So we built 6 transmitters and three receivers. They all work, but no two transmitters give the same reading for the same load.
With no load the output ranges from about 5 watts to about 60 watts. By modifying the VREF constant we were able to bring this down considerably on the most eratic ones. But none came all the way to zero.
Also, I mde a change in the python code that seemed to help:
As downloaded:
- Code: Select all
# sum up power drawn over one 1/60hz cycle
avgwatt = 0
# 16.6 samples per second, one cycle = ~17 samples
for i in range(17):
avgwatt += abs(wattdata[i])
avgwatt /= 17.0
As modified:
- Code: Select all
# sum up power drawn over one 1/60hz cycle
self.aveWatt = 0
# 16.6 samples per second, one cycle = ~17 samples
for i in range(17):
self.aveWatt += wattdata[i]
self.aveWatt /= 17.0
self.aveWatt = abs(self.aveWatt)
With those two modifications it is better, but the output jumps around a lot, pretty much at random within maybe a 10 watt range.
