Patent ID: 8258794

Claim:
A measuring device for carrying out purity measurements in a water circuit in a steam turbine in a power station, the steam turbine having at least first and second different operating modes, comprising: an ion exchanger device having first and second selectable flow paths for movement of steam turbine water through the steam turbine water circuit during operation of the steam turbine and first and second ion exchangers, which each removes the same alkalizing medium with an acidic cation exchanger through identical ion exchanging processes, which effects removal of impurities of a type that cause damage to an evaporator or turbine blades, the first ion exchanger positioned in the first flow path and the second ion exchanger positioned in the second flow path, the first ion exchanger being smaller than the second ion exchanger so that water can be flushed through the first ion exchanger in a relatively short period of time during turbine startup, compared to the amount of time required to flush water through the second ion exchanger during normal operation of the steam turbine, the measuring device including one or more first valves for selecting movement of the steam turbine water through the first flow path during start-up in the first operating mode of the steam turbine and one or more second valves for selecting movement of the steam turbine water through the second flow path during normal operation in the second operating mode of the steam turbine, wherein the first operating mode is a startup mode of the steam turbine; and at least one measuring unit for alternately measuring a parameter of the steam turbine water flowing through the first and second ion exchangers of the ion exchanger device, the device enabling measurement of conductivity from a relatively small volume filter during startup in the first operating mode and measurement of conductivity from a relatively large volume filter during normal operation in the second operating mode.