DC Power Meter Re-Wire

DC power meter was wired incorrectly and that caused some issues with the accuracy of the reading. I think I mixed up the shunt wires do to having to flip the meter and case over to wire it and thus swapping the load and source sides.

Initially I just swapped the 2 pickup wires on the shunt in order to have a "positive" current flow and that seemed to make the meter read amps and watts. However, the readings seemed to be inaccurate and that came down to having the meter "-" terminal connected to the load side of the shunt, I think that few mV difference between the source side of the shunt and the meter "-" caused the reading errors. Along the way, I must have also worked one of the wires loose in the meter connector block.

After having to pull the meter off the board a few times to work on it, I didn't want to take it off again after I got it working to shoot some video. It's hard to get a camera in there without completely removing the meter.

As far as meter accuracy, I think it's reasonable. It reads a bit higher than my clamp meter but a bit lower than the mV reading across the shunt with a 4-1/2 digit multi-meter. The voltage at the meter also seems to read a bit low, but I think overall, the watt and KWH readings are likely OK. Since I can't calibrate the meter, it is what it is.

Using a PZEM-051 DC power meter:
https://amzn.to/3VBFvJZ

Meter enclosure:
https://www.thingiverse.com/thing:1830137

Link to the thumbnail image with a description below:
https://photos.app.goo.gl/rX1zeyZc76sc7RvHA
Image credit: https://www.rcscomponents.kiev.ua/datasheets/pzem-051-datasheet.pdf

This project has taken over a year to complete, so videos have been shot at various times over that period.

More to come...
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