PURPOSE: To uniformalize electric current which flows in each superconductive wire by containing a normal conductive metal in parallel part at the time when a plurality of superconductive wires are connected to the normal conductive metal in parallel and uniformalizing the resistance value of each wire connected in parallel.

CONSTITUTION: At the time when two superconductive wires are connected to normal conductive metal in parallel, normal conductive wires 3a, 3b are connected in series by soldering between the metal 2 and superconductive wires 1a, 1b. The metal 2 is divided into two branches 4a, 4b and each branch 4a, 4b and each superconductive wire 1a, 1b are connected to each other by soldering. In the equivalent circuit, R1, R4 stand for connection resistance and R2, R5 stand for resistance of the normal conductors. The electric currents i2, i2 (i1+i2=I) flowing in the conductive wires 1a, 1b can be expressed as an expression I. Since the resistance of the superconductors is zero and the connection resistance R1, R2 is sufficiently low as compared with the resistance R2, R5 the expression I can be transformed to the expression II wherein since R2, R5 depend on the superconductive wires 4a, 4b, R2 becomes equal to R5 and thus i1 becomes equal to i2.