PRECISE CAPACITY CONTROL
Powerstream’s compact semi-hermetic screw compressors are distinguished by a further improvement in energy efficiency at full and part load conditions. Accordingly, these compressors exceed the international efficiency standard of compact screws with respect to the seasonally weighted energy requirements to an even higher degree than before.
Each unit in the range equipped with a pair of compressors on a single circuit and starts with the one driven by the inverter-fed motor. As the cooling demand exceeds its capacity, the control system of the chiller starts up a fixed-speed compressor and adjusts the speed of an inverter-driven compressor accordingly to the actual load. When the cooling demand decreases, the control system stops a fixed-speed compressor and regulates the speed of an inverter compressor as required. Additionally, the chillers feature low in-rush current, hence lowering the installation costs.