That is a false conclusion. There is nothing about one parallel led string failing (somehow?) that would effect the other strings at all.
There are enough differences in LEDs that hooking them up in parallel, one will draw more current ending up burning it out faster than the others and once that happens, because your circuit's current limiting resistor was designed to supply current to 3 LEDs the amount of current draw on the remaining two LEDs will increase. This increase will quickly burn out your remaining LEDs in a snowball effect.
The above is only true, if I have one resistor limiting the current for each parrallel LED.
If I have a limiting resistor for each parallel circuit, then I dont run into this problem, correct?
Thanks for teaching random people on the internet electronics, Lefty :-)
I am using IR LEDS. Each LED requires 20mA
Hm. That means that I need 200mA and not 600, correct?
(I was thinking 20x30 = 600 but it doesnt work like that, right?)