PC gas analyser optimized location

Hi expert

for 2 string 6stage PH what is the optimum position of PC analyser, at PC out let or Cyclone 6 exhuest gas position.

in our confirgation cyclon 5 material feed to PC where as material from PC through riser duct goes to cyclone 6.

as standred matter of practice it's suggest at PC out let but in most plant it's relocated by plant process department at cyclone 6 exhuest.

is some one can give inside look ...............

Regards.