem in the following URL suck
electrical circuit

 

[Ianw]

Hi Martin,

I will get a rectifier tomorrow from Maplins. I have a multimeter that I can check which is positive and negative. How do I work out which is negative and positive on the LED's. Will they blow if they are connected the wrong way round?

Thanks for your help.

 

[Ianw]

Hello
I think the circuit will solve your problem in the following URL suck
electrical circuit

Thanks for your reply.
The link you sent shows

 

[Ianw]

Sorry I should have typed....

The link you sent shows 120v, my supply is 24v.

 

[Martaine2005]

Hi Ian,
You can check the + and - on the controller easy enough, the + will go up to the diodes.
The - from the leds will go to the two PCR 406's.
It should be easy enough to follow the tracks back.
You will need to remove the bottom black plastic section to confirm + and -.

Martin

 

[Ianw]

The problem is I have already cut all the wires to the controller and don't know which one goes where now.

 

[Martaine2005]

Never mind. The ac from the transformer doesn't have polarity. Just connect the wires to the tilde sign.~.on the rectifier.
The led wires should be easy to figure out. If you look closely at the led, you will see a flat spot on one side. That is - or the cathode. The + or the anode of the led will have a smaller "element" inside the resin.



Martin

 

[Luis Costa]

rotate the plug?

 

[Martaine2005]

rotate the plug?

What difference would that make if it's ac?

 

[Luis Costa]

oh...
right... shut my mouth!

 

[Martaine2005]

Haha,
You should have responded "if the leds don't work" rotate the DC plug connections!!

Martin

 

[Ianw]

Never mind. The ac from the transformer doesn't have polarity. Just connect the wires to the tilde sign.~.on the rectifier.
The led wires should be easy to figure out. If you look closely at the led, you will see a flat spot on one side. That is - or the cathode. The + or the anode of the led will have a smaller "element" inside the resin.

View attachment 23104

Martin

Hi Martin.

Thank you for your help. I will try this out over the weekend and let you know.

Ian.

 

[Ianw]

Haha,
You should have responded "if the leds don't work" rotate the DC plug connections!!

Martin

Hi Martin,

I have purchased a bridge rectifier and connected it up and the tree now works.
Thank you so much for your help.

I know you probably think I have a nerve for asking but do you think there is a way I could make a small circuit so when half the LED's are on the other half are off and then when they turn on the other half turn off to give a flashing effect.

The LED's have 3 wires which is 2 negatives and 1 positive which makes up the 2 circuits. I was looking at a circuit with a 555 timer IC which looks like it may do the job.

Thanks again.

Ian.

 

[Martaine2005]

Hi Ian,
Glad it all worked for you. Hope you insulated the connections properly...

Yes, you can certainly use a 555 to do that.
It's a real easy circuit and you can choose or work out what flash rate you like...
I will find a real easy video for you to follow and post it here. He is a great easy to follow guy.
I like his videos a lot...
Have fun...

Martin