1 Topic by Ski52

  • Ski52
  • Ski52
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  • From: Florida USA
  • Registered: 2013-10-23
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Topic: What value of resistor do I need?

My wife has 4 artificial plant groups that have LED' intertwined in them.  They are powered by boxes with 3 AAA batteries.  Well I got tired of replacing a handful of batteries every few days or so, so I clipped the battery box and replaced it with a 5V wall wart.  I used 1 15 Ohm resister, that was in-line inside each battery box per 2 LED strings, soldered in-line.  Gets a little too hot for my liking, and 2 sets get substantially brighter. 
I would like to use one 5V 2A wall wart to drive them all.  What resistance is required to hook all 4 to 1 power supply?


TIA for any help

Ski

Ender 3 Pro

2 Reply by Tin Falcon

  • Tin Falcon
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Re: What value of resistor do I need?

http://www.ohmslawcalculator.com/ohms-law-calculator

a resistance of 3.3333 ohms at 5V will draw 1.5 amps. 
the above calculator should help you.

tin

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3 Reply by Ski52 (edited by Ski52 2016-09-03 17:51:07)

  • Ski52
  • Ski52
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Re: What value of resistor do I need?

Tin - thanx for the help. 
Got some figgerin' to do...

Ski

Ender 3 Pro