| 摘要 |
<p>A fiber-optic data-link (10) used to interface a remote process variable sensor/transmitter (14) to a local process control system (12) includes a local light source module (16) and a remote interface module (18) interconnected by one or more optical fibers (20, 22). Energy for operating the remote interface module (18) and its associated process variable sensor/transmitter (14) is provided by light energy transmitted from the local site to the remote site and converted at the remote site to an electrical signal. The local light source module (16) and the remote interface module (18) each may include a microcontroller (24, 34). The controllers not only control the flow of status messages in either analog or digital analog form simultaneously from the remote site to the local site, but also ensure the integrity of the system and minimize the amount of optical power delivered to the remote site.</p> |
