The intent of this project is to quantify the limitations of existing instrumentation class sensors as they apply to PQ measurements. The primary focus should be on the ‘frequency response’ of existing voltage and current sensors. This parameter can highly impact PQ measurements related to harmonics, transient event classification, true power factor, displacement power factor, as well as true RMS measurements in systems with moderate to high levels of harmonic distortion in the voltage and/or current waveforms. Additionally, the need to understand the limitations of portable sensor devices, such as split-core current transformers and Hall-effect voltage and current sensors should be addressed. The body of work should also note the potential impacts of using local service power transformers for measurements intended to diagnose the primary source for PQ parameters.