| 摘要 |
PURPOSE:To eliminate an influence on analog signals made flow to a transmitter loop at the time of connection to the transmitter loop. CONSTITUTION:In this communication equipment for superimposing digital signals on a field equipment for originating the analog signals corresponding to a process amount and a signal line for transmitting the analog signals, transmitting the data of contents different from the analog signals and performing bidirectional communication with the field equipment, a time constant circuit 21 composed of a resistor 22 and a capacitor 12 is provided in a connection part with the signal line for transmitting the analog signals and the resistor 22 of the time constant circuit 21 is short-circuited by a switch 23. |
