These vacuum controllers have a chemical-resistant precision pressure sensor with capacitive measuring principle and an integrated ventilation valve that opens if there’s a power failure and prevents over-pressure in the system. Easy operation with rotary knob and large graphic display. Menus available in 6 languages. The V-850 vacuum controller features the following advantages: Vacuum regulation to a specified set-point, Library with 43 specified solvents, Timer function, Büchi wizard for quick configuration, USB interface for data transfer and control of quick-action jack and rotation on the RotaVapor. The V-855 Controller has all the features of the V-850 plus EasyVac function (together with vacuum pump (V-700/710): automatic processcontrol based on vapor pressure detection. Additional features include: Automatic distillation with the unique stage probe, Programming function for pressure gradients for special distillation tasks: storage of up to fifteen process profiles with programmable gradients. Ideal for compounds that “bump” and for products that are difficult to distil, e.g. foaming extracts. Repeat function for reproducible repetition of a distillation: the pressure profile for a manual or automatic distillation is displayed and can be retrieved at any time.