Abstract:
An apparatus and method make use of a single shunt and two or more instrumentation amplifiers, switchably measuring voltages at the shunt. This permits current measurement. At times each instrumentation amplifier has its input shorted, which permits zeroing out many sources of offset in the signal path of that amplifier. Dynamic range is several orders of magnitude better than known current measurement approaches, permitting coulometry.
Abstract:
The present invention relates a method and apparatus for implementing a continuously ranging instrument for measuring small currents using an amplifier with negative or differential feedback and using a logarithmic-compression conversion technique.
Abstract:
A sensor assembly connected between a power line to be monitored and ground as a flexible lead assembly integrated with respective input and output ends as a single encapsulated flexible unit. A V-block (101) and screw clamp (109) are attached to an input circuit (102) which includes a current sensor coil (104) which generates an optical signal and transmits the sample data over a optical waveguide (105). This sample data is received by an output circuit (106) which is connected to ground through connector (107). Circuit (106) is also connected to a resistive element in the form of a resistor chain (103) which spirals around optical waveguides (105 and 110) and connects at the input end to circuit (102) which in turn connects to V-block (101) and thence to the line. The electronic circuits on circuit boards (102) and (106) sample and digitise the instantaneous value of this current from circuit board (102 to 106) over optical waveguide (105) along with the line current sample data. The optical signal(s) are converted to electrical form at the output end. Electronic circuitry on circuit board (106) processes the current and voltage sample data to derive information about the power line such as RMS current and voltage, power flow, power factor and so on and transmits this data in digital form to other equipment via external connector (107).
Abstract:
The force-loaded high-voltage lines (2) are interrupted electrically by a separator (3) which absorbs the forces in the lines. A current sensor arrangement (4) is electrically connected in parallel with the separator (3). The measuring signals are transmitted optically via a light guide (9) which is guided in a flexible insulator (6) at earth potential. The advantages afforded by the invention are a high level of safety with respect to earthquakes and good electrical isolation.
Abstract:
The present invention provides an electrical device for sensing both AC and DC current which is flowing through an electrical circuit regardless of operating frequency in the circuit. The electrical device includes conductive means for bifurcating the current into separate paths of fixed relationship to one another, wherein impedances of each path operate in a constant relationship to each other. In further embodiments of the invention, the electrical device includes current sensing means for measuring an output signal of the current flowing through the circuit, which is of a type which does not introduce an insertion loss into the circuit.
Abstract:
Die Erfindung betrifft eine Kupplung (6) zur elektrischen und mechanischen Verbindung von Komponenten der Mittelspannungstechnik oder der Hochspannungstechnik, insbesondere für Spannungen von 1 kV bis 52 kV, mit einem ersten Anschlussstück (8) zum mechanischen und elektrischen Anschluss einer Komponente der Mittelspannungstechnik oder der Hochspannungstechnik, insbesondere zum Anschluss an ein komplementäres Anschlussstück einer Durchführung eines Schaltschranks, und einem zweiten Anschlussstück (7) zum mechanischen und elektrischen Anschluss einer anderen Komponente der Mittelspannungstechnik oder der Hochspannungstechnik, insbesondere zum Anschluss an ein komplementäres Anschlussstück eines Elektrokabels, wobei die beiden Anschlussstücke (7, 8) der Kupplung (6) komplementären Anschlusstypen angehören, die mechanisch zusammen passen, sowie mit einem niederohmigen Strommesswiderstand (10, 11, 12), der baulich in die Kupplung (6) integriert ist und elektrisch zwischen das erste Anschlussstück (8) und das zweite Anschlussstück (7) geschaltet ist, um einen Stromfluss zwischen dem ersten Anschlussstück (8) und dem zweiten Anschlussstück (7) zu messen.