willduino:
I'm going right back to the basics with electronics as there's a lot I've never quite understood.I was just messing around with the dimmer tutorial and thought I'd take the voltage and current measurements with 1, 2 and 3 LED's in series.
Here are all the values I got;
Can someone please explain why in the scenario with 3 LED's in series, the voltmeter would show ≈0.4V when checking them individually but then give a higher total voltage?
Also, why is the total voltage lower when only 1 LED is connected?
And finally, why is there no/little voltage across the resistor when there are 2 and 3 LED's?
Thanks!!
Because voltage is relative to something, always. There is no "5v" there is only "5v relative to ground". The voltage on one side of a single LED in the chain compared to the other side of same LED will be the same for each LED.