For easy measurements, I use a Tripler Board, INA219, and OLED screen, all available from the Particle Store, currently for $28 total.
The picture below shows the testing of a 2W Voltaic Solar Panel.
The Li-Po Positive conductor runs through the INA219 screw terminal, measuring the Current Entering or Leaving the Li-Po and the operating Voltage.
The Code samples the INA219 as fast as possible (168 times) during a 1-second time slice, and reports the following values on the OLED screen each second:
- mA for the last second (charge or discharge)
- Li-Po Voltage
- mW for the last second (charge or discharge)
- mW Average for the entire runtime
- mWH NET for the entire runtime (deficit or surplus).
- Seconds of runtime
- number of Samples measured during the last second (SPS, or samples-per-second)
This makes quick work for testing Firmware changes (
SystemPowerConfiguration) and various Solar Panels in actual sunlight conditions.
I originally used a xenon on the Tripler Board to operate the INA219 and the OLED, with a slightly different wiring layout. That enabled me to have a separate Li-Po for the Boron being tested.
I determined it’s not worth the effort, and now just use the Boron as shown in the Picture for typical testing.
I still use a Xenon on the Tripler to check if a Boron recharges during/after sleep events… but no problems so far with 1.5.0-rc1.
The Boron’s typical usage is 64 mW by itself. Adding the INA219 and the OLED increases this to 100 mW. Just remember that the code reports the energy entering or leaving the Li-Po. IE: a 0 mW result means the typical 100 mW demand is being sourced by the Solar Panel, with no surplus available. This 100 mW changes to 64 mW for the Boron ONLY if you decide to operate the Tripler with a Xenon instead and measure the Boron’s independent Li-Po (requires a common Ground wire).
So far I haven’t found any problems with Solar Charging on 1.5.0-rc1.
I would love any suggestions for improvements to the Code, LINK.