Web tension measurement and control of strips running in vacuum environments are demanding applications. These coating systems e. g. the force measurement sensors for flexible solar panel material or the production of films for capacitors, must meet specific criteria. The measurement systems to be used must meet the requirements for long term stability, seals have to be made of non-gassing materials and the force sensors have to function reliably at elevated temperatures up to 150 °C in vacuum of 10^-7 millibar. Maintaining that type of vacuum requires a hermetically sealed design or pressure equalization holes or the use of bleed screws.