POWER DISTRIBUTION NETWORKS FOR ELECTROCHROMIC DEVICES

The invention relates to a system and method for monitoring and maintaining a power distribution network of optically switchable windows of a site, the system comprising a control panel monitor configured to cause: determining a control panel voltage and current at a terminal of a control panel; sense circuitry configured to cause: determining a first window controller voltage and current for a first window controller of a plurality of window controllers; and one or more controllers configured to cause: generating voltage network data based on a combination of the control panel voltage and current and the first window controller voltage and current, and determining an error condition in the power distribution network based on the voltage network data.