Which is the best secondary connection to clean the main line power from EMI, line noise and HF harmonics by using an isolation 1:1 230/230VAC transformer with balanced outputs:
1) A floating (C1 and C2 are enough)
2) A to C to ground via a small capacitor
3) A to B ground directly
After having determined that connection for EMI suppression purpose ONLY, how to connect D ground output just for safety purpose (D to A, D to B, D to C, D to nothing)?
FYI: the transformer is multi shielded and each shield is connected to B ground. It has also a copper belly belt, currently floating.