Modular Electrical Accessory

Abstract

A modular electrical accessory for a building has a housing for attaching to a building structure and an electrical backplane mounted in the housing. The electrical backplane is configured to be electrically wired to an electrical circuit associated with the building. A user-replaceable electrical accessory module is removably connectable by a user to an electrical bus and a control bus of the modular electrical accessory. The electrical bus enables transfer of electrical power between a connected user-replaceable electrical accessory module and the electrical backplane, while the control bus enables control signals to be communicated between a connected user-replaceable electrical accessory module and the electrical backplane for controlling delivery of electrical power to an electrical device based on the control signals

Claims

1. A modular electrical accessory for a building, the modular electrical accessory comprising: a housing for attaching to a building structure; an electrical backplane mounted in the housing, the electrical backplane configured to be electrically wired to an electrical circuit associated with the building; an electrical bus and a control bus removably connectable to a user-replaceable electrical accessory module by a user; wherein the electrical bus is configured to transfer electrical power between a connected user-replaceable electrical accessory module and the electrical backplane; and the control bus is configured to communicate control signals between a connected user-replaceable electrical accessory module and the electrical backplane for controlling delivery of electrical power to an electrical device based on the control signals.

2. The modular electrical accessory of claim 1, wherein the user-replaceable electrical accessory module is interchangeable by the user between: a module to control the operation of an electrical device; and a module having an outlet connectable to an electrical device to provide electrical and/or data services to the electrical device.

3. (canceled)

4. The modular electrical accessory of claim 1, wherein an electrical device is connected to the electrical bus and the user-replaceable electrical accessory module controls delivery of electrical power to the electrical bus based on control signals from the control bus in order to control the operation of the electrical device, wherein the electrical bus receives electrical power from the electrical circuit via the electrical backplane.

5. (canceled)

6. The modular electrical accessory of claim 4, wherein the user-replaceable electrical accessory module comprises an electrical outlet connectable to an electrical device, wherein the electrical outlet is configured to provide electrical power to the electrical device from the electrical bus.

7. The modular electrical accessory of claim 6, wherein the outlet comprises a low voltage electrical outlet and/or an extra-low voltage electrical outlet.

8. (canceled)

9. The modular electrical accessory of claim 1, wherein the modular electrical accessory further comprises a transceiver powered by electrical power received from the electrical bus, wherein the transceiver is configured to communicate data with an external device, and the user-replaceable electrical accessory module further comprises an outlet connectable to an electrical device, wherein the outlet is configured to communicate the data with the electrical device.

10. (canceled)

11. The modular electrical accessory of claim 1, where the modular electrical accessory has an interface configured to receive a desired state of operation of an electrical device.

12. The modular electrical accessory of claim 11, wherein the interface comprises a user interface configured to receive input from a user indicating a desired state of operation of an electrical device, for example, one or more of: a toggle switch; one or more push button switches; a dimmer switch; a touch panel; a speech recognition processor; a motion sensor; and a variable controller.

13. The modular electrical accessory of claim 11, further comprising a wired or wireless communications interface configured to communicate the desired state of operation between the communications interface and an external device, for example, one or more of: an external electronic device; a bridge; and a further modular electrical accessory.

14. (canceled)

15. The modular electrical accessory of claim 11, wherein the interface is interchangeable by the user between interfaces of different types.

16. The modular electrical accessory of claim 11, wherein the interface is configured to control delivery of electrical power to an electrical device connected to the electrical bus, wherein the control bus is configured to communicate control signals from the interface for controlling delivery of electrical power by the electrical bus to the electrical device based on the control signals, wherein the interface is configured to output control signals on the control bus indicative of the desired state of operation of the electrical device.

17. (canceled)

18. The modular electrical accessory of claim 1, wherein the electrical backplane further comprises a wired or wireless communications interface configured to communicate control signals between the control bus and an external device.

19. The modular electrical accessory of claim 1, further comprising a control component configured to: receive control signals from the control bus; and control delivery of electrical power by the electrical bus to the electrical device based on the control signals received from the control bus.

20. (canceled)

21. (canceled)

22. The modular electrical accessory of claim 1, further comprising: a plurality of user-replaceable electrical accessory modules configured to receive electrical power from the electrical bus and communicate control signals on the control bus, wherein the control signals further comprise a unique identifier associated with a selected user-replaceable electrical accessory module, and a control component configured to deliver power to the selected user-replaceable electrical accessory module in response to the control signals comprising the unique identifier associated with the selected user-replaceable electrical accessory module.

23. The modular electrical accessory of claim 1, wherein the user-replaceable electrical accessory module and the electrical backplane are electrically connected by one or more interconnects.

24. (canceled)

25. The modular electrical accessory of claim 1, wherein the housing is an electrical backbox for mounting to a building structure.

26. The modular electrical accessory of claim 1, further comprising a securing means configured to secure the user-replaceable electrical accessory module to the housing, optionally wherein the securing means is a faceplate configured to secure the user-replaceable electrical accessory module to the housing.

27. A system comprising a modular electrical accessory in communication with a further modular electrical accessory, wherein: the modular electrical accessory comprises: a user-replaceable electrical accessory module removably connectable to a communication interface in the modular electrical accessory by a control bus for communicating control signals between the user-replaceable electrical accessory module and the communication interface, wherein the user-replaceable electrical accessory module comprises a user interface configured to receive a desired state of operation of an electrical device connected to the further electrical accessory module and communicate the desired state of operation as control signals on the control bus; wherein the communication interface is configured to receive the control signal from the control bus and send the control signal indicating the desired state of operation to the further modular electrical accessory; and the further modular electrical accessory comprises: an electrical bus and a further control bus removably connectable to a further user-replaceable electrical accessory module, wherein the electrical bus is configured to transfer electrical power to the further user-replaceable electrical accessory module and the further control bus is configured to communicate control signals to the further user-replaceable electrical accessory module; a further communication interface configured to receive the control signals from the modular electrical accessory and communicate the control signals on the further control bus to the further user-replaceable electrical accessory module; wherein the further user-replaceable electrical accessory module comprises a control component configured to control the supply of electrical power to the electrical device connected to the electrical bus based on the control signal received on the further control bus.

28. The system of claim 27, wherein the modular electrical accessory is installable at a first location in a building and the further modular electrical accessory is installable at a second location in the building remote from the first location.

29. (canceled)

30. (canceled)

31. A user-replaceable electrical accessory module removably connectable by a user to an electrical bus and a control bus of a modular electrical accessory according to claim 1.

32. (canceled)

33. (canceled)

34. (canceled)

35. (canceled)

36. (canceled)

37. (canceled)

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0069] The invention shall now be described, by way of example only, with reference to the accompanying drawings, in which:

[0070] FIG. 1 illustrates a prior art electrical accessory;

[0071] FIG. 2 illustrates a prior art two-way switch;

[0072] FIG. 3 illustrates an exploded three-dimensional view of a modular electrical accessory according to an embodiment of the invention;

[0073] FIG. 4 is an exploded cross-sectional side view of the modular electrical accessory of FIG. 3;

[0074] FIG. 5 illustrates electrical connections between a user-replaceable electrical accessory module and an electrical backplane;

[0075] FIG. 6 is a block diagram showing electrical outlets of the user-replaceable electrical accessory module;

[0076] FIG. 7 illustrates the modular electrical accessory controlling an external device;

[0077] FIG. 8 illustrates an external device controlling the modular electrical accessory; and

[0078] FIG. 9 illustrates a first electrical accessory module controlling a device connected to a second electrical accessory module.

DETAILED DESCRIPTION

[0079] Conventional electrical accessories (such as light switches and mains electrical sockets) have a faceplate with a front side having sockets and/or switches accessible to a user during normal use and a rear side with terminals for making permanent electrical connections (for example, to a mains electricity supply) usually by screwing or crimping electrical cables to the terminals. Making any changes to these conventional electrical accessories (such as changing a toggle switch for a dimmer switch, or changing a mains electrical socket for one having extra-low voltage outlets, such as USB sockets, for providing extra-low voltage power to portable electronic devices) requires these electrical connections to be disconnected and reconnected which, as mains voltages are involved, usually requires the services of a qualified electrician.

[0080] Specialist electrical accessories are available which provide multimedia connections in addition to mains power. These are typically mounted in a wall adjacent to where a television might be located, to provide electrical power and multimedia connections to the television. FIG. 1 shows an example of such an electrical accessory 100 which offers audio-visual ports 110 (e.g. HDMI, VGA, etc), a network port 120 configured to provide an ethernet internet connection, one or more USB data ports 130, an audio port 140 (such as a headphone jack), and a mains electrical socket 150. Whilst the electrical accessory 100 provides a convenient “all-in-one” product to connect and power a number of different peripherals from a single unit, electrical connections must again be made to terminals associated with each port on the rear side of the faceplate. Even in cases where the individual ports are modular and can be changed to suit an individual user’s requirements, it is still necessary to modify hardwired connections to terminals associated with each individual port.

[0081] It is often desirable in a building to provide a way to control a light or other electrical device from several different locations, such as from either end of a corridor or from the top and bottom of stairs. FIG. 2 shows an example of a conventional two-way switching arrangement 200 which is used to control a light bulb 220 from two different locations in a building. In this example, the light bulb 220 can be controlled by a first light switch 230 at the bottom of a flight of stairs 250 and a second light switch 240 at the top of the flight of stairs 250. This allows a user to turn the light bulb 220 on to illuminate the stairs 250 before negotiating the stairs 250 in either direction, and turn the light bulb 220 off afterwards. In this conventional arrangement, a substantial amount of cabling must be run between the light bulb 220 and the switches 230 and 240. This makes it difficult to add a new two-way light switch where one was not present previously and makes it more difficult to make changes such as moving the location of any of the components since any changes incur the cost of repairing damage to the walls and ceilings when running new cables.

[0082] FIG. 3 is an exploded three dimensional view of a modular electrical accessory 300 according to the present invention which seeks to overcome the shortcomings with existing electrical accessories. The modular electrical accessory 300 has a housing such as a backbox 310 for recessing into a building structure (such as a wall, floor, or ceiling), although other housings might be surface mounted as desired.

[0083] The modular electrical accessory 300 has an electrical backplane 320 mounted within the backbox 320. The electrical backplane 320 has terminals 322 that can be hardwired to an electrical circuit of the building by a qualified electrician. The electrical circuit may be a low voltage electrical circuit (such as a mains electrical circuit), an extra-low voltage electrical circuit (such as a 12 V or 5 V electrical circuit), a lighting circuit (including a conventional manual direct switching lighting circuit and a bus controlled lighting circuit, like DALI), a communications, data or multimedia circuit. In this example, the modular electrical accessory 300 includes buttons 332 and therefore the terminals 322 of the electrical backplane 320 might be hardwired to an electrical device which is to be controlled by these buttons (such as one or more light bulbs).

[0084] The user-replaceable electrical accessory module 330, can easily be inserted into and removed from the backplane 320 by a user, without any electrical knowledge whatsoever and without the need for a qualified electrician. The user-replaceable electrical accessory module 330 and the electrical backplane 320 are coupled by interconnects which transfer electricity and optionally control signals between the user-replaceable electrical accessory 330 module and the electrical backplane 320.

[0085] In this example, the interconnectors are provided by pins 331 on the user-replaceable electrical accessory module 330 which couple with corresponding recessed terminals 321 in the electrical backplane 320. The use of pins 331 and recessed terminals 321 may protect the user from exposure to mains voltages. The shape of the module and/or the pins may be keyed to ensure correct alignment. Instead of pins 331 and terminal 321, any other kind of interconnects or connectors could be used for transferring electricity and/or control signals between the user-replaceable electrical accessory module 330 and the electrical backplane 320, For example, control signals need not require a direct electrical connection and could be transferred by a wireless (radio-frequency), optical, or near field communications link instead.

[0086] As a result, the user-replaceable electrical accessory module 330 may be swapped by the user, for example, to allow the user to change the user-replaceable electrical accessory module 330 if it becomes faulty or should they wish to change its functionality (such as swapping the buttons shown in FIG. 3 for a rotary dial), without the need for a qualified electrician. As soon as the user-replaceable electrical accessory module 330 is connected to the electrical backplane 320, the user-replaceable electrical accessory module 330 is connected into the electrical circuit to the light bulb via the backplane 330, without the need to modify the wiring to the terminals 322.

[0087] FIG. 4 is an exploded cross-sectional side-view of the modular electrical accessory 300 to show the internal components.

[0088] The housing 310 is recessed into a cut-out in a wall 412 of a building. Cable 414 is buried in the wall. The cable 414 forms at least part of an electrical circuit which provides electrical power to the modular electrical accessory 300 and connects the modular electrical accessory 300 to a light bulb 420 that is controllable by the buttons 332.

[0089] Cables 414 are fed through an opening in the housing 310 and electrically connected to terminals 322 on the electrical backplane 320. The electrical backplane 320 is positioned within the housing 310.

[0090] The user replaceable electrical accessory 330 is shown connected to the electrical backplane 320, and a faceplate 440 (not shown in FIG. 3 for clarity purposes) is positioned over the user-replaceable electrical accessory module 330. The faceplate 440 comprises a cut-out section to accommodate the buttons 332 of the user-replaceable electrical accessory module 330 (shown by dashed lines in FIG. 4). The faceplate 440 is attached to the housing 310 (for example, with screws or clips) to secure the user-replaceable electrical accessory in place (shown by dashed arrows in FIG. 4) and prevent unintentional removal.

[0091] The user-replaceable electrical accessory module 330 has an electrical bus 434 connected between the user-replaceable electrical accessory module 330 and the electrical backplane 320. The terminals 322 terminating cables 414 are connected to the electrical bus 434, such that the electrical supply to the light bulb 420 is connected to the electrical bus 434 via cables 414. A switching component 437 in the user-replaceable electrical accessory module 330 controls the flow of power on the electrical bus 434 to the light bulb 420 according to user input at buttons 332.

[0092] Pressing buttons 332 causes the processor 438 in the user-replaceable electrical accessory module 330 to generate a control signal on a control bus 436. The switching component 437 is connected to the control bus 436 and the control signal causes the switching component to selectively couple electrical power to the light bulb 320 over the electrical bus 434 depending on the control signal.

[0093] The control bus 436 is also connected between the user-replaceable electrical accessory module 330 and the electrical backplane 320, in order to transfer control signals between the user-replaceable electrical accessory module and a processor 450 in the electrical backplane 320. As will be discussed in more detail in FIGS. 7, 8 and 9, this allows the control signals to be sent to and from the user-replaceable electrical accessory module 330 to control other electrical devices, to allow the user-replaceable electrical accessory module to be controlled by other electrical devices, or to allow remote control of other user-replaceable electrical accessory modules. In this example, the control bus 436 is shown as a wired connection between the user-replaceable electrical accessory module 330 and the electrical backplane 320, but a wireless connection (such as RF, optical or near-field) could be used instead.

[0094] FIG. 5 is a diagram illustrating how the user-replaceable electrical accessory module 330 is electrically connected to the electrical backplane 320. The user-replaceable electrical accessory module has two sets of connectors comprising pins 512 on the user-replaceable electrical accessory module and corresponding terminals 522 to receive the pins 512 on the electrical backplane 320. The upper set of pins connects the control bus 436 and the lower set of pins connects the electrical bus 434. However, the upper set of pins for the control bus 436 could be omitted if the user-replaceable electrical accessory module 330 and electrical backplane 320 were connected by a wireless connection.

[0095] Also shown in FIG. 5 is an enlarged view 524 of one terminal 522, where electrical contact 526 is shown recessed within terminal 522 of electrical backplane 320, in order to protect a user from exposure to the mains supply voltage received from the electrical circuit 414.

[0096] The user-replaceable electrical accessory module 330 could be swapped by the user for a different user-replaceable electrical accessory module having different controls (for example, swapping the push buttons 332 shown in FIG. 3 for a rotary dial). Alternatively, the user-replaceable electrical accessory module 330 could be swapped for a different user-replaceable electrical module providing different functionality. For example, if a light switch module is no longer required at a particular location, the light switch module may be swapped for an electrical outlet which may draw its electrical power from the electrical circuit which provides electrical power to the modular electrical accessory 300.

[0097] FIG. 6 shows an alternative example of a user-replaceable electrical accessory module 630 with a mains electrical outlet 662 for supplying mains electrical power to an electrical device connected to the electrical outlet 662 and an extra-low voltage electrical outlet in the form of USB socket 664 for supplying an extra-low voltage (such as 5V) to a portable electrical device (such as a smartphone).

[0098] The mains electrical outlet 662 receives mains electrical power from the electrical bus 434.

[0099] The USB socket 664 receives extra-low voltage from the electrical bus 434 (where the transformer is in the electrical backplane 320), or a transformer in the user-replaceable electrical accessory module 330 converts the mains electrical power from the electrical bus 434 into an extra-low voltages supply for the USB socket 664.

[0100] Other user-replaceable electrical accessory modules with different arrangements of electrical outlets are available, for example, user-replaceable electrical accessory modules with just a low voltage outlet or outlets (such as a mains outlet or outlets) and others with just an extra-low voltages outlet (or outlet). This allows a user to easily swap a low voltage outlet (such as a mains outlet) for an extra-low voltage outlet by simply swapping the user-replaceable electrical accessory module, without the need for any rewiring, electrical qualifications or indeed any specialist electrical knowledge. This may be advantageous if the standard for extra-low voltage outlets changes in the future (for example, from USB outlets prevalent today to something else), as it would allow the outdated outlets to be replaced for modern outlets without the need for rewiring and with a minimum of waste.

[0101] The outlets may also be easily replaced for other kinds of outlets as well, such as media or network outlets, where the media or network data may be provided over the control bus 436 from a wired or wireless communications link to the electrical backplane 320.

[0102] FIG. 7 illustrates how the modular electrical accessory 300 can control an external device 774.

[0103] As discussed in relation to FIG. 4, pressing buttons 332 on the user-replaceable electrical accessory module 330 causes the processor 438 in the user-replaceable electrical accessory module 330 to generate a control signal on the control bus 436. However, rather than these control signals causing switching component 437 to couple electrical power over the electrical bus 434 to a device directly wired to the electrical bus 434 (such as the light bulb 320 in FIG. 4), the control signals on the control bus may additionally or alternatively be sent to an external device 774 to control the external device 774 remotely.

[0104] For example, first and second light switches may be located at opposite ends of a hallway for controlling a single light bulb, so that the light bulb can be turned on/off from either end of the hallway. However, only the second light switch may be electrically wired to the light bulb with the first light switch sending wireless control signals to control the light bulb via the second light switch when a user presses buttons on the first light switch. For example, when the user presses an on button on the first light switch, the first light switch sends a control signal to the second light switch instructing the second light switch to couple electrical power to the light bulb to turn it on.

[0105] The control bus 436 is connected between the user-replaceable electrical accessory module 330 and the electrical backplane 320, in order to transfer control signals between the user-replaceable electrical accessory module and the processor 450 in the electrical backplane 320.

[0106] The processor 450 receives the control signals from the control bus 436 and the processor 450 transmits these control signals to external device 774 using wireless transceiver 772. Since there may be more than one external device, the control signals include a unique identifier which allows the external devices to determine whether the control signals are meant for them. The control signal causes the external device 774 to be controlled according to the button presses, for example, turning the external device 774 on/off.

[0107] The external device need not be local to the user-replaceable electrical accessory module 330 that is controlling it. That is, the external device could be in a remote location such as a different building and the control signals may be transmitted over a wired or wireless network (including over the internet) to the remote location. For example, the external device might be a light in an outbuilding and the user-replaceable electrical accessory module may be a light switch located in the main building for remotely turning on/off the light in the outbuilding.

[0108] As shown in FIG. 8, the external device may also control the user-replaceable electrical accessory module 330, to allow for remote control of an electrical device connected to the user-replaceable electrical accessory module.

[0109] The external device 774 send a control signal including a unique identifier that identifies the user-replaceable electrical accessory module 330 the control signal is intended for. The wireless transceiver 772 receives the control signal and the processor 450 passes the control signal to the control bus 436 where the processor 438 in the user-replaceable electrical accessory module determines that the unique identifier associated with the control signal indicates that the control signal is intended for the user-replaceable electrical accessory module 330 and the processor 438 instructs the switching component 437 to selectively provide electrical power on the electrical bus 434 to control the light bulb 420 according to the instructions of the external device 774.

[0110] The external device 774 need not be local to the user-replaceable electrical accessory module 330 that it is controlling. That is, the external device 774 could be in a remote location such as a different building and the control signals may be transmitted over a wired and/or wireless network (including over the internet) to the user-replaceable electrical accessory module 330. For example, the external device might be a smartphone and the user-replaceable electrical accessory module may be a light switch located in a house, and the smartphone can be used to remotely turn on/off the light from outside the house.

[0111] FIG. 9 illustrates an example of a system 800 where a first electrical accessory module 810 may control a light bulb 820 (or other electrical device) connected to a second electrical accessory module 830 that may be remote from the first electrical accessory module 810.

[0112] A user presses a button 812 on the first electrical accessory module 810 to indicate a desired state (on/off) of the light bulb 820. Pressing the button 812 generates a control signal indicating the desired state of the light bulb 820, for example in the manner discussed in relation to FIGS. 4, 7 and 8. A communications interface 814 sends the control signal, either directly to the second electrical accessory module 810 (peer-to-peer) or via a bridge 840 which retransmits the signal to the second electrical accessory module 830. Either way, the second electrical accessory module 830 has a second communication interface 832 that receives the control signal 816 from the first electrical accessory module 810, and selectively controls the power to the light bulb 820 according to the desired state as discussed in FIG. 4.

[0113] The bridge 840 may be connected to a wide area network (such as the internet) via a wired or wireless connection, to allow any of the electrical accessory modules, such as the first and second electrical accessory modules 810, 830, to be controlled and monitored remotely.

[0114] This example could be used to implement a two-way switch where a light bulb 820 may be controlled from either ends of a corridor, or from both the bottom and top of a flight of stairs.

[0115] This example can also be used to assist in reconfiguring the location of controls for electrical device (such as switches for lights) and electrical outlets in a building without any rewiring. Each of the electrical devices (such as lights and electrical outlets) in a building can be hardwired during building construction or refurbishment to a control panel, typically located in a service area of the building. The control panel is essentially a modular electrical accessory, such as the modular electrical accessory 300, but on a larger scale since it can house enough electrical accessory modules so that one can be wired to each of the electrical devices in the building.

[0116] A property developer may install modular electrical accessories around the building and wire them into an electrical circuit to provide them with power, but leave the user-replaceable electrical accessory modules either blank so that the homeowner or tenant can decide how to populate them, or with a limited number of generic switches and outlets to perform basic functions. A homeowner or tenant is then free to augment or modify the arrangement of user-replaceable electrical accessories modules to suit their needs, for example, to control any of the electrical devices in the building from whatever locations suits them best. The user-replaceable electrical accessory modules the homeowner or tenant installs are then programmed to communicate with the electrical accessory modules in the control panel to control the desired electrical device without any physical alternations to the building’s wiring being required. This makes it very easy to change the location of light switches, for example, to suit changes in occupant or room layout without requiring rewiring or the services of a qualified electrician.

[0117] Although the invention has been described in terms of certain embodiments, the skilled person will appreciate that various modifications could be made which would still fall within the scope of the claimed invention.

[0118] The user-replaceable electrical accessory module 330 has been described as including buttons 332 as an example control component to enable a user to control an electrical devices connected to the user-replaceable electrical accessory module 330. The buttons 332 may be in the form of a toggle switch, a push button switch, a rotary dial, a touch screen or a touch panel. In a further example, the control component may be a variable controller. The variable controller may be a dimmer switch to control the brightness of a light bulb connected to the electrical circuit. The variable controller may be a volume control to adjust playback volume of a sound system in communication with the modular electrical accessory. As a further example, the variable controller may be a temperature control to adjust the temperature of a heating device (for example a radiator) in communication with the modular electrical accessory.

[0119] Instead of buttons 332, the user-replaceable electrical accessory module 330 may alternatively or additionally include other control components to allow the user to control an electrical device connected to the user-replaceable electrical accessory module 330. For example, the user-replaceable electrical accessory module may include a motion sensor (such as a PIR sensor) configured to detect the movement of a user within a particular zone of the building and control the electrical device based on the movement of the user (for example, turning a light connected to the module on if movement is detected). Alternatively or additionally, a speech recognition processor may control the electric device according to voice commands, for example a voice command to turn on the light bulbs in a particular room or rooms of the building. An eye-gaze sensor may detect and track a user’s eye gaze to control the electrical device connected to the user-replaceable electrical accessory module 330.

[0120] Swapping the user-replaceable electrical accessory for a new one with a different user interface (such as swapping a conventional toggle switch with a PIR sensor) makes it very straightforward for a user to tailor the way electrical devices in the building are operated, even if these requirements were not envisaged at the time the building was configured. This provides flexibility to change and upgrade the configuration over time as technology develops or needs change.

[0121] For example, the user-replaceable electrical accessory module 330 may be a module which has been specifically tailored to the needs of particular users, such as those with disabilities or the elderly, allowing their needs to be met by simply switching the user-replaceable electrical accessory module 330 to one best suited to their needs, as often as is necessary, without the need for any rewiring. For example, the user-replaceable electrical accessory module 330 may be a touch module with tactile feedback, a switch with braille symbols, a switch with large buttons which are easy to press, or a switch controlled by speech, a motion sensor (such as a PIR sensor) or a user’s eye gaze.

[0122] In the above examples, the electrical device connected to and controlled by the user-replaceable modular electrical accessory has been shown as a light bulb. However, the electrical device could instead be another electrical device, such as, one or more peripheral external electrical devices, a central heating system, a sound system, a doorbell, an extractor fan, or any other suitable electrical device.

[0123] The outlet may additionally or alternatively include a multimedia outlet for supplying media data to a device connected to the multimedia outlet. In another example, the electrical outlet may include a network outlet for communicating network data with the electrical device connected to the network outlet. The multimedia outlet and network outlet may communicate data from the wireless transceiver in the electrical backplane over the control bus.

[0124] The wireless transceiver 772 has been described as being in the electrical backplane 320. However, a wireless transceiver 772 could be provided in the or each user-replaceable electrical accessory module 330, thereby eliminating the need for the control bus 436.