Field Day 2014 - Test for basic Power Node v.52

During Field Day I utilized my basic Distributed Power Node (DPN) with a very simple firmware load. It is now packaged in a PA60 Ammo-can using a proto-type wooden chassis.

The LCD panel provides the battery voltage reading and the current consumption sampled every 5 seconds. I also implemented a battery low voltage drop off load control. When the battery voltage drops below this preset value the load is disconnected.

I found during Field Day, the 65 watt solar panel handled all my loads while the sun was up. I had just a FT-817 Yaesu radio and a LDG Z-11 tuner. The 10 Ah SLA battery ran about 3 hours past sun down and then dropped the load as designed. However I did find that once the load dropped off the battery voltage came up enough to be above the set point and then re-enabled the load. This was expected but I did not think it would cycle at a 1-2 second rate. The voltage reading will eventually only be part of the drop out routine and will also consider the total amp-hour consumed before dropping loads.

Here is the setup at Field Day. On the far left side of the table is the Power Node. My laptop ran on our group's generator, you can barely see my FT-817 sitting on top the Z-11 to the right of the laptop.

This is the solar panel setup, the mount worked great and I was able to adjust it every hour or so for sun alignment to get max power.

It would have been nice to have the mains battery changer in the the chassis so I could have plugged it into to the generator at night but that is coming in the next revisions.

The wood chassis takes up a lot of room but I think I will still need to go to a bigger ammo-can to hold everything I intend to implement.

Next steps are to design some tests to verify battery capacity using either a known load or adjustable load. I need to get some baseline run-times for the battery.