SWITCHING METHOD OF MEASURING DEVICE

PROBLEM TO BE SOLVED: To provide a switching method of a measuring device measuring current flowing in an apparatus without causing a power failure in a power system.SOLUTION: In the switching method, a state where a first measuring device 30 is connected in series is switched to a state where a second measuring device 35 is connected in series between the first measuring device 30 and the second measuring device 35, which are connected in series for measuring the current of the apparatus installed in the power system. The method includes: a first step for connecting an element 60 changing a state where the current of the apparatus flows to the first measuring device 30 and a state where the current does not flow to the first measuring device 30 in parallel; a second step for setting the state of the element 60 so that the current of the apparatus does not flow to the first measuring device 30; a third step for connecting the second measuring device in series and removing the first measuring device 30; and a fourth step for setting the state of the element 60 so that the current of the apparatus flows to the second measuring device 35.