| 摘要 |
PROBLEM TO BE SOLVED: To obtain a superconducting device having high reliability, in which the generation of oxidization or dry area of a contact surface due to arcing of a first mechanical persistent current switch can be prevented, and increase in the contact resistance at the pole closing operation is eliminated. SOLUTION: This device is constituted of first and second mechanical persistent current switches 21 and 22 connected in parallel, sequencer 23 for controlling the opening and closing operation of those mechanical persistent current switches, exciting ammeter 10 for obtaining currents running through a superconducting coil 1, and power source ammeter 11 for measuring currents which are supplied by a DC source 2. The measured value of the power source ammeter 11 is compared with the measured value of the exciting ammeter 10, and when they match, the pole opening operation of the two mechanical persistent current switches is operated in the order of the first mechanical persistent current switch 21 and the second mechanical persistent current switch 22. |
