Split-core current transformer

A split-core current transformer core comprises a U-core section in combination with a closing-bar core section that has extra length, width, and cross-sectional area as compared to the U-core section, shielding above and below secondary windings wound on bobbins that are mounted around leg portions of the U-core section and extending at least partially along a yoke portion of the core that joins the leg portions of the core, unitary construction and assemblage that accommodates calibration of output signals after assembly of the components in a base module and cover module that is hinged to the base module and has squeeze latches formed in a unitary manner with the cover housing such that they do not require assembly and do not protrude outwardly from adjacent surfaces in either open or closed mode, and other features that minimize magnetic reluctance and increase clearance and creepage distances.