The PBT SC4 site controller is a 4th-generation design based on a secure and powerful Linux computer foundation. The unit is very small, has no moving parts, and can be powered from a DC power source (battery or fuse panel) or from a local AC utility outlet. Each controller can gather data from up to 240 battery sensors, arranged via 6 inputs of 40 sensors each. Maximize the capacity by using virtual string logic or gain deeper insight by matching inputs to physical strings. The site controller has extensive, user-definable configuration, including labels and alarm thresholds for every monitored element. The SC4 can also track float charging, ripple, and discharge current on each string, via current monitoring sensors made by PBT.