A method includes computing electrical phase of electrical metering devices including obtaining data indicating zero-crossing times at first and second metering devices. A time difference between the zero-crossing times may be determined. In a first example, the time difference may be based at least in part on calculations involving a first value of a first free-run timer on a first metering device, a second value of a second free-run timer on a second metering device, the time of reception of a packet, and a latency defined by a time taken for the packet to propagate through at least one layer of at least one of the first metering device and the second metering device. A phase difference between the first zero-crossing and the second zero-crossing may be determined, based at least in part on the determined time difference.

The disclosure relates to a meter for monitoring usage of power provided by a power transmission system to a site. The meter comprises: a communication module to generate communications carried over the transmission system; a relay having a first position connecting power from the transmission system to the site and a second position disconnecting power; a request manager module to process messages from a head end associated with the transmission system; a meter module connected to a power feed associated with the transmission system to provide readings relating to the power used at the site; an event manager module to evaluate new events queued in a message queue received by the meter and after evaluating the new events to send a message to the head end relating to the earliest event in the message queue; a connection manager module managing the power connection to the transmission system.

This monitoring system for photovoltaic power generation includes: a first to n-th power collecting systems each for supplying a power conditioner with collected outputs from plural photovoltaic panels via a connection box; slave devices provided for connection boxes respectively belonging to the first to n-th power collecting systems, each slave device collecting measurement information about power generation and transmitting the collected measurement information by use of a direct current electrical path of the power collecting system thereof; a master device provided at a power collection end on an inlet side of the power conditioner to obtain the measurement information; a system selection unit for selecting one power collecting system upon reception of a selection signal from the master device and causing power line communication to be performed by use of a direct current electrical path of the selected power collecting system; and a monitoring device connected to the master device.

Aspects of the present disclosure are directed toward the use of broadcast transmissions to multiple endpoint devices. These broadcast transmissions can be particularly useful for reducing the communication bandwidth used during transmission of configuration data to the endpoint devices. In order to implement the broadcast communications, the present disclosure describes a mechanism for configuring targeted endpoint devices to be responsive to the broadcast communications. For instance, a configuration command can be sent to each of the targeted endpoint devices. The configuration command can include a virtual ID. The targeted endpoint devices can configure themselves to listen for subsequent broadcast messages addressed to the virtual ID. Configuration data can then be sent using the virtual ID and associated broadcast messages.

An electrical activity monitoring device based on a sensor device attachable to a power cable of an electrical device for monitoring the electrical status of the electrical device. The device comprises an antenna element which performs the dual functions of magnetically coupling with an electrical pulse generated in the power cable in response to a change of electrical power state of the electrical device and to transmit data to a reader via the power cable. An electrical activity monitoring apparatus is also provided for monitoring the electrical status of at least one electrical device connected to a power supply network by a respective power cable provided with a sensor device. The electrical activity monitoring apparatus comprises a reader and a reader-power line interface device.

Embodiments of this application disclose a method, an apparatus, and a system for information transmission in a PLC network. A switch control apparatus in embodiments of this application includes a switch and a coupling circuit. The coupling circuit is connected in parallel to two ends of the switch. When the switch is open, the coupling circuit transmits a first power line communication (PLC) signal to a gateway device. In embodiments of this application, when the switch is open, the PLC signal may be sent to the gateway device and information such as power off and tripping may be reported to the gateway device.

Embodiments of methods and systems for supporting coexistence of multiple technologies in a Power Line Communication (PLC) network are disclosed. A long coexistence preamble sequence may be transmitted by a device that has been forced to back off the PLC channel multiple times. The long coexistence sequence provides a way for the device to request channel access from devices on the channel using other technology. The device may transmit a data packet after transmitting the long coexistence preamble sequence. A network duty cycle time may also be defined as a maximum allowed duration for nodes of the same network to access the channel. When the network duty cycle time occurs, all nodes will back off the channel for a duty cycle extended inter frame space before transmitting again. The long coexistence preamble sequence and the network duty cycle time may be used together.

A method includes computing electrical phase of electrical metering devices including obtaining data indicating zero-crossing times at first and second metering devices. A time difference between the zero-crossing times may be determined. In a first example, the time difference may be based at least in part on calculations involving a first value of a first free-run timer on a first metering device, a second value of a second free-run timer on a second metering device, the time of reception of a packet, and a latency defined by a time taken for the packet to propagate through at least one layer of at least one of the first metering device and the second metering device. A phase difference between the first zero-crossing and the second zero-crossing may be determined, based at least in part on the determined time difference.

An embodiment method implemented by an agent device comprises receiving, by the agent device, from a device, a bootstrap request message over a first communication channel; transmitting, by the agent device, to a coordinating device, a request message comprising the bootstrap request message and a first channel type indicator indicating a channel type of the first communication channel; receiving, by the agent device, from the coordinating device, a response message comprising a bootstrap response message and a second channel type indicator indicating the channel type of the first communication channel; and transmitting, by the agent device, to a device, the bootstrap response message over a second communication channel in accordance with the second channel type indicator.

Selecting a communication route between a first and a second node device of a mesh electrical supply network using powerline and/or radio-frequency communications is described. A route cost is obtained for each possible communication route. A communication route of the lowest route cost is selected. For a given route, the route cost is the sum of the link costs between successive node devices on the route, the link cost between two successive node devices is a weighted sum between a maximum value from a link cost in a forward direction and a link cost in a backward direction and a ratio between a number of active routes and a maximum number of active routes. A link cost in a given direction depends on the cost of the link, in the given direction, calculated for each frequency band of frequency bands used by the two successive node devices for communicating.