“All in one” unit in a cabinet with emergency supply for safe supply of analysers. All components (pretreatment, reverse osmosis, pressurised tank, polisher for residual desalination as well as 0,2 μm sterile filter) are integrated and premounted ready to connect. Optionally available with UV-disinfection and degassing unit. Multilingual microprocessor controller with LCD display for controlling and monitoring pure water systems. Display of permeate and pure water conductivity. Fully automatic rinsing cycles, potential-free fault reporting relay. Module-based capability of increasing capacity at a later stage.