US Patent 7106046 Current measuring method and current measuring device

A current measuring method capable of reducing the size of a current sensor while ensuring electric insulation easily and suitable for enhancing reliability by preventing heat generation. A current measuring device comprises a printed board (3) having a conductor for measurement (4), and a noncontact current sensor (100) being mounted on the printed board (3), wherein the current sensor (100) is mounted on the surface (92) of the printed board (3) opposite to the side provided with the conductor for measurement (4). Since the current sensor (100) is mounted on the rear surface (92), electric insulation between the secondary conductor of the current sensor (100) and the conductor for measurement (4) can be ensured relatively easy.