GB2488027A

GB2488027A - Electrical socket allowing testing

Info

Publication number: GB2488027A
Application number: GB201202006A
Authority: GB
Inventors: Stephen Finch; Simon Bagshaw; Daniel Slack
Original assignee: Individual
Current assignee: Individual
Priority date: 2011-02-10
Filing date: 2012-02-06
Publication date: 2012-08-15
Also published as: GB201202006D0; GB201102362D0

Abstract

An electrical socket includes a front part 2 and a back part. The front part has a socket for a plug. Electrical connection means are provided on or associated with the back part for connecting an electrical supply and/or one or more electrical connectors. The front part is selectively detachable from the back part in use without disconnecting the back part and/or the electrical connection means provided on or associated with the back part, allowing the socket to be tested. The connection means may include a switch or other isolation means, and the isolation means may prevent the front part being fitted to the back part when the switch is open. The front part may be attached to the back part with quick release connectors 66.

Description

I

Electrical Socket and Method of Use Thereof The invention to which this application relates is an electrical socket and a method of use thereof.

Although the following description refers almost exclusively to an &ectrical wall socket as may be used for receiving a plug of a conventional electrical appliance, it will be appreciated by persons skilled in the art that the present invention can be used for receiving other types of electrical connections and/or can be a non-wall mounted socket.

A conventional electrical wall socket typically comprises a back plate or box 100 that is inserted into a complementary shaped recess in the wall 102 and secured in place, and a front plate 104 that is attached to the back plate in use, as shown in figures 6a- 6c. One or more electrical wires 106 from a mains electrical supply, typically located in the wall 102, are inserted through one or more apertures defined in the back plate 100 for connection to the front plate 104. The front plate 104 typically comprises a plurality of apertures 108 on a front surface 110 thereof for the location of a plurality of complementary shaped pins of a conventional electrical plug therethrough in use.

Electrical connection means 112 are provided at the rear 114 of the front plate 104 and the electrical wires are joined to the electrical connection means 112 of the front plate 104. As such, when the pins of an electrical plug are inserted through the apertures of the front plate, electrical connection can be made between the mains electricity supply and an electrical appliance to which the electrical plug is attached.

In the field of commercial and domestic electrical installations there is an increasing need to develop testing procedures to ensure that installations are fit for purpose'. The development of devices for the isolation of the power supply in the event of an issue arising in a given installation relies upon the intervention speed of the device to protect the individual and also the installation itself. Consequently, a number of procedures have been developed by the Institute of Electrical Engineers to permit the inspection of installations (i) prior to the commencement of full operations and (ii) periodically thereafter. One such procedure is the hard wiring examination' which is mandatory on all new installations and is frequently an insurance requirement in older commercial facilities.

The procedure for checking the hard wiring, in any facility, currently requires that the wiring connections for the last in line' socket are disconnected in order to measure the resistance and continuity between each end of the ring main, and potentially at other sockets on the ring main in the event that a fault is detected and consequently needs to be traced, so as to ensure that the system is operationally safe and that reaction times for specific breakers are not exceeded. In addition, a visual inspection is required for each outlet.

This procedure is not only extremely time consuming and costly to carry out, but also has the disadvantage that since connections have to be broken and subsequently re-made, it is impossible to be certain that the system is not compromised as a result of the inspection.

In addition, the current design of electrical sockets and switches requires that all wiring connections are made to the front plate of each device which is subsequently pushed into place prior to tightening up the fitting into engagement with the back plate or box. However this leads to a further disadvantage as during the pushing in and tightening up process' the potential for the wiring to be compromised is significant.

An aim of the present invention is to provide an electrical socket which can meet the testing requirements without the need for the original connections to be broken.

A further aim of the present invention is to provide an electrical socket where the potential for damage to either the connections or the cable itself as a result of the testing procedure is minimised.

A yet further aim of the present invention is to provide a method of using an electrical socket for testing purposes.

In an aspect of the invention there is provided electrical socket, said electrical socket including a front part and a back part, said front part including one or more apertures for the location of one or more pins of an electrical plug therethrough in use, said electrical socket further including electrical connection means for connecting an electrical supply and/or one or more electrical connectors to the pins of the electrical plug in use, and wherein the electrical connection means are provided on or associated with the back part and the front part is selectively detachable from the back part in use without requiring disconnection of the back part and/or the electrical connection means provided on or associated with the back part.

Thus, the present invention provides an arrangement that is opposite to the prior art electrical socket arrangement. In the present invention, the electrical connection means are provided on or associated with the back part of the electrical socket only, such that the front part of the electrical socket can be completely detached and re-attached as often as required without disturbing the electrical wiring, mains electrical supply and/or electrical connectors associated when the back part of the socket. As such, hard wiring testing can be undertaken simply by completely removing the front plate of the socket without the need to break and remake electrical contacts. In addition, since the electrical connection means are associated with the back plate, a visual inspection of the electrical connection means can be undertaken without having to disconnect any electrical connection means. Furthermore, there is no requirement to push wiring or electrical connection means back into the back part in order to re-fit the front part thereto once an inspection and/or testing has been completed.

In one embodiment it can be seen that the front plate is acting as a "blind plate" in that it is simply acting as a cover plate for the socket, in contrast to the prior art where the front plate typically has the electrical connection means provided thereon or associated therewith.

In one embodiment the back part includes a housing for fitment in or to a support surface. Typically the support surface is a wall, floor or ceiling. Thus, in one embodiment the electrical socket of the present invention is a wall, floor or ceiling mountable electrical socket.

In one embodiment, when the back part is fitted in or to a support surface, the front part is selectively detachable from the back part without disconnecting the back part from the support surface or electricity connectors.

In one embodiment the electrical connection means include one or more mains electricity terminals. The mains electricity supply is typically carried along one or more electrical wires that are located in a wall of the facility and the end of the wires form or are attached to the mains electricity terminals in the socket in use.

In one embodiment, the electrical connection means provided on or associated with the back part includes a live electrical connector, a neutral electrical connector and an earth electrical connector. Preferably the electrical connection means are provided in one or more sets, each set of electrical connectors comprise three connectors; a live, a neutral, and an earth electrical connector.

In one embodiment the electrical connection means provided on or associated with the back part include one or more electrical contacts for receiving and/or contacting one or more pins of an electrical plug of an electrical appliance inserted through the apertures of the front part in use. Typically the electrical contacts of the back part are in electrical communication with the electrical connectors of the back part.

Typically the one or more apertures provided on the front part are located in a position or positions corresponding or substantially aligned to the positions of the electrical contacts on or associated with the back part to allow direct contact to be made between the pins of the electrical plug and the electrical contacts in use.

In one embodiment one or more groups or sets of three apertures are provided on the front part of the electrical socket.

The groups or sets of apertures typically correspond to the groups or sets of electrical connectors provided on or associated with the back part. Preferably a group of three apertures correspond to three pins of an electrical plug in the UK.

In one embodiment one set of electrical connectors is provided for a single electrical socket; two sets of electrical connectors are provided for two electrical sockets or a double electrical socket, and/or a third set of electrical connectors is provided for a spur.

In one embodiment isolation means are provided on or associated with the back part of the socket. Preferably the isolation means electrically isolate two or more components or electrical components of the socket from each other. The isolation means preferably electrically isolates the one or more electrical contacts, the electrical connection means and/or electrical connectors.

In one embodiment the isolation means includes switching means. Preferably the isolation means and/or switching means comprises one or more electrical switches which can be selectively moved between a closed position and an open position for respective electrical connection and disconnection thereby. The switches are provided on or associated with the back part of the socket.

In one embodiment the electrical switches include one or more side-by-side or adjacent mountable terminals.

In one embodiment the electrical connection means and/or each electrical connector is associated with a switch. In a further embodiment each type (i.e. live, neutral and/or earth) of electrical connector is associated with a switch. In a yet further, one switch is provided for all the electrical connectors or a set or group of electrical connectors within a socket. It is to be noted that there switches are separate and independent to any switch provided on or associated with the front part of the socket to move the socket between "on" and "off" operational conditions.

In one embodiment the back part is provided with testing means to allow a user to test an electrical circuit in use (i.e. in which the socket forms a part thereof). Typically the testing means include one or more screws securing the electrical connectors in position on or in association with the back part.

Thus, shorting between the screws allows the electrical circuit to be tested. The electrical socket according to the invention allows a test to be performed between isolation means and/or a switch in the electrical socket and the ring main without disconnecting the electrical connectors from the back part and/or front part of the electrical socket.

In one embodiment the isolation means and/or one or more switches prevent attachment of the front part to the back part when one or more switches are in the open position. Typically the isolation means and/or one or more switches extend outwardly of the back part towards the front part when in the open position to physically prevent the front and back parts coming together to form an electrical socket in use. This is a safety feature such that isolation means and/or the switches have to be moved to a closed position in order for the first part to be attached to the back part of the socket.

In one embodiment a plate is provided to cover the isolation means and/or switches. Typically at least part of the plate is substantially clear or transparent to allow visual inspection of the socket, switch and/or internal connections by a user. Thus, in one embodiment the plate can be an intermediate plate located between the front and back parts of the socket and/or is a plate attached to the back plate.

In one embodiment the plate is formed as part of the front part.

Thus a user can visually examine the electrical connections of the back part without removing the front part from the back part.

In one embodiment the front part is attachable to the back part via quick-release means, such as for example, one or more quick release connectors. Thus the testing procedure can be hastened as less time is spent in removing the required components for access.

Preferably the front part is moved from a first locked or attached position, wherein the front part is securely fastened to the back plate to form an electrical socket, to a second unlocked or detached position, wherein the front part can be completely removed from the back plate. The electrical connections of the electrical socket and the back part are completely undisturbed in moving the front part from the attached to the detached positions.

In one embodiment the electrical socket is formed as part of a consumer unit i.e. the main fuse board. It will be appreciated that only two sets of electrical connectors are typically connected to the consumer unit.

Preferably isolation means are provided in the consumer unit.

Preferably the isolation means electrically isolates two or more components or electrical components of the consumer unit and ring main to which the consumer unit is typically attached to in use. This allows electrical continuity testing to be carried out between the consumer unit and one or more electrical sockets forming part of the ring main.

In one embodiment the electrical connection means are provided on an intermediate part or internal block which is integral with, attached or detachably attached to the back part. The intermediate part or internal block is typically located between the front and back parts when the front part is in the attached position. Any or any combination of the isolation means, one or more switches, mains electricity terminals, electrical connectors and one or more electrical contacts can be provided on the intermediate part or internal block as required.

The intermediate part or the internal block can be attached or detachably attached to the back part via any suitable attachment means, such as one or more bolts, screws, quick release means, clips, friction fit, inter-engaging members, welding, adhesive and/or the like.

The back part can be attached to the supporting surface via any suitable attachment means, such as one or more bolts, screws, quick release means, clips, friction fit, inter-engaging members, welding, adhesive and/or the like.

Securing means, such as one or more retaining bars, clamping means, channels, recesses and/or the like can be used to secure one or more wires and/or cables in position within the socket as required.

According to one aspect of the present invention there is provided a method of using the electrical socket.

In a further aspect of the invention there is provided a method of testing an electrical socket, said electrical socket including a front part and a back part, said front part including one or more apertures for the location of one or more pins of an electrical plug therethrough in use, said electrical socket further including electrical connection means for connecting an electricity supply and/or one or more electrical connectors to the pins of the electrical plug in use, said method including the steps of: -removing the front part of the electrical socket to reveal the back part with electrical connection means provided on or associated with the back part, the front part being detached without disconnecting the back part and/or the electrical connection means provided on or associated with the back part; and -testing the electrical socket.

Preferably the front part is reattached to the back part once the testing has been completed.

Preferably the electrical connection means include one or more electrical contacts for receiving and/or contacting the pins of the plug in use and said testing step involves electrically isolating the electrical connectors from the electrical contacts.

In one embodiment the testing step may include isolating the ring mains and/or distribution board prior to testing the electrical socket. Typically the ring mains and/or distribution board are reconnected after testing the electrical socket.

In one embodiment the user actuates switching means to electrically isolate the electrical connectors from the electrical contacts during the testing step.

Specific embodiments of the invention are now described wherein: -Figure 1 illustrates a schematic view of a front part of an electrical socket in accordance with an embodiment of the invention.

Figure 2 illustrates a schematic view of a portion of the back part of the electrical socket of Figure 1.

Figure 3 illustrates a schematic view of a further portion of the back part of the electrical socket of Figure 1: (a) internal block; (b) switching means.

Figure 4 illustrates a schematic view of switching means according to the invention (a) in an electrical socket (b) in a consumer unit.

Figure 5 illustrates how the electrical socket of Figure 1 is fitted (a) wall ready to receive socket; (b) wall receiving back box; (c) back box secured; (d) internal block fitted to back box; (e) front part being secured to back part.

Figures 6a-c illustrate the different stages of fitting a conventional electrical supply to a front plate of a wall socket.

Figures 7a and 7b illustrate a prior art consumer unit and a consumer unit according to the present invention respectively.

With reference to Figure 1, there is illustrated the front part 2 of an electrical socket, which includes a plurality of apertures 4 through which the pins of an appliance's plug may be inserted.

The apertures have spring-loaded shutters to prevent ingress of dirt or accidental access by other items.

In this example two appliance plugs may be received in the socket, and electrical power is supplied to the appliance by actuating the appropriate operational switches extending through slots 6 on the front part.

The front part 2 is secured to a back part (not shown) by quick release fixings 8, as used on aircraft, which push in to secure and simply turn through 90 degrees to release.

The electrical socket is connected to the electrical connectors of a ring main 10 as will be described later.

With regard to Figure 2, the housing 12 of the back part is illustrated in the form of a plastic wall back-box. The housing may be fixed to a wall using screws in a conventional manner via holes 14, and the ring main 10 is secured to the housing with a securing strip 16.

The ring main includes electrical connectors in the form of a live wire 18, an earth wire 20 and a neutral wire 22. The earth wire may be electrically connected to the earth connector 24 as illustrated in figure 3a.

The housing includes internally threaded fixing points 26 for alignment of the power outlet mechanism i.e. the internal block or intermediate plate of Figure 3a.

With reference to Figures 3a-b, an internal block or intermediate is illustrated, which is fitted to the housing 12 of the back part and secured to the wall via the insertion of adjusting bolts 28 through the corresponding holes 14.

The internal block 30 is provided with a cable positioning plate 32 in which recessed wire grooves 34 are formed. The ring main cable 10 is held in position by a cable clamping bar 36, and the wires 18, 20, 22 are held in the appropriate grooves 34 by a retaining bar 36.

Each wire is connected to an electrical terminal 40 as illustrated in Figure 3b. The electrical connector wire is secured in place by a screw, which is accessible 48 by an electrical probe to allow testing. The wire is connected 44 to a switch 46 such that when the switch is open, the wire is electrically isolated from the ring main 10.

The switch is connected via internal connecting strips 50 to electrical contacts 52 which correspond to the apertures 4 for receiving the plug of an electrical appliance.

The internal block is also provided with a transparent contact securing plate 54 which allows the user to visually inspect the condition of the switches and corresponding connectors. In addition, because terminals pivot upwards to open the switch, the securing plate 54 provides a safety feature in that it cannot be fitted if any of the switches are accidentally left open after the testing procedure, as the switch physically blocks the same.

After testing the front part 2 can be reconnected to the internal block 30 and back-box 12 of the back part by pushing in the quick-release fittings 8. The front part is guided into position by locating points 56.

With reference to Figures 4a-b, it will be appreciated that the arrangement of the switching means in the electrical socket, comprising incoming electrical connector 18, retaining bar 38, probe access screw 48, connector tester 44 and switch 46 can also be utilised in a consumer unit (corresponding components indicated with apostrophes) in connection with an appropriate fuse 58.

With reference to Figures 5a, an electrical socket is illustrated being fitted to a wall 60 in which a suitable recess 62 is formed, and to which the electrical connector wires 18, 20, 22 of a ring main 10 run.

Figures Sb-c show how the back-box is secured to the wall via screws 64 such that the wires extend into the back box.

As illustrated in Figure Sd, the internal block can then be S secured to the back box 12 via bolts 28, and the wires are connected to the terminals 40 and held in position by retaining bar 38.

The terminals 40 are covered by clear securing plate 54 to allow the same to be visually inspected.

As shown in Figure Se, a front plate 2 can then be connected to the back part by pushing quick release connectors 66 into the corresponding holes.

Thus to test the electrical system, an engineer simply removes the front part to reveal the internal block in the wall, actuates the terminal switches to isolate the socket, and performs the tests via the access points. When the test is complete the engineer closes the switches and replaces the front part.

Advantageously, this procedure all takes place without having to physically disconnect any electrical connectors from the ring main or pull out any wires.

As such the test procedure avoids damaging any connections, misaligning sockets, or chafing wires, and the time spent is only about a quarter of that required using conventional methods.

The cost savings and improvements in safety are therefore significant.

It will be appreciated by persons skilled in the art that the present invention may also include further additional modifications made to the device which does not affect the overall functioning of the device.

The internal block could be integral with, attached or detachably attached to the back part of the socket as required.

Referring to figure 7a, there is illustrated a prior art consumer unit or fuse board 200 for use in a building with an electrical supply. The fuse board is provided in an enclosure 202. It typically includes a residual current device (RCD) 204, which in this example is a 100 Amp RCD, which protects against faults in the earth connection occurring in electrical equipment in the building and reduces the risk of a user getting an electrical shock. A 32Amp RCD 206 is also provided. The live and neutral wires 208, 210 of a mains electrical supply are connected to the RCD 204, 206 and live and neutral wiring passes from the RCDs to the building ring main 212 including a plurality of electrical sockets 214, 216. An earth connection 218 is provided from the mains electrical supply in the enclosure. Wiring passes from the earth connection 218 through the ring main.

In accordance with an aspect of the present invention, the consumer unit or fuse board 300 forms part of an electrical system including an electrical socket as previously described, as shown in figure 7b. Isolation devices in the form of switches 302 are provided between the RCD and the ring main for each live, neutral and earth wire leaving the consumer unit. The isolation switches 302 work in a similar manner to isolation switches 46 provided in the electrical socket previously described. The switches are moved to an "open" or "switched off" position in order to electrically disconnect the electricity supply between two components to be tested (i.e. between an electrical socket and the fuse board). The switches need to be moved to a "closed" or "switched on" position in order to electrically connect the electricity supply between two components (i.e. between the electrical socket and the fuse board). In order to successfully test the ring main for electrical continuity, the switches of both the fuse board and a particular electrical socket being tested in the ring main need to be in an "open" position or "switched off".

Claims

Claims: 1. An electrical socket, said electrical socket including a front part and a back part, said front part including one or more apertures for the location of one or more pins of an electrical plug therethrough in use, said electrical socket further including electrical connection means for connecting an electrical supply and/or one or more electrical connectors to the pins of the electrical plug in use, and wherein the electrical connection means are provided on or associated with the back part, and the front part is selectively detachable from the back part in use without requiring disconnection of the back part and/or the electrical connection means provided on or associated with the back part.
2. An electrical socket according to claim I wherein the back part includes a housing for attachment to or in a support surface in use.
3. An electrical socket according to claim 1 wherein the electrical socket is a wall, ceiling or floor mountable electrical socket.
4. An electrical socket according to claim I wherein the electrical connection means include one or more mains electricity terminals.
5. An electrical socket according to claim 1 wherein the electrical connection means includes a live electrical connector, a neutral electrical connector and an earth electrical connector.
6. An electrical socket according to claim 1 wherein the electrical connection means includes one or more electrical contacts for receiving and/or contacting with the one or more pins of the electrical plug inserted through the apertures of the front plate in use.
7. An electrical socket according to claim 6 wherein the one or more apertures provided on the front part are located in a position or positions substantially aligned with or corresponding to the positions of the electrical contacts on or associated with the back part.
8. An electrical socket according to claim 7 wherein one or more groups or sets of three apertures are provided on the front part of the socket.
9. An electrical socket according to claim 5 wherein one or more sets of electrical connectors are provided on or associated with the back part; each set including an earth electrical connector, a live electrical connector and a neutral electrical connector, wherein one set of electrical connectors is provided for a single electrical socket, two sets of electrical connectors are provided for a double electrical socket and a third set of electrical connectors is provided for a spur.
10. An electrical socket according to claim I wherein isolation means are provided on or associated with the back part of the socket for electrically isolating two or more components from each other.
11. An electrical socket according to claim 10 wherein the isolation means electrically isolates the electrical connection means, the one or more electrical contacts and/or the electrical connectors.
12. An electrical socket according to claim 10 wherein the isolation means includes switching means or one or more electrical switches.
13. An electrical socket according to claim 12 wherein the one or more electrical switches are movable between a closed position, wherein electrical connection is made, and an open position, wherein electrical connection is disconnected.
14. An electrical socket according to claim 12 wherein the switches include one or more side by side or adjacentmountable terminals.
15. An electrical socket according to any preceding claim wherein the electrical connection means and/or each electrical connector is associated with a switch.
16. An electrical socket according to any preceding claim wherein each type of connector is associated with a switch.
17. An electrical socket according to any preceding claim wherein one switch is provided for all electrical connectors or a set or group of electrical connectors within a socket.
18. An electrical socket according to claim I wherein the back part is provided with testing means for allow a user to test an electrical circuit in use.
19. An electrical socket according to claim 18 wherein the testing means include one or more screws securing the electrical connectors in position on or with the back part.
20. An electrical socket according to any preceding claim wherein the isolation means and/or one or more switches prevent attachment of the front part to the back part when one or more switches are in the open position.
21. An electrical socket according to claim 20 wherein the isolation means and/or one or more switches extend outwardly of the back part when in the open position to physically prevent the front part and back part from coming together to form an electrical socket in use.
22. An electrical socket according to any preceding claim wherein a plate is provided to cover the isolation means and/or switches.
23. An electrical socket according to claim 22 wherein at least part of the plate is substantially transparent to allow visual inspection of the socket, switch and/or internal connections of the sockets by a user.
24. An electrical socket according to claims 22 or 23 wherein the plate forms part of the front part of the socket.
25. An electrical socket according to claim I wherein the front part is attachable to the back part via quick release means or one or more quick release connectors.
26. An electrical socket according to any preceding claim wherein the electrical connection means, the isolation means, one or mote switches, mains electricity terminals, electrical connectors and/or one or mote electrical contacts ate provided on an intermediate part that is attached or detachably attached to the back part.
27. An electrical socket according to any preceding claim wherein a consumer unit is connected to the electrical socket and the consumer unit includes isolation means.
28. A method of testing an electrical socket, said electrical socket including a front part and a back part, said front part including one or more apertures for the location of one or more pins of an electrical plug therethrough in use, said electrical socket further including electrical connection means for connecting an electricity supply and/or one or more electrical connectors to the pins of the electrical plug in use, said method including the steps of: -removing the front part of the electrical socket to reveal the back part with electrical connection means provided on or associated with the back part, the front part being detached without disconnecting the back part and/or the electrical connection means provided on or associated with the back part; and -testing the electrical socket.
29. A method according to claim 28 wherein the electrical connection means include one or more electrical contacts for receiving and/or contacting the pins of the plug in use and said testing step involves electrically isolating the electrical connectors from the electrical contacts.