| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a current input circuit having a simple configuration, when various kinds of current measuring values in an electric-power system are converted into values suitable to a protection control apparatus. <P>SOLUTION: The current input circuit converting an input current measuring value in the electric-power system within a predetermined level is constituted to make the current measuring value flow into a plurality of detecting resistors 5-1 to 5-3 switchable via a switching unit 6, in such a form as to convert the current measuring value into a voltage signal. A plurality of detecting resistors are set corresponding to a plurality of predetermined measuring ranges, and a switching command 10 is outputted from an MPU 9 to the switching unit to switch the measuring range, according to the level of a digital signal inputted to an A/D converter 8. <P>COPYRIGHT: (C)2010,JPO&INPIT |
