Samun ingantaccen ƙarfin dumama, ana amfani dashi galibi azaman babban canji ga duka biyun
tashar tashar tashar kayan aikin lantarki, da harka hada hasken wuta, da zuwa
contraral injuna iri-iri da ƙananan kayan wutan lantarki haka nan, ba shi da wani aiki
na kariya daga over load short-circuit.