Isixhumi esidibeneyo sinqamla isixhobo sokumisa intambo kumsebenzi wenethiwekhi ukuba kwenzeka ukugqithiswa okukhulu, okubangelwe, umzekelo, kukutshayiswa kombane kufutshane, ukuphuma kwe-voltage engavumelekanga kwinkqubo. Ukuba oku kuyenzeka, ipleyiti yokulinganisa engaphantsi kwesixhobo sokumisa intambo iyaphuma kwaye ihlale ijinga kwintambo yokubamba. Uqhagamshelo lomhlaba ngokwalo luhlala lukhuselekile. Olu lungiselelo luqinisekisa ukuba xa isixhobo sokumisa intambo siqhamla, umgca woqhagamshelo lomhlaba awunakungena okanye iindawo eziyingozi zenkqubo ephezulu. Ipleyiti yokulinganisa inkulu kwaye iyakhanya ngasemva, ngoko isixhobo sokumisa esingenasiphako sibonakala lula. Zonke ii-terminal zenziwe ngentsimbi yodidi oluphezulu kwaye ziqhagamshelwa kwi-aluminium okanye kwi-copper ngaphandle kweengxaki zokubola.