Supercapacitor Solar Project Life

[mhaggerty]

I followed the instructions to build the solar panel project using a 6V 1W panel (and another using a 4.5V 1.5W panel) with the 5.4V supercapacitor purchased from here.  The supercapacitor charges up to 5.4V and will power a weathermote (v1 with a v2 Moteino) using the unmodified sketch from here for only a few hours before voltage drops to low to continue running.  I am using a 1N5819 diode so I do not think power is draining back to the panel.  Any thoughts on why this may be happening?  Are my V2 Moteinos less power efficient than newer revisions and pull too much power?  Thanks in advance!

[Felix]

It means it's draining more power somewhere, you'll have to find out where. First thing is you need to measure the sleeping current, then you have something to look into.
The R2 Moteinos are basically the same, the LDO might be 1702 (lower VIN upper limit), still low quiescent current.

[wile1411]

Make sure you have the serial output commented out to turn it off when testing lifespan.
Specifically, check that the double slash is before define line

Code Select Expand

//#define SERIAL_EN

I found that'll drain it a bit quicker than expected when I accidentally left it on.

[mhaggerty]

Great callout!  I had the serial output on and was pulling ~65mA.  After I turned it off at rest I was closer to 0.3mA. 

[HeneryH]

Great callout!  I had the serial output on and was pulling ~65mA.  After I turned it off at rest I was closer to 0.3mA.

Wow. I need to revisit my sketches to turn off serial.  I know that I have forgotten on many of them.

[wile1411]

Yeah - however, it's highly dependent and how many serial calls you have in there. Also - you'll see it a lot easier with the solar project. As I'm still experimenting with my project and trying to working out what's happening in the MCU, I probably add waaay too many debug lines in order to know what's going on. The end result is that I quickly know when I've forgotten to comment out the SERIAL_EN line.

Glad it helped fix the issue.