Читать книгу Automation of Water Resource Recovery Facilities - Water Environment Federation - Страница 130

An I/O list tabulates the actual input and output points for each signal shown in P&IDs. It describes each point, noting its type (digital or analog input or output), associated PLC or DCS processor, and engineering units (units of measure that are useful for operators). The I/O lists are also used to identify internal addresses or I/O points transmitted via a data link for data and/or control that need to be transmitted between a PLC and human–machine interface/supervisory control and data acquisition (SCADA) software or other PLCs, DCSs, VFDs, and motorized valve networks.