Guess this fits this category…
Looking for an Arduino guru to help me out with something. I’ve written a small Arduino program that is supposed to drive a solid state relay on a brewing rig.
It’s got an LCD shield over the top with 4 buttons to adjust the ‘power’ of the heater. Essentially, I’m running a 2 second cycle that has an on segment for x% and an off segment with (1-x)%.
Simple enough… got it to run exactly as expected when I have the ‘driven pin’ as pin 13… the onboard LED.
at 0%, it’s always off, at 100% it’s always on, and at any % between it is correspondingly on then off.
HOWEVER…
Now that I’m ready to drive the external SSR, I’ve soldered 2 wires in, the first to Digital Pin 02, and the second to one of the three +5V pinouts.
When I initialize the program, I have it starting at 0% by a digitalwrite(Pin02, LOW)
However, my multimeter shows an output of 2.75V.
I can do the same thing and initialize it to HIGH, but it still shows the 2.75V.
NOW THE CRAZY PART:
As soon as I move it away from 100% on or off, it works just fine; the voltage briefly jumps to 5V and then 0.
When I go back to 100* or 0% it just goes back to the 2.75V
What am I missing to get the initialization to to be 0 or 5V?