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When connecting LED's in parallel is it better for each LED to have a resistor or a single resistor at the start? Answered

I am trying to wire 27 LED's in Parallel so that they can work independently of each other. 

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shams (author)2011-10-03

Each led must have separate resistor.Its a must !...If your having problem with calculating resistor value give me your specs I can calculate for you

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Tzoul (author)shams2012-02-28

Thank You! Would you solve my problem? I am using a 14.8v power source to light 16 bi-colored leds in a parallel. I understand I need 32 Resistors, but what strength? My led specs are like this: 2.9v draw, 25mA, Please help. When I enter this into the many resistor calculators Ive found on the web, they give me such incredible resistor suggestions, however I wonder if this accounts for each led. Another thing I can not rap my mind around is that: occasionally I will have both colors on at the same time. How do I figure that into all this resistor calculating.
The leds are three pronged and 5mm, thanks in advance.

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shams (author)Tzoul2012-02-29

by strength are you saying about wattage ? If so you can use 1/4 watt or 1/8 watt resistors.And you dont actually need 32 resistors !!...just connect a resistor on the common pin of the LED ..if your leds are common anode then put resistor on anode ,if it is common cathode then put resistor on cathode.

I hope I have answered your Q ..8D

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Tzoul (author)shams2012-02-29

Thank you shams,

I sorry I didnt provide enough info to start. The leds are bi color three leads 2 anodes and 1 cathode. Im hooking up 16 of these monsters to a 14.8v power supply. Im inserting a "house lamp" switch; this will give me the option to have one color on at a time or both on (both green and blue "on" makes its it more of a white light). Because of the bicolor nature of this project I must wire in "Parallel". Now! everyone says " when wiring it is best for each led to have its own resistor, makes sense. The 5 online "resistor calculators" I've been exploring, dont account for this rule. What you think?

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steveastrouk (author)2011-08-31

Single resistor with each LED.

What are you trying to do ?

Steve

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Kaisei13 (author)steveastrouk2011-08-31

A game board. Each piece would contain an led and when place on the board they with light up with the players color. I haven't worked much with LED's before so I'm not sure if this will work how I want it too.

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