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L.E.D.`s - series or parallel?

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Re: L.E.D.`s - series or parallel?

If this were me, I'd put strips of LED next to each other to give maximum coverage and maximum LEDs. I'd then get a circuit that could control the brightness of these so it it is too bright and can be turned down or turned up for use with thicker paper. Just saying.

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Re: L.E.D.`s - series or parallel?

Just a reminder that these LED strips need a PWM controller source to work, you just can't apply a voltage directly to them. So this would mean using the likes of an Arduino or Pi to control them. But having said that you could create yourself a very elegant solution if you do decide to use them.

PWM = Pulse Width Modulation

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Re: L.E.D.`s - series or parallel?

@Mook  thanks for that very valuable information....I have just sent you a more detailed PM.

cheers

Wink

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Hero
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Re: L.E.D.`s - series or parallel?

@Mook 

I think that you are getting confused. Certainly the LED tape that I have used is a simple arrangement of parallel LEDs each fitted with their own individual series resistor.

I have just tried a length on an analogue variable dc power supply. They start to come on at around 7V and progessively increase in brightnes until I get to the rated 12V. There is no need for a PWM power supply, in fact a single series resistor of sufficient power rating would do the job fine.

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Re: L.E.D.`s - series or parallel?

Fair enough @Baldrick1 maybe you could let @shutter know the part number and where you got them from please.

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Hero
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Re: L.E.D.`s - series or parallel?

@Mook 

Will do with pleasure. I'm wondering whether you are confused by companies selling PWM dimmers?

If so they use PWM rather than a series resistor because they will work with any length of tape up to the maximum rated current of the dimmer. If you use a series resistor it has to be 'tuned' to the length of tape. Analogue dimmers are more expensive to make these days and get hot.

It's not that you can't run the tape at a lower voltage.

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Hero
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Re: L.E.D.`s - series or parallel?

@shutter  @Mook 

If you've followed the last few posts then this is the stuff that I used but I have little doubt that they all work the same way.

https://www.ultraleds.co.uk/search/searchresults/?search_query=30+x+5630+Led+40+Lumen+per+Led+1200+L...

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Re: L.E.D.`s - series or parallel?

My assumption @Baldrick1 was based on my own experience of these as I have them fitted  in my house (Philips Hue) and these require a PWM controller and the majority of others I've came across also require PWM and can be addressed and operated using I2C. Hence my reference to Arduino and Pi.

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Hero
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Re: L.E.D.`s - series or parallel?

@Mook 

That's the posh end of the market. As he keeps reminding us @shutter comes from Yorkshure!

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Re: L.E.D.`s - series or parallel?

@Baldrick1  Thanks for the linky... looks as though most of that stuff on there is "high wattage" output.... so probably too (light) powerful for what I am looking for..

still considering using 5mm internal diameter plastic tubing in strips across the screen area... with the led(s) poked in the end... will be easy to fix in position and add further strips if the spread is not sufficient.

but... all is on hold for a while, as I have some other more important stuff going on now.

thanks to all for the input..

cheers

 

 

P.S.. talking of posh.... it "Yokshur"   .not Yorkshure !