| 摘要 |
PROBLEM TO BE SOLVED: To provide an abnormality detector with which whether a signal transmission means and an oscillation circuit are in a connective state or a non-connecting state can be detected surely, irrespective of the kind of the signal transmission means. SOLUTION: An oscillation output from the oscillation circuit 1 is supplied to a signal transmission element 4 via a first capacitor 2 and a first cable 3. A first resistance 5 is connected across the downstream side of the first capacitor 2 and a DC power supply. A second resistance 6 is connected, in parallel with the element 4. A voltage in the connection part of the resistance 5 to the cable 3 is supplied to a first filter 7, to remove oscillation frequency components. The voltage and the first voltage, which is set by a first voltage setting device 8, are compared by a first comparator 9.
|
