Interfacing programmable logic controllers to electrical distribution monitoring systems

Functions that must be performed in monitoring and controlling the use of electricity in plants include energy management to control costs, predictive maintenance to prevent failures, and diagnostics to minimize downtime. A network tying together metering functions, circuit breakers, and motor protection provides a strategy for successfully implementing such functions. The authors describe how to interface a programmable logic controller to power distribution equipment. Application examples illustrate the cost and capability benefits of collecting data from intelligent sensors over a network, compared with traditional electrical instrumentation wired to input and output modules.<>