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Old 28-04-2018, 07:48 AM   #1
oncomin5torm
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Default LED series or parallel?

As the topic states I am in a quandary about how to wire my LEDs.

I am having 3 LED 1.8mm size with I believe a forward voltage of 3v.

I am putting them inside my station building which has dividing walls.

I am unsure what Is best, as series would be easier I think.
One wire into the building and then one wire out after the 3rd LED.

I'm just not sure if parallel would work better or not.

Thanks in advance.
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Old 28-04-2018, 08:02 AM   #2
Rog (RJ)
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Series is ok but if one fails then the others will fail to light. You only need 1 resistor for each string of LEDs. The total current taken will be the same as just 1 LED.

When wired in parallel, each LED should have its own resistor. Total current will be the sum of the current through each LED.
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Old 28-04-2018, 09:14 AM   #3
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As Rog says parallel is better. It also gives you the opportunity to use different values of resistor for each led thus giving varying levels of intensity in different rooms, which looks much more realistic IMHO than all windows blazing away and lighting up the surrounding area.
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Old 28-04-2018, 10:18 AM   #4
dtb
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Quote:
Originally Posted by Teedoubleudee View Post
It also gives you the opportunity to use different values of resistor for each led thus giving varying levels of intensity in different rooms,
on the basis of this where could the information be found for resistor values etc, to the un-educated like me me a resistor is just a resistor and I for one would be very interested in obtaining more details.
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Old 28-04-2018, 10:45 AM   #5
Steve M
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This will help DTB.

http://led.linear1.org/led.wiz
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Old 28-04-2018, 10:48 AM   #6
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Try this web site linked below, but you will need to know a few things first.
Input voltage - often 12v DC but can be whatever you have available. LED forward voltage rating also known as Vf. LED rated maximum current also known as If and finally how many LEDs in your circuit.
Link to LED wizard ....SNAP Steve!
Once the resistor value is calculated chose a resistor ohm value of at least the next available ohm rating above the calculated figure and if you want to dim the LED increase that ohm value considerably.
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