Electricity reading
The electricity meter dial has a sector that is dark and less reflecting than the rest of the plate.
A series of three reflection sensors (CNY 70) provide feedback from the dials on gas- water- and electricity meters.
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The breakout boards originate from Winford.
A more recent version of the sensors is available for gas and water
The electricity meter dial has a sector that is dark and less reflecting than the rest of the plate.
The gas meter rightmost dial has a mirror surface in the dial's number 6
The rotary dial underneath the CNY 70 has a mirror over 120 degrees.
Notice how two short strips of foam tape hold the sensor perpendicular to the dial surface. This is not satisfying, a more rigorous platform has to be made yet.
Conveniently, two DB25 breakout boards help to organise the cabling