TECHNICAL FIELD OF THE DISCLOSURE

The present disclosure is in the field of electricity meters for metering of electricity consumption, such as in residential and commercial premises. The disclosure relates to a metering apparatus for installation in a cabinet. In particular, the disclosure relates to wireless communications with a metering apparatus installed in a secure cabinet.

BACKGROUND

Centralized electricity meters may be implemented to combat energy theft in high-risk areas. In a centralized electricity meter, one or more electricity meters for metering consumption of electrical power at a premises may be disposed within a secure cabinet, which may be located external to the premises.

In an example, such a secure cabinet may be mounted on a utility pole and may be generally out of convenient reach of vandals or thieves, which may minimise a likelihood of tampering and/or theft. In other examples, a secure cabinet may be based at ground level.

Electricity meters within the cabinet may be in wireless communication with corresponding remote display modules located at the premises to which electrical power is supplied. As such, electrical power consumption information may be relayed to the remote display modules from the corresponding electricity meters.

In this manner, an electricity meter itself need not be disposed at the premises, minimising a likelihood of tampering with the electricity meter.

Even with such centralized electricity metering systems, electricity meters may be prone to vandalism and fraudulent actions, e.g. electricity theft. To further combat this, the cabinet enclosing the electricity meters may be made extremely secure and robust. In some instances, the cabinet may be tamperproof, and even bulletproof, and may have a metallic casing.

A metallic casing may act as a Faraday shield to the electricity meters enclosed within the cabinet. This may effectively limit wireless communication capabilities with electricity meters disposed within the cabinet. As such, it may be necessary to implement multiple antennas on an exterior of the cabinet, along with associated complex circuity to enable wireless communication with electricity meters disposed within the cabinet.

However, such complex circuity may be expensive to implement, may be prone to damage and faults and eventual failure in the field. The provision of multiple antennas may attract acts of vandalism, and may provide multiple means to access an interior of the cabinet.

It is therefore desirable to provide a low-cost, low complexity and highly reliable means for implementing a centralized electricity meter. It is desirable that such means support reliable wireless communication with the electricity meters enclosed within the cabinet, yet remains highly tamper- and vandal-proof.

It is therefore an aim of at least one embodiment of at least one aspect of the present disclosure to obviate or at least mitigate at least one of the above identified shortcomings of the prior art.

SUMMARY

The present disclosure is in the field of electricity meters for metering of electricity consumption, such as in residential and commercial premises. The disclosure relates to a metering apparatus for installation in a cabinet. In particular, the disclosure relates to wireless communications with a metering apparatus installed in a secure cabinet providing restricted access.

According to a first aspect of the disclosure, there is provided a metering apparatus for installation in a cabinet. The apparatus comprises a plurality of electricity meters for metering electricity consumption. The apparatus comprises a plurality of communications devices. Each communications device is coupled to an associated at least one of the plurality of electricity meters. The apparatus comprises a signal splitter configured to couple to each communications device to an antenna.

Advantageously, use of signal splitter may mitigate a requirement to implement an active repeater, as described in the prior art solutions below. The signal splitter may be cheaper than an active repeater, and may improve an overall reliability of the apparatus.

Advantageously, use of signal splitter may allow implementation of only a single antenna for communication by all of the communications devices. A single antenna may reduce overall system costs, and be also make the overall apparatus less susceptible to theft or vandalism.

Advantageously, a signal splitter may allow reuse of existing electricity meters without substantial modification or adaptation. As such, existing electricity meters that have already been certified for use may be used in the disclosed apparatus.

The signal splitter may comprise a passive RF signal splitter/combiner.

Advantageously, a passive device requires no dedicated power supply, and is therefore inherently cheaper and more reliable to implement. The signal splitter may be configured for use with conducted RF (Radio Frequency) signals, e.g. signals ranging from around 20kHz to 300GHz. As a non-limiting example, the signal splitter may be suitable for RF signals in the 900 MHz range.

The signal splitter may comprise a splitter/combiner. That is, the signal splitter may also be known in the art as an ‘RF Power divider' or ‘RF Power Splitter’ or ‘RF Power combiner’ or ‘RF splitter/combiner’. That is, the signal splitter may be configured for both combining and for dividing or splitting signals.

The signal splitter, e.g. the passive RF signal splitter/combiner, may be configured to combine signals from each communications device for transmission by the antenna.

Advantageously, a plurality of communications devices may be configured to communicate over a single antenna using the passive RF signal splitter/combiner. As a non-limiting example, in embodiments described in more detail below four communications devices are connected to a single antenna by a 4:1 signal splitter.

The passive RF signal splitter/combiner may be configured to split signals received by the antenna for reception by one or more communications devices of the plurality of communications devices.

Advantageously, a single antenna may receive signals from a mesh network directed to a plurality of communications devices, wherein each communications devices operates as an individual node on the mesh network.

The communications devices may be configured to communicate, via the antenna, to form a wireless mesh network with one or more further communications devices.

Advantageously, the splitter enables each communications devices to directly join the mesh network as an individual node, rather than having to form an internal mesh network within the cabinet, as described in more detail below with regard to the prior art apparatus of Figure 1 . The communications devices may be configured to communicate, via the antenna, to provide direct communication between each electricity meter and an associated wireless display device.

Advantageously, through use of the signal splitter, the same antenna that may be used for forming the mesh network using the plurality of communications devices as individual node may also be used for enabling direct communication between electricity meters and associated wireless display devices, rather than having to use an active RF repeater to perform this function as described in more detail below with reference to Figure 1.

Each communications device may be conductively coupled to the signal splitter.

In an example embodiment, each communications device and/or the antenna may be coupled to the signal splitter by a coaxial cable. The signal splitter may comprise connectors, such as SMA connectors, suitable for coupling to each coaxial cable. As such, each communications device may be directly coupled to the antenna. An advantage of the using the signal splitter is that a mesh network outside the secure cabinet may effectively see communications devices as if they were in individual cabinets, since all their communications are effectively externalized via the antenna. That is, the prior art solution without the splitter need to use one communications device as "parent", which creates an additional layer to the mesh network.

Each communications device may be conductively coupled to the associated at least one of the plurality of electricity meters.

The metering apparatus may comprise a plurality of chassis. Each communications device and the associated at least one of the plurality of electricity meters are arranged on a respective chassis of the plurality of chassis.

Advantageously, subsets of electricity meters may be provided in a chassis that may be electrically isolated from another chassis comprising a subset of electricity meters within the cabinet.

The metering apparatus may comprise a plurality of signal splitters and an antenna associated with each signal splitter. Each signal splitter may be configured to couple an associated plurality of communications devices to the associated antenna.

For example, in some embodiments a large quantity of chassis may be provided, requiring implementation of more than one signal splitter and associated antenna.

According to a second aspect of the disclosure, there is provided an arrangement comprising the metering apparatus of the first aspect in combination with the cabinet. At least a portion of the antenna may be disposed, e.g. may extend, outside the cabinet. In some embodiments, the antenna may be the sole antenna extending from the cabinet. A reduction in a number of antennas extending from the cabinet may reduce a susceptibility of the cabinet to vandalism.

The cabinet may comprise a metallic casing. The metallic casing may enclose the plurality of electricity meters, the plurality of communications devices and the signal splitter.

In addition to providing robustness, a metallic casing cabinet may act as a Faraday shield, inhibiting unwanted interference with the electricity meters within the cabinet.

The cabinet may be configured as a secure cabinet providing restricted access to the metering apparatus.

Access to an interior of the cabinet may be prevent by a locking means. The cabinet may be designed to be tamperproof, and in some embodiments bulletproof.

According to a third aspect of the disclosure, there is provided an electricity metering system. The electricity metering system comprises the arrangement according to the second aspect. The electricity metering system comprises at least one wireless display device disposed outside the cabinet and configured to communicate directly, via the antenna, with an associated electricity meter of the plurality of electricity meters.

The electricity metering system may comprise a plurality of the arrangements according to the second aspect.

One or more communications devices in one of the plurality of arrangements may be configured to form a wireless mesh network with one or more communications devices in at least one other of the plurality of the arrangements.

The above summary is intended to be merely exemplary and non-limiting. The disclosure includes one or more corresponding aspects, embodiments or features in isolation or in various combinations whether or not specifically stated (including claimed) in that combination or in isolation. It should be understood that features defined above in accordance with any aspect of the present disclosure or below relating to any specific embodiment of the disclosure may be utilized, either alone or in combination with any other defined feature, in any other aspect or embodiment or to form a further aspect or embodiment of the disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS These and other aspects of the present disclosure will now be described, by way of example only, with reference to the accompanying drawings, wherein:

Figure 1 depicts a prior art electricity metering system, showing electricity meters disposed within a cabinet; and

Figure 2 depicts an electricity metering system according to an embodiment of the disclosure.

DETAILED DESCRIPTION OF THE DRAWINGS

Figure 1 depicts a block diagram of a prior art electricity metering system 100.

The system comprises a cabinet 105. The cabinet 105 may be provided as a robust, secure cabinet 105, such as a lockable cabinet. The cabinet 105 may be known in the art as a “Safe Box”. In an example use case, the cabinet 105 may be mounted on a pole, such as a utility pole that may be used to support overhead power lines. In other examples the cabinet 105 may be mounted at ground level, such as on a plinth.

The cabinet 105 encloses a metering apparatus. The metering apparatus comprises a plurality of electricity meters 110a, 110b, 110c, 110d for metering electricity consumption. That is, each electricity meter 110a, 110b, 110c, 110d may be configured to meter a consumption of electrical power by a load at an associated premises.

In the prior art electricity metering system 100, the metering apparatus comprises a plurality of chassis (not shown). The electricity meters 110a, 110b, 110c, 110d are arranged in groups on each chassis. For purposes of example, four groups are depicted, and twelve electricity meters 110a, 110b, 110c, 110d are arranged on each chassis, denoted “Meter Module 1 ... 12” in each group in Figure 1.

Each chassis has an associated communications device 120a, 120b, 120c, 120d, denoted ‘Radio’ in Figure 1 . Also depicted is processing circuitry 125a, 125b, 125c, 125d. In some embodiment, the processing circuitry 125a, 125b, 125c, 125d may be configured for processing data read from each associated electricity meter 110a, 110b, 110c, 110d and for controlling and/or establishing communications by each communications device 120a, 120b, 120c, 120d.

A first communications device 120a is directly coupled to a first antenna 130. The first antenna 130 extends outside the cabinet 105. As such, the first antenna 130 enables communications between the first communications device 120a and one or more remote devices located outside the cabinet 105, as described in more detail below. Second communication devices 120b, third communication devices 120c and fourth communication devices 120d are not directly, conductively connected to the first antenna 130. Instead, communication with each of the second, third and fourth communication devices 120b, 120c, 120d may be established by wireless communication with the first communication device 120a within the cabinet 105, as described below.

A second antenna 135 is provided. The second antenna extends outside the cabinet 105.

Also depicted is a plurality of wireless display devices 140 disposed outside the cabinet 105 and configured to communicate, via a second antenna 135 and a respective communication device 120a, 120b, 120c, 120d, with an associated electricity meter of the plurality of electricity meters 110a, 110b, 110c, 110d. In examples, communication device 120a communicates with its respective remote display modules using antenna 130. In order for the remote display repeater to be able to actually repeat packets from a specific communication module, e.g. radio, this communication device 120a needs to be specifically configured for that purpose, and only devices 120b, 120c and 120d are configured in that way. As such, communication devices 120b, 120c and 120d communicate with their respective display modules using repeater module 145 and antenna 135. Communications device 120a communicates with its remote display modules directly using antenna 130. Exceptionally, communications device 120a may use its own antenna 130 to communicate also to its associated wireless display device. The other communications devices (120b, 120c and 120d) uses the antenna 135 to communicate with their wireless remote devices.

A repeater module 145, which may comprises a dedicated communications device, e.g. a radio, is provided inside the cabinet 105 and coupled to the second antenna 135. In an example, the repeater module 145 may be configured to repeat wireless signals provided from each electricity meter 110b, 110c, 110d, via associated communication devices 120b, 120c, 120d, to the plurality of wireless display devices 140 disposed outside the cabinet 105. That is, the second antenna 135 enables communications between each electricity meter 110a, 110b, 110c, 110d and an associated wireless display device 140.

Operation of the prior art electricity metering system 100 is as follows.

In use, the first communications device 120a is configured, e.g. coupled to the external antenna 130, to join the mesh network with other communications devices that may be disposed outside the cabinet 105. For purposes of illustration only, the portion of the mesh network outside the cabinet 105 is hereafter referred to as the external mesh network 175. The external mesh network 175 is denoted “external” because it is external to the metallic cabinet 105. Said other communications devices may comprise other electricity metering systems that may be within range of the present electricity metering system. Other communications devices may comprise collector device 155, which may be gateway device or router that may act as a backhaul device to the external mesh network 175.

However, due to the metallic cabinet 105 effectively acting as an RF shield, the second communications device 120b, third communications device 120c and fourth communications device 120d are unable to directly join the mesh network 175. As such, the first, second third and fourth communications devices 120a, 120b, 120c, 120d form an internal RF mesh-network within the cabinet 105. The internal mesh network is denoted “internal” because it is internal to the metallic cabinet 105. The internal mesh is, in effect, an extension of the external mesh network 175. All communications between the second, third and fourth communications devices 120b, 120c, 120d in the internal mesh network and the external mesh network 175 must be routed via the first communications device 120a.

In this prior art example, the second, third and fourth communications devices 120b, 120c, 120d have their antennas removed replaced with terminating 50 Ohm RF terminations 150b, 150c, 150d, wherein in a non-limiting example each RF termination 150b, 150c, 150d may be implemented using one or more impedances, e.g. resistors or the like. The RF attenuation caused by the RF terminations 150b, 150c, 150d enables only sufficient RF transmission for formation of the internal mesh network within the cabinet 105, and the second, third and fourth communications devices 120b, 120c, 120d are unable to directly communicate wirelessly with the external mesh network 175. That is, the second, third and fourth communications devices 120b, 120c, 120d which have their antennas removed and RF terminations fitted effectively use the first communications devices 120a as a “parent” node to enable communication to the external RF mesh network 175.

The repeater module 145 is configured to maintain communication with the remote wireless display devices 140 vie the second antenna 135 to provide respective meter consumption information to the wireless display device 140. As an example, it may be a requirement for the wireless display devices 140 to receive respective meter consumption information periodically, such as once a minute, to comply with commercial regulations or industry standards. The prior art electricity metering system 100 presents several problems.

For example, it is necessary to install the first antenna 130 and the second antenna 135, along with the repeater module 145 and associated modified firmware, which all contributes to an overall cost and complexity of the electricity metering system 100, and may be detrimental to the reliability of the electricity metering system 100.

Furthermore, having multiple antennas 130, 135 may increase a vulnerability of the electricity metering system 100 to damage or vandalism.

Furthermore, the prior art electricity metering system 100 provides limited performance with field tools 160, such as tools for debug, analysis repair or maintenance of the electricity metering system 100. This is because a communication range with the second, third and fourth communications devices 120b, 120c, 120d is extremely reduced due to the 50 Ohm RF terminations install on their respective SMA ports instead of antennas. A field tool 160 is only able to wireless connect directly to the first communications device 120a, and does not have direct wireless communication with the second, third and fourth communications devices 120b, 120c, 120d. Practically, it may be necessary for a field tool 160 to be located within approximately 30 centimetres of the electricity metering system 100, with the cabinet 105 door open, to establish direct wireless communication with any of the second, third and fourth communications devices 120b, 120c, 120d. This may not be practically feasible, especially with a utility polemounted cabinet 105.

Figure 2 depicts an electricity metering system 200 according to an embodiment of the disclosure.

The system comprises a cabinet 205. The cabinet 205 may be provided as a robust, secure cabinet 205, such as the above-described “Safe Box”. In an example use case, the cabinet 205 may be mounted on a pole, such as a utility pole. In other examples the cabinet 205 may be mounted at ground level, such as on a plinth.

The cabinet 205 encloses a metering apparatus. The metering apparatus comprises a plurality of electricity meters 210a, 210b, 210c, 21 Od for metering electricity consumption. That is, each electricity meter 210a, 210b, 210c, 21 Od may be configured to meter a consumption of electrical power by a load at an associated premises.

The metering apparatus comprises a plurality of chassis. The electricity meters 210a, 210b, 210c, 21 Od are arranged in groups on each chassis. For purposes of example only, four groups are depicted, and twelve electricity meters 210a, 210b, 210c, 21 Od are arranged on each chassis, denoted “Meter Module 1 ... 12” in each group in Figure 2. Each chassis has an associated communications device 220a, 220b, 220c, 220d, denoted ‘Radio’ in Figure 1 . Also depicted is processing circuitry 225a, 225b, 225c, 225d. The processing circuitry 225a, 225b, 225c, 225d may be configured for processing data read from each associated electricity meter 210a, 210b, 210c, 21 Od and for controlling and/or establishing communications by each communications device 220a, 220b, 220c, 220d.

In contrast to the prior art electricity metering system 100, all of the first, second, third and fourth communications devices 220a, 220b, 220c, 220d are coupled to a signal splitter 270. The signal splitter 270 is directly coupled to an antenna 230. As such, the signal splitter is configured to couple to each communications device 220a, 220b, 220c, 220d to the antenna 230.

The first, second, third and fourth communications devices 220a, 220b, 220c, 220d are conductively coupled to the signal splitter 270. In the example of Figure 2, the first, second, third and fourth communications devices 220a, 220b, 220c, 220d are conductively coupled to the signal splitter 270 by coaxial cables 280a, 280b, 280c, 280c. In example embodiments, such coaxial cables 280a, 280b, 280c, 280c may be coupled to the signal splitter 270 and to the communications devices 220a, 220b, 220c, 220d by SMA connectors.

The signal splitter 270 is a passive RF signal splitter/combiner. The signal splitter 270 may be configured for both combining and for dividing or splitting signals. That is, the signal splitter 270 may act as both a signal splitter and a signal combiner.

The signal splitter 270 is configured to combine signals from each communications device 220a, 220b, 220c, 220d for transmission by the antenna 230.

The signal splitter 270 is also configured to split signals received by the antenna 230 for reception by one or more of the communications devices 220a, 220b, 220c, 220d. As such, all of the communications devices 220a, 220b, 220c, 220d can be used to directly communicate on a network external to the cabinet using the antenna 230. That is, the antenna 230 which extends outside the cabinet 205 enables communications between all of the communications devices 220a, 220b, 220c, 220d and one or more remote devices located outside the cabinet 205, as described in more detail below.

Also depicted is a plurality of wireless display devices 240 disposed outside the cabinet 205 and configured to communicate directly, via the antenna 230 and a respective communications device 220a, 220b, 220c, 220d, with an associated electricity meter of the plurality of electricity meters 210a, 210b, 210c, 21 Od.

Operation of the electricity metering system 200 is as follows. In use, each communications device 220a, 220b, 220c, 220d is configured to directly, wirelessly join an external mesh network 275 with other communications devices that may be disposed outside the cabinet 205. The external mesh network 275 is denoted “external” because it is external to the metallic cabinet 205. Said other communications devices may comprise other electricity metering systems that may be within range of the present electricity metering system. Other communications devices may comprise collector device 255, which may be gateway device or router that may act as a backhaul device to the external mesh network 275. In contrast to the prior art electricity metering system 100, it is not necessary for each communications device 220a, 220b, 220c, 220d to form an internal mesh network within the cabinet. Each communications device 220a, 220b, 220c, 220d has effectively has its communications externalized from the cabinet by the single antenna 230.

The electricity metering system 200 is substantially simplified relative to the prior art electricity metering system 100. Instead of using a repeater module 145 with its own radio and a dedicated external antenna 135 in addition to an external antenna 130 for communication with the external mesh-network 175, the disclosed electricity metering system 200 used a signal splitter, e.g. a passive RF power splitter, to connect all of the communication devices 220a, 220b, 220c, 220d directly to a single external antenna 230 connected to a sum port of the signal splitter, thereby mitigating a requirement for an additional external antenna and a repeater module. This ensures that all communications devices 220a, 220b, 220c, 220d have direct, wireless, RF communication outside the cabinet 205, for both communication with the mesh network 275 and also for communication with the wireless display devices 240.

In a non-limiting example use case, the communication devices 220a, 220b, 220c, 220d may each act as a node on the external mesh network 275, which may operating using frequency-hopping spread spectrum communications. Communications with the wireless display devices 240 may be single-channel communications, wherein each wireless display device 240 is paired with an associated electricity meter 210a, 210b, 210c, 21 Od. A selection of channel may be based, for example, on a serial number of the wireless display device 240. Communications via the single antenna 230 with both the external mesh network 275 and the wireless display devices 240 may be at frequencies in the region of 900MHz.

Although the example embodiment of Figure 2 depicts a single 4:1 signal splitter 270 coupled to four communications devices 220a, 220b, 220c, 220d and an single antenna 230, it will be understood that other configurations fall within the scope of the disclosure. For example, in embodiments the system may comprise a plurality of signal splitters and an antenna associated with each signal splitter, wherein each signal splitter is configured to couple an associated plurality of communications devices to the associated antenna.

The disclosed electricity metering system 200 provides several benefits.

Installation of only a single antenna 230 and removal of the repeater module 145 along with associated circuitry, power supplies, surge protection and isolation requirements, may substantially reduce an overall cost and complexity of the electricity metering system 200, and may improve an overall reliability of the electricity metering system 200.

Furthermore, having only a single antenna 230 may decrease a vulnerability of the electricity metering system 200 to damage or vandalism.

Furthermore, the electricity metering system 200 provides improved performance with field tools 260, such as a tool for debug, analysis repair or maintenance of the electricity metering system 200. A field tool 160 is able to wirelessly, connect directly to the all of the first, second, third and fourth communications devices 220a, 220b, 220c, 220d without need to open a door of the cabinet's 205. That is, the field tool 260 are cable of communicating with all communications devices 220a, 220b, 220c, 220d without having the need to open the door of the cabinet 205 because all of the communications devices 220a, 220b, 220c, 220d have direct communication to the external environment by using the signal splitter 270 and the antenna 230. This facilitates field operation and maintenance of the system 200.

Although the disclosure has been described in terms of particular embodiments as set forth above, it should be understood that these embodiments are illustrative only and that the claims are not limited to those embodiments. Those skilled in the art will be able to make modifications and alternatives in view of the disclosure, which are contemplated as falling within the scope of the appended claims. Each feature disclosed or illustrated in the present specification may be incorporated in any embodiments, whether alone or in any appropriate combination with any other feature disclosed or illustrated herein. LIST OF REFERENCE NUMERALS

100 electricity metering system

105 cabinet

110a-d electricity meters

120a-d communications devices

125a-d processing circuitry

130 first antenna

135 second antenna

140 wireless display devices

145 repeater module

150b-d RF terminations

155 collector device

160 field tool

175 external mesh-network

200 electricity metering system

205 cabinet

210a-d electricity meters

220a-d communications devices

225a-d processing circuitry

230 antenna

240 wireless display devices

255 collector device

260 field tool

270 signal splitter

275 mesh network

280a-d coaxial cables