| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a voltage inputting-type positioner of an inexpensive structure wherein, through a simple change relative to the common electric current inputting-type positioner, there will be no excessively large electric current even if connected to the voltage supply side without connecting a load resistance, so that communication will also be possible without impediment. <P>SOLUTION: A voltage/current converting circuit 1-5 is provided in a stage prior to a communication circuit 1-2. An over-current preventing circuit CB is incorporated into the voltage/current converting circuit 1-5. The voltage/current converting circuit 1-5 converts a DC voltage signal V into a DC current signal, and converts an AC voltage signal Vf into an AC current signal. Moreover, the voltage/current converting circuit 1-5 keeps the excessively large current, which would flow into an internal circuit, at a predetermined electric current value or less (e.g., 30 mA or less), when the positioner 1C is connected in error to the voltage source side without a load resistance 6 connected. <P>COPYRIGHT: (C)2013,JPO&INPIT |
