I have a proposed installation of 10,000 LED pixel lights attached by suction cups to a multi-story atrium for a period not to exceed 90 days. This is considered a sign and will show video as well as wording.The LED lights are driven by 9 controllers mounted out on the windowsills. My question is, would the 90 day time constraint given in 590.3(B) allow extension cords (hard usage) and power strips to power the controllers.