1) The document describes a high-speed monitoring system for multiple grid-tied photovoltaic array configurations located at the National Institute of Standards and Technology (NIST). 2) The monitoring system collects data every second from four PV arrays totaling over 500 kW, including two ground-mounted arrays, a canopy array, and a roof array. 3) In addition to high-speed monitoring of the PV production and weather data, the system also records infrared images, sky images, and IV curves to study inverter behavior, module failures, and other performance factors.