摘要:
An amorphous magnetic core is produced by wrapping cut strips of amorphous metal about a mandrel to form a distributed gap core. The cut strips are secured to the mandrel during assembly by wrapping the strips with amorphous metal ribbons that have been weakened in predetermined areas but not fully parted. After the core has been built to its desired size, the weakened ribbons are completely parted. This method of making an amorphous magnetic core produces a tightly wound distributed gap core without the need for a belt winder or specialized strip holding devices.
摘要:
A method and apparatus for manufacturing a variable insulated helically wound electrical coil is disclosed. Insulated rectangular wire is fed from a supply reel to a coating zone and within the coating zone liquid resin insulation is selectively applied to the wire so it has additional insulation only in those areas of the coil where the dielectric strength is needed. The insulated wire is fed through a curing station to allow curing of the additional insulation prior to winding the cured insulated wire into a coil. The cured insulated wire is wound into a coil of predetermined shape at a winding station whereby the portions of the wire having the additional insulatin are located in the areas of the coil where the greatest dielectric strength is needed. The timing of the resin application to the wire is coordinated with the winding of the coil so that the proper insulation thicknesses are achieved at the required locations in the coil. There is also disclosed a variably insulated helically wound high voltage electrical coil for a transformer wherein a variable thickness of cured synthetic resin insulation is applied to the turns in each layer of the coil so that the insulation increases in thickness from substantially zero at one end of the layer where layer-to-layer voltage stresses will be low and the required maximum thickness at the opposite end of the layer where voltage stresses will be high and this progression and insulation thickness is repeated on each adjacent layer of the coil.
摘要:
An electronic energy meter for use with a 3-wire delta service having a resistive voltage divider for sensing and scaling the line voltages is disclosed. The resistive voltage divider includes three resistive dividers, one being associated with each phase of the electrical energy being metered. Each resistive divider includes a current limiter for reducing the current into the meter to a safe level when the meter electronics are operating at an elevated level, and a resistor for scaling the line voltage to a predetermined maximum peak-to-peak value. The scaled voltage that is generated has minimal phase shift, and therefore, does not require phase shift compensation prior to processing by a processing system of the electronic meter.
摘要:
The stackable plastic cover allows a series of covers to be stacked into a column. This is achieved by increasing the sidewall taper to allow the inside of one cover to nest down over the outside of the adjacent cover. Conical projections on the outside of the tapered wall surface provide a stop for the adjacent cover to rest upon and additional conical projections are placed above the stops to prevent scratching of the covers and wall sections.
摘要:
An automated meter reading system is provided. The system includes a host server interfaced to a plurality of nodes where each node communicates with a number of utility meters. The system selects a group of noninterfering nodes and uses an RF broadcast from the host server to initiate the reading of meters and the uploading of meter data provided by those meters to the nodes and, ultimately, to the host server. The system also has a number of gateways that communicate with a plurality of nodes, grouped to form sets of noninterfering gateways. In this embodiment, the system selects a set of noninterfering gateways and uses an RF broadcast from the host server to initiate the reading of meters and the uploading of meter data provided by those meters to the nodes and, ultimately, through the gateways to the host server. A method for using an outbound RF channel to automatically read meters is also provided.
摘要:
A repeater communications module (RCM) that enhances signals in a communications network comprises a processor coupled to a communications medium and optionally to a host application. The RCM operates in one of two modes: (1) interface or host application controlled, and (2) standalone. In the interface mode, the RCM receives packets from a host application, modifies the packets and transmits message packets in accordance with a transmit role table (TRT). In standalone mode, the RCM initiates packets and transmits message packets in accordance with the TRT. All RCMs can be configured to repeat message packets which are received from the communications medium in accordance with a repeater role table (RRT).
摘要:
An apparatus and method for detecting tampering with an electrical energy meter comprising a disconnect switch, interposed into feeder lines that deliver electrical energy from a voltage source to an electrical load, which switches between an open circuit in which electrical energy is not supplied to the electrical load and a closed circuit in which electrical energy is supplied to the electrical load, a load-side voltage sensor, which provides voltage signals indicative of load-side voltage, and a microprocessor that determines whether a tamper conditions exists by determining whether the disconnect switch is open or closed, determining whether a load-side voltage is present, and, if the disconnect switch is open and a load-side voltage is present, indicating that a tamper condition exists. The tamper detection apparatus preferably includes a communications module, connected to the microprocessor, for providing a two-way communications interface to a remote location. In this embodiment, if the microprocessor determines that a tamper condition exists, the microprocessor transmits to the remote location a message indicating that a tamper condition exists. The communications module may also open or close the disconnect switch in response to open and close commands from the remote location. This feature permits remote polling of the meter to determine if a tamper condition is present.
摘要:
Methods and apparatus for establishing communications between electrical and electronic devices utilizing existing power signal distribution networks are disclosed. In such methods and apparatus the transmitting and receiving components of such devices are coupled between line and ground. Such coupling is achieved utilizing a coupler, a first frequency reactive device, such as a drain coil or inductor, connected in series with neutral and a second frequency reactive device, such as a capacitor connected between neutral ground. For use with existing electronic equipment, an adaptor for coupling the communications signal to a power signal distribution network is also disclosed. Since, line and neutral paths may sometimes be mis-wired, the apparatus and methods also disclose the use of a switch for enabling the coupling of a communication signal when a power signal is sensed on the line path.
摘要:
Colloidal fluids having improved insulating and/or cooling properties. Embodiments of the invention involve colloidal fluids which comprise a carrier liquid and a dispersed phase of non-metallic particles, wherein the colloidal fluid has a saturation magnetization of less than about 50 Gauss. The compositions may be employed to insulate and/or cool electromagnetic devices, including high power devices, such as power transformers.