Abstract: A meter for monitoring consumption of a resource, such as water or other fluids, and corresponding methods of configuring and operating the meter are disclosed. The meter includes processing and memory devices for determining and storing a supplier measure of consumption of the resource and a communication link for enabling a supplier to access the stored supplier measure. The supplier access is controlled by a first access control device, which prevents unauthorized access to the stored data. The meter further includes a consumer data memory for storing consumer data including a consumer measure of consumption and second access control device. The second access control device enables a consumer to access the stored consumer data without permitting the consumer to modify the stored supplier measure of consumption.

Abstract: A method of obtaining a measure of flow from an electromagnetic flow meter is disclosed. A shaped excitation waveform is applied to the flow meter and an output is received from the meter. The sampled output data from the meter is then resolved into a non-flow waveform component and a flow waveform component to derive a measure of flow. Resolving the data into expected waveform components rather than correlating each frequency component of the sampled output data with a sine wave may allow readings to be obtained without processing each frequency component separately. Also, the method may allow more accurate removal of the non-flow component from the output signal, and may decrease the time delay before the initial reading and allow the use of a greater reading repetition rate.

Abstract: There is described herein a method of obtaining a measure of flow from an electromagnetic flow meter having at least one field generating coil and potential sensing electrodes. A composite excitation waveform is applied to the field-generating coil. The composite excitation waveform comprises at least two frequency components and a plurality of frequency components are simultaneously present for at least a portion of the waveform. The potential sensed by the potential sensing electrodes is sampled to produce a sampled output and the sampled output is correlated with a composite waveform based on the composite excitation waveform. The result of the correlating is used to derive a measure of flow.

Abstract: In order to reduce the influence of fluid velocity on a measurement of a concentration characteristic of a fluid, the magnitude of an r.m.s. signal V derived from a voltage induced in a sensor provided in relation to the fluid passage is adjusted using a factor dependent upon the measured velocity v of the fluid. Consequently, the accuracy with which the mass flow rate M of the solids in the fluid can be determined is improved.

Abstract: A previously unidentified problem of clipping in the input stages of flowmeter sensing circuitry has been identified and addressed. A solution is provided by flowmeter sensing circuitry, comprising: first and second inputs for connection to potential sensing electrodes positioned to measure a potential difference across the fluid which potential is representative of flow; differential amplifier means coupled to the first and second inputs for producing an output signal indicative of said potential difference across the fluid as a measure of flow; characterized by at least one voltage sensing means for sensing a voltage of at least one of the first and second inputs relative to a ground reference; and fault detecting means for detecting a potential fault if the voltage is outside a predetermined range.

Abstract: In a vibrating tube meter such as a Coriolis meter, an accurate measurement of a fluid parameter such as density can be obtained, substantially independent of stress, by measuring vibrational characteristics, particular resonant frequencies of two different vibrational modes. Stress or other variables can be determined from the measurement. Because the measurement of or compensation for stress is based directly on the vibrational characteristics, better accuracy may be obtained than by using a conventional strain gauge to measure stress. The techniques disclosed can give accurate results without requiring particular constraints on meter design.

Abstract: A microbial membrane reactor for use in flow systems comprises a first element to receive the microorganisms and a second element to receive the flow channels. The two elements have planar interior surfaces which are pressed together separated by a membrane impervious to the microorganisms. The flow channels arranged in or on the surface of the second element serve to transport the liquid along the membrane so that the liquid can interact with the microorganisms arranged on the other side of the membrane. The geometry of the flow pathway and thus the geometry of the flow channels can be easily altered, in respect of the length, width and height of the channel, and adapted to practical requirements.

Abstract: An apparatus analyzes liquid samples automatically and continuously by mixing certain reagents within a common arrangement of membrane pumps, mixing chambers and connecting conduits formed in a silicon wafer and evaluating the reaction results with the help of suitable sensors on the silicon wafer, the silicon wafer being of 100 orientation and the structure thereof having been formed by anisotropic etching. Immediately before and after the pump chamber of trapezoidal cross section, there are conduits of a v-shaped or trapezoidal cross section which have a nonlinear flow resistance.