Abstract: A method of measuring low conductivity of a liquid sample using a contacting-type conductivity sensor is provided. The method includes applying a first excitation current to a contacting-type conductivity sensor at a first drive frequency. A first voltage response to the first excitation current is determined. A second excitation current is applied to the contacting-type conductivity sensor at a second drive frequency higher than the first drive frequency. A second voltage response to the second excitation current is determined. A conductivity output is provided based, at least in part, on the first and second voltage responses. A system for measuring conductivity of a liquid at or below 100 ?S/cm is also provided.

Abstract: A method of operating a process a combustion analyzer having a measurement cell is provided. The method includes exposing the measurement cell to exhaust of a combustion process where fuel and oxygen are combined in a burner to produce a flame. The measurement cell is heated to a temperature above a flashpoint of the fuel. When a condition is detected, such as a fault or abnormal situation, gas is directed to the measurement cell to form a gaseous barrier between the measurement cell and unburned fuel while the detected condition exists.

Abstract: A process analytic instrument includes an analytical module configured to analyze a process fluid and a removable tube carrier coupled to the analytical module. The analytical module has a plurality of inlet ports in a sealing surface. The removable tube carrier has an end with a plurality of apertures aligned with the plurality of inlet ports of sealing surface of the analytical module. The removable tube carrier fluidically couples a plurality of tubes to the analytical module when the end of the removable tube carrier is biased into the sealing surface of the analytical module.