Abstract: Apparatus and methods are claimed for detecting tampering with a load management terminal, wherein the terminal has a load control relay coupled to a power line for selectably decoupling the load from the power line. One embodiment of the claimed apparatus for detecting tampering comprises a current sensor coupled to the load control relay for sensing whether load current is flowing through the load control relay contacts when the contacts are closed. A timer is provided for measuring elapsed time during which no current is sensed flowing through the closed contacts. An indicator provides an indication of tampering when the elapsed time measured by the timer exceeds a pre-determined time limit. Preferably, in this embodiment, the current sensor comprises a voltage detector coupled to the control coil of the relay for detecting whether an AC voltage has been induced in the control coil by the load current.

Abstract: A device for use in the testing of an optical probe which has at least one optical transmitter/receiver pair composed of one optical transmitter for emitting optical energy along a first path and one optical receiver for receiving optical energy propagated along a second path, the device including: a housing (4,6) formed to be mechanically coupled with the probe and having at least one pair of passages (14), with each passage (14) extending along a respective one of the first and second paths; and at least one optical energy reflecting member (18) disposed in the housing (4,6) and positioned relative to the passages (14) of the pair such that, when the housing (4,6) is coupled to the probe, light propagated along the first path from the transmitter is reflected by the reflecting member (18) into the second path toward the receiver.

Abstract: An electric meter is provided with a magnetically sensitive switch and a means for detecting the activation of the switch. A program is provided for sensing, recording and transmitting the status history of the magnetically sensitive switch to a remote device. The electric meter is connected in signal communication with a power line communication system and provided with the capability of transmitting and receiving messages in conjunction therewith. The electric meter senses the presence of a strong magnetic field in the region of the electric meter and, if other appropriate flags are not set, this information is used to determine that an effort to tamper with the meter by using magnetic fields has occurred.

Abstract: A transceiver is provided with a means for determining its own prescribed frequency upon the occurrence of an adverse transient condition, such as lightning, or upon initial installation after manufacture. Since it can safely be assumed that a transceiver's prescribe reception frequency is the same as its transmission frequency, the present invention measures the period of its transmission frequency in order to determine the frequency of its reception frequency. The exact frequency of incoming demodulated messages must be known in order for the transceiver's digital demodulator to properly demodulate the incoming signals. A high frequency signal, such as 1 mHz, is used to increment a pulse counter and the values of this pulse counter are stored upon the occurrence of two successive negative edges of the carrier signal.

Abstract: A field configuration terminal is provided that does not require physical or electrical connection to a remote device of a power line communication system. A toroid is provided that comprises a multiplicity of turns of a conductor that is connected in electrical communication with an amplifier and receiver circuitry within the field configuration terminal. A battery, with associated power supply components, provides a direct current source for the microprocessor and logic of the field configuration terminal and for the amplifier thereof. The toroid of the field configuration terminal is shaped to be disposed around a load management terminal of a power line communication system without physical or electrical contact therewith. Signals are transmitted to and received from the load management terminal by inductively coupling the toroid with the load management terminal in signal communication.

Abstract: A watt-hour meter tamper detector characterized by a fiber optic link that extends between a microprocessor of a load management terminal and mounting means for maintaining a watt-hour meter cover intact, and which fiber optic link signals an attempted opening of the mounting ring to the microprocessor when the fiber optic link is severed.

Abstract: A load management terminal is utilized as an end device in a utility's distribution network communication system. The distribution network carries electrical power as well as communication signals. The load management terminal is comprised of a power line coupling unit for connecting the load management terminal to the power distribution network. A signal receiver and conditioning unit produces a command signal in response to a received communication signal. A solid state memory contains preprogrammed instructions and data. A microprocessor performs load control functions in response to the command signal. The microprocessor additionally produces a diagnostic signal being in a low state in response to one of the preprogrammed instructions and being in a high state in response to another of the preprogrammed instructions.

Abstract: A load management terminal is utilized as an end device in a utility's distribution network communication system. The distribution network carries electrical power as well as communication signals. The load management terminal is comprised of a power line coupling unit for connecting the load management terminal to the power distribution network. A signal receiver and conditioning unit produces a command signal in response to a received communication signal. A solid state memory contains preprogrammed instructions and data. A control logic circuit performs load control functions in response to the preprogrammed instructions, data and the command signal. These load control functions include the opening and closing of load control switches for selectively disconnecting and connecting, respectively, customer loads. A cold load pick-up produces power outage information enabling the load management terminal to provide local, load control functions.