Are my LED strings in parallel or series?

Other Hardware LEDs and Multiplexing
1

I've completed two projects now, where in both of them I have made strings of LEDs where they are physically connected to each other. no breadboard. just the anodes and cathodes of each LED bent at 90 degrees to connect to the anode and cathode of the next. there are no resistors at all, and each string is connect by a jumper lead to the arduinos digital pins.

on every string the connections are anode - anode and cathode - cathode.

one project is 10 strings of 28 LEDs, the other is 8 strings with strings varying in size from 9 to 64 LEDs.
so far I have encountered no problems, but I would like to clarify a few things before I try anything new.

1.) have I wired these strings in parallel or series? anode to anode and cathode to cathode.

2.)do i actually need resistors? surely the strings are long enough that the resistance is sufficiently high enough?

2

  1. Does it matter? As long as you're happy that it works, what's the difference?

  2. No, resistors are a conspiracy of the component manufacturers. They're unnecessary, tools of the electronics theocrats to keep people down and from achieving their dreams.

3

Haha, that was my initial thought, but I was worried I might destroy the arduino by doing things my way.

thanks for the reply

4

FiascoDaze:
2.)do i actually need resistors? surely the strings are long enough that the resistance is sufficiently high enough?

Maybe not if the LEDs aren't reaching the bend in the power curve.

OTOH it would take about ten seconds to grab a multimeter and measure it.

5

Sounds like parallel connections if anode-anode and cathode-cathode.

What is driving all these strings? Direct from Arduino pins?

Put a meter in series betwen one end of a string and the current source (anode end) or the current sink (cathode end) and see how much current is flowing.