CLASS CHARACTERISTICS LINK WITH MIC

Kindly guide me How we will link with class characteristics to MIC to different plants

EX;- i have class characteristics Fe,S,P,Al2O3,SiO3 so i created class characteristics without out values then after that i will link with same characteristics MIC plant level first plant system should allow next plant when i link with MIC system give the Erros messege as a "CLASS CHARC.IS ALREADY LINKED WITH MASTER INSPECTION CHARAC.FE IN PLANT1000"

how we will link with same class c