Communication Systems for Gas Measurement Data

摘要

This is a rewrite of my 2006 ISHM paper;it contains revisions and additional content.Communications systems range from the simple to complex;we have a lot of choices to make! Making the best choices and avoiding the pitfalls can mean the difference between success and failure.Many good papers describe the SCADA system;this discussion is focused on the connectivity between the SCADA server (Master Terminal Unit),Remote Terminal Units or Electronic Flow Meter (EFM) and Programmable Logic Controller (PLC).The trend is to locate the SCADA server in a data center or business office,remote from the production field or pipeline.This trend creates demands for connectivity options.The business reality is that we must use capital wisely and control recurring cost while providing the service that our internal and external customers demand.Connectivity must be well documented and maintainable.We must be able to define the quality of the connection and measure it (you can't manage what you can't measure).The connections to remote equipment may be isolated on hard to reach locations and they may be relocated from time-to-time.These and many other considerations may appear to make our decision making task impossible.The reality is that we don't have to choose a single option for all our needs.In fact complex systems usually rely on numerous connectivity methods.Some of the options are described here.