china lights

piesrule

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Dec 19, 2010
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Newcastle NSW
David_AVD said:
In that case, maybe order them as 24Vac instead, or where you planning to change to DC later?
Yes, I think ordering them in 24Vac is the way to go for me.

One more question. I have BigW Led's from 2009 and 2010. Am I right in assuming that I need Rectifier and resistors for 2009 lights and only rectifier for 2010 lights?

Cheers, Terry
 

fj

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May 7, 2010
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David_AVD said:
In that case, maybe order them as 24Vac instead, or where you planning to change to DC later?
what makes them AC or DC?

i ordered mine as DC but they actually came with a rectifier on them, so i guess that means i should have been running them with AC input? they worked fine running them off DC SSR's, was that wrong of me?

thanks. fj
 

fasteddy

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fj said:
David_AVD said:
In that case, maybe order them as 24Vac instead, or where you planning to change to DC later?
what makes them AC or DC?

i ordered mine as DC but they actually came with a rectifier on them, so i guess that means i should have been running them with AC input? they worked fine running them off DC SSR's, was that wrong of me?

thanks. fj

All LEDs are best suited for DC as they conduct electricity only 1 way, The AC LED strings just have the rectifier installed to convert the AC voltage to a 'DC' voltage. If running the LEDs from a DC supply then i would remove the rectifier
 

Tabor

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May 16, 2010
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Perth, WA
Running DC through a Bridge rectifier wont hurt.
You will just get the voltage drop across the two diodes that are conducting.
Probably around 1.2-1.4 volts.

If you do just remove the bridge rectifier and run DC, just be careful not to drive the leds at to higher voltage, although I suspect you will be under driving them now.
 

wjohn

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May 22, 2010
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fj said:
David_AVD said:
In that case, maybe order them as 24Vac instead, or where you planning to change to DC later?
what makes them AC or DC?

i ordered mine as DC but they actually came with a rectifier on them, so i guess that means i should have been running them with AC input? they worked fine running them off DC SSR's, was that wrong of me?

thanks. fj
The one good thing about a full wave rectifier on a led string is that you can connect wires either way, polarity won't matter, as the rectifier will forward bias the correct diode pair for the led string.
 

bigvic

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May 23, 2010
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11
hey piersrule

u can actually run the dc leds of an ac transformer, all they do is flash on/off at 60 cycles per second and if u have a display that is constantly flashing u will not even noticed. But maybe the flashing will reduce the life of the leds.

If u use a 24v ac transformer all u need to do is to rectify it , u don't need filtering caps or resisters , but make sure the transformer has enough current to supply the strings, typically each string draws about 300ma so if u use 10 strings u need a 3amp plus transformer and rectifier, but l would go a bit higher to allow for extra length cabling and transformer reactance
 
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