Bought the OEM sensor last week.
I am feeding it via pi with 3.3vdc and attaching it to a Karmstrup smart meter fitted last week.
The little green light on the sensor flashes in time to the yellow meter led.
The output from the sensor is normally 3.3 volts and drops to about 2.4 volts when a flash occurs.
I can get the sensor to 0.2v if I shine a light into it.
I tried removing the double sided sticky pad to get the sensor a couple of mm closer to the meter led, no difference.
So I believe my problem is a hardware one, Has anyone run the sensor through a schmit trigger or added a transistor or other electronics to get enough of a differential on the output to create a pi trigger?