I-Counter Calibrator ye-FCZ-IV isetshenziselwa ukuqinisekisa ukuthembeka kokusebenza kwe-counter ye-arrester ehlukahlukene. Ukuthembeka kokusebenza kwe-counter kubaluleke kakhulu ohlelweni lukagesi. Kuyipharamitha ebalulekile yokurekhoda inani lezinsimbi zokukhanya kwe-arrester ekusebenzeni okuvamile. Ingahlinzeka ngesisekelo esibalulekile kubasebenzi bohlelo lukagesi ukuze bahlole i-arrester. Leli thuluzi lisetshenziswa kakhulu kuma-arrester aphezulu kagesi angaphezu kuka-35kV.