Help with customizing LED string

Thread Starter

Tomdas

Joined Apr 16, 2015
6
Hey guys,
I am working on a little project and i was wondering if i could get any advise.
I bought a series of 100 LEDs on a string with the Driver/transformer built into the plug. It had a switch offering 8 different patterns.
What i wanted to do was remove the original plug (pictured) and hard wire them into a lamp i am building. I bought a replacement LED Driver as advised by my local electrical supplier (pictured)
I was hoping that i could have it turn on now with all the LEDS turning on at the same time.
When i wired it up i found that only half the string lit up. As there was no reference to + or - on the wires, i switched them to find that still only half lit up, but this time it as teh opposite ones that lit this time.
I then tried putting both wires in the same input but then had no lights.
Im not an electrical master by any means and LEDS seem even more confusing.
Any ideas?

Cheers for any help in advance
Tom
Original LED Driver and plug.jpg LED Driver replacement.jpg Original LED Driver and plug.jpg LED Driver replacement.jpg
 

Thread Starter

Tomdas

Joined Apr 16, 2015
6
Hey guys,
I am working on a little project and i was wondering if i could get any advise.
I bought a series of 100 LEDs on a string with the Driver/transformer built into the plug. It had a switch offering 8 different patterns.
What i wanted to do was remove the original plug (pictured) and hard wire them into a lamp i am building. I bought a replacement LED Driver as advised by my local electrical supplier (pictured)
I was hoping that i could have it turn on now with all the LEDS turning on at the same time.
When i wired it up i found that only half the string lit up. As there was no reference to + or - on the wires, i switched them to find that still only half lit up, but this time it as teh opposite ones that lit this time.
I then tried putting both wires in the same input but then had no lights.
Im not an electrical master by any means and LEDS seem even more confusing.
Any ideas?

Cheers for any help in advance
Tom
View attachment 84115 View attachment 84116 View attachment 84115 View attachment 84116


Oh, i forget to mention that i asked the original supplier the wattage of the whole string of 100 LEDS and he said bewteen 8 and 10w.
Hope that helps
Thanks again
Tom
 

#12

Joined Nov 30, 2010
18,224
Yes. The half and half response is the clue. What to do about providing the proper voltage and current escapes me.
 

#12

Joined Nov 30, 2010
18,224
I'm afraid the DC label is correct and the polarity control is in the controller box. Your job, should you decide to accept it, is to get both polarities to the LEDs, in an alternating fashion. The obvious way is to use an AC adapter, but the devil is in the details. Can you merely apply some voltage and expect the LEDs to have current limiting already installed in the light string? I think so. You must measure the original output. Problem: You can't measure a fast, chopped, output with a $10 meter. Try to use an AC voltage setting and see if the reading makes sense or just goes random.
 

Thread Starter

Tomdas

Joined Apr 16, 2015
6
Cheers for your responses, am now realising it wasn't as simple as i thought..
Ive taken the original plug to pieces and wired in the transformer to the unit I've made but the default setting is flashing between alternate lights. I wonder if there is a way of getting the default to have both sets in.
Ive attached a pic showing both sides of the circuit if it helps.
So i guess i need to find an 240vac to 32vac transformer?

Cheers
Tom
led driver circuit board front.jpg led driver circuit board back.jpg
 

Dodgydave

Joined Jun 22, 2012
11,395
you could use a 555 timer oscillator with four mosfets, in an H bridge switching your leds , or just put a transformer on the leds directly.
 

Thread Starter

Tomdas

Joined Apr 16, 2015
6
you could use a 555 timer oscillator with four mosfets, in an H bridge switching your leds , or just put a transformer on the leds directly.
Excuse my naivety, but what do you mean by put a transformer on the leds directly? is that not what i did?
 

Dodgydave

Joined Jun 22, 2012
11,395
no ,you put a DC power supply on the leds, you need to put a transformer pure AC, so that both sets of leds will light up,the original black psu will reverse the dc output, so it makes them all light.
 

Thread Starter

Tomdas

Joined Apr 16, 2015
6
no ,you put a DC power supply on the leds, you need to put a transformer pure AC, so that both sets of leds will light up,the original black psu will reverse the dc output, so it makes them all light.
Cheers, I'm having trouble trying to find a 32volt AC transformer. Any ideas where i can get one? I tried with an ac adaptor but it only went up to 12v which was not enough power.
Seems like 12vac transformers are everywhere but 32vac transformers seem illusive.
thanks for all your help and advise
Tom
 
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