this is my first post and this is the first time that I work on energy monitoring and metering.
I have some doubt about connections between active parts at 230Vac and AGND, DGND in ADE7953 datasheet and AN-639.
In my application I need to measure currents using shunt resistors.
In fig.9 AN-639, I see that phase is connected to ground.
But in fig. 35 of the ADE7953 datasheet , the pahse is connected to the 1MOhm resistance and the next filter.
This is the first problem: how can I connect the attenuation network in this case?
It is not dangerous to take an active conductor in the entire circuit ground?
And another question: in this case, where I must connect the neutral line?
The second problem is the following: after the 230Vac section, I'm using a switching power supply (with its HF transformer) that gives output to +12Vdc and the GND is insulated...
How can I connect the "phase ground" to other grounds (AGDN and DGND) if I want to maintain the isolation?
Maybe I need to use 3 different grounds?
Please, could you give me some schematis and/or layout examples?
Thank you in advance,