Hey Guys.
Since my stroke I’ve completely lost confidence in my judgement….
The LED strip is 5 M long and labelled 24 Volts. It has been made up from shorter strips, soldered together. Am I correct in thinking that this is the working voltage, no matter the number of LED’s used?
I don’t want to burn the $#!t out them…. 
Cheers Graham.
Infrared LEDs have a forward voltage of 1.2 volts at about 20 mA. So you are looking at no less than 20 LEDs in series. (20 x 1.2 = 24 volts. For longevity, I would use a couple more. If you have more than 20, then parallel each 20 (or more LED strips) up. Or you could have 10 (or more) LEDs per strip and work on 12 volts. Again because 12-volt systems can go as high as 14 volts, I would use a couple more LEDs per strip for safety. In practice LEDs have a lot of tolerance for slight overvoltage - but the problem is you can't see infra-red. If you use your smartphone camera, you may be able to detect when they are on and see how "bright" they really are. An afterthought: You could use a visible LED in parallel across two of your infrared LEDS as a visible indicator that your system is working. If the voltage is too low then parallel the visible LED across three infra-red LEDs.
« Last Edit: Today at 01:39:17 by Aking.21 »
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