A method for operating an inductive conductivity measuring device that has a transmitting coil with an input and a receiving coil, the transmitting coil and the receiving coil being inductively coupled to one another by an electrically conductive medium. An electrical preset alternating signal is generated and fed to the input of the transmitting coil. The method for operating an inductive conductivity measuring device is improved in that a frequency of a preset alternating signal is varied in a frequency interval, in the frequency interval, a frequency-dependent minimum input impedance at the input of the transmitting coil is determined using a response alternating signal, a minimum frequency of the response alternating signal is determined at the minimum input impedance at the input of the transmitting coil, and a conductivity of the medium is determined using the minimum frequency of the response alternating signal.

A high pressure dynamic micro differential pressure gauge, and methods for using and checking the same. The high pressure dynamic micro differential pressure gauge comprises a set of vertical manometer tubes in communication with each other, where one or more manometer tubes are connected to a resistance meter through signal lines, and the resistance meter is connected to a data collection and processing control system. Each manometer tube is full of low conductivity buffer liquid and high conductivity manometric liquid. The resistance meter is configured to measure resistances in the one or more manometer tubes, and the data collection and processing control system is configured to convert the resistances measured by the resistance meter into a differential pressure.

A high pressure dynamic micro differential pressure gauge, and methods for using and checking the same. The high pressure dynamic micro differential pressure gauge comprises a set of vertical manometer tubes in communication with each other, where one or more manometer tubes are connected to a resistance meter through signal lines, and the resistance meter is connected to a data collection and processing control system. Each manometer tube is full of low conductivity buffer liquid and high conductivity manometric liquid. The resistance meter is configured to measure resistances in the one or more manometer tubes, and the data collection and processing control system is configured to convert the resistances measured by the resistance meter into a differential pressure.

A system for measuring electrical conductivity includes a fluid conduction measuring circuit and a temperature measuring element having at least one thermal contact portion with a temperature sensor and a temperature measuring circuit. A controller is configured to control the conduction measuring circuit and the temperature measuring element. A fluid circuit is configured to carry a fluid and has a wetted conductor inside a conductivity cell portion, the wetted conductor having a contact, external to the fluid circuit, for interfacing with the fluid conduction measuring circuit. Further, at least one temperature measurement portion has predefined thermal properties and is configured to touch the thermal contact portion. The controller controls the temperature measuring element and the conduction measuring circuit to generate and output at least one set of contemporaneous temperature and conduction measurements.

A shock detector having an electrical detector having a set of water immersible electrodes for detecting hazardous water conditions through the determination of the presence of either an electrical current in a body of water, a voltage in the body of water or a voltage gradient in the body of water and then providing an alert to the existence of hazardous electrical conditions in the body of water which in some cases may transmitted to a power source to shut off a power source thereby removing the hazardous water condition.

A shock detector having an electrical detector having a set of water immersible electrodes for detecting hazardous water conditions through the determination of the presence of either an electrical current in a body of water, a voltage in the body of water or a voltage gradient in the body of water and then providing an alert to the existence of hazardous electrical conditions in the body of water which in some cases may transmitted to a power source to shut off a power source thereby removing the hazardous water condition.

A method of measuring hematocrit and a method of testing blood are provided. The method for measuring hematocrit includes the following steps. A test strip is provided. The test strip includes a reaction region and a pair of electrodes disposed in the reaction region. A whole blood sample is entered to the reaction region. After the whole blood sample enters the reaction region, a set of square wave voltages is applied to the pair of electrodes based on a square wave voltammetry method to obtain a feedback related to hematocrit. A difference between an initial time when the whole blood sample enters the reaction region and an initial time when the set of square wave voltage is applied ranges from 0.1 seconds to 200 seconds. A hematocrit value is calculated according to the feedback.

A method of measuring hematocrit and a method of testing blood are provided. The method for measuring hematocrit includes the following steps. A test strip is provided. The test strip includes a reaction region and a pair of electrodes disposed in the reaction region. A whole blood sample is entered to the reaction region. After the whole blood sample enters the reaction region, a set of square wave voltages is applied to the pair of electrodes based on a square wave voltammetry method to obtain a feedback related to hematocrit. A difference between an initial time when the whole blood sample enters the reaction region and an initial time when the set of square wave voltage is applied ranges from 0.1 seconds to 200 seconds. A hematocrit value is calculated according to the feedback.

In order to avoid an electrode from disturbing a flow of a fluid in a flow channel in case that the electrode of an electric conductivity meter is arranged in the flow channel, the electric conductivity meter comprises two tubular electrodes inside of each of which respectively formed is an inner flow channel where the fluid flows, and an electrode holder that communicates each of the inner flow channels of the two electrodes and that holds the two electrodes. The electrode holder holds the two electrodes by making an engagement with each outer peripheral surface of mutually facing axial direction end parts of the two electrodes.

In order to avoid an electrode from disturbing a flow of a fluid in a flow channel in case that the electrode of an electric conductivity meter is arranged in the flow channel, the electric conductivity meter comprises two tubular electrodes inside of each of which respectively formed is an inner flow channel where the fluid flows, and an electrode holder that communicates each of the inner flow channels of the two electrodes and that holds the two electrodes. The electrode holder holds the two electrodes by making an engagement with each outer peripheral surface of mutually facing axial direction end parts of the two electrodes.