Silicon ring core with copper wire has been used in the current transformer manufacturers. With this copper wiring current flow easily as copper is a good conductor of electricity. Winding is a significant part of the current transformers. Thus, core copper wiring is done for the easy flow of electricity. Its accuracy is enabled by the opening center of the device. The shape and sizes of the current transformers depend on its usage. Low voltage meters are either of ring-type or plastic molded case.