| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a measuring system capable of preventing an operation of a system from getting unstable due to increase of the number of extension units. <P>SOLUTION: A processing section 10 in a main unit M applies a constant voltage to an information line 4 in a state that a switching part 15 is opened after starting up, and measures a current value flowing through the information line 4 to calculate a combined resistance value of resistive elements connected to the information line 4. The processing section 10 compares a total amount of maximum consumption current of all increased extension units S1-S3 (400 mA) and an upper limit value (400 mA), and when it is determined that the total amount is lower than the upper limit value, the processing section 10 closes the switching part 15. Contrarily, when the total amount of the maximum consumption current of all increased extension units S1-S4 exceeds the upper limit value, the processing section 10 in the main unit M does not close the switching part 15. Therefore, since the total amount (summation) of the maximum consumption current of the extension units S1-S3 does not exceeds the power supply capacity of a power supply section 14, any operation of the main unit M and extension units S1-S3 is prevented from getting unstable. <P>COPYRIGHT: (C)2013,JPO&INPIT |
