Simply, IQ Gateway is using differential mode signal over L1 and L2, so, Only differential noise filtering will hlep enovy. I have tried on the various configuration.

 

when install 3 ferrite on L1, and 2 ferrite on L2, shows the best result.

if double turn on ferrite, it can help a lot, BUT, ferrite can be saturated too easily.

 

 

L1x2,L2x2.JPG

L1x2x2,L1x2x2.JPG

L1x3xL2x2.JPG

L1x5.JPG

L2x5.JPG

L12x4.JPG