Liebert® EXL S1 delivers secure power while providing first class load protection and maximum energy saving for medium-large data centers and mission critical applications. The latest high efficiency Dynamic Online mode enables operating efficiency up to 99% without sacrificing availability. Liebert EXL S1 Dynamic Grid Support feature can provide frequency regulation by controlling the input power to support services such as frequency regulation-up, regulation-down, or both via charging and discharging of the battery.