In this paper, the design and implementation of a high-performance, real-time power quality (PQ)-measuring instrument based on a digital signal processor is discussed. The system is realized according to the latest standards about PQ monitoring, and it can be reconfigured for future developments of the standards. The instrument is particularly implemented to operate in stand-alone mode, and it is interfaced with a hardware module that adopts Transmission Control Protocol/Internet Protocol to exchange information and data. The main advantage of the realized device is the possibility to perform a comprehensive PQ monitoring that adopts a single low-cost instrument. Finally, this paper reports some preliminary experimental results of the accuracy characterization of an implemented prototype of the proposed instrument.