Cover for electrical distribution equipment

Abstract

A cover 10 for electrical distribution equipment 11 such as an electricity meter, the electrical distribution equipment comprising: a body, one or more screw terminals for securing and making electrical connection with wires 24a-d, a screw guard 28a-d associated with each screw terminal, the screw guard being disposed in or on the body for receiving the screw 26a-f of the screw terminal and restricting access to the electrical connections, the cover comprising: a body for slidably attaching to the electrical distribution equipment, one or more protrusions 30a-d disposed on the body, each protrusion being disposed on an inner surface 40 of the body, for slotting into a corresponding one of the screw guards of the electrical distribution equipment, in use, each protrusion abutting a head of the screw of the associated screw terminal, and in use, the cover fitting flush with the electrical distribution equipment when all the electrical connections are securely fastened on the electrical distribution equipment.

Description

The present invention relates to a cover for electrical distribution equipment, which can be used to verify the integrity of electrical connections. BACKGROUND TO THE INVENTION A screw terminal is a type of electrical connection in which a wire is held by the tightening of a screw. Screw terminals are often used to connect wiring in buildings, for example, for connecting high-current appliances such as cookers. Electricity meters are commonly used to measure energy usage so that customers can be billed correctly, for example in a property. Meters handle high-current loads and often use screw terminals to secure wires. Meters are changed periodically, for example when the meter breaks and needs to be replaced, or when it reaches the end of its certified life. Currently many meters are being changed to replace them with “smart” meters. In these instances, new meters require correct installation of wires into the screw terminals. However, it has been found that this is not always being done correctly. Screw terminals only work when screws are properly tightened as only then can adequate conduction be maintained. Loose connections, for example from inadequate tightening of the screws, can be a problem. For example, electrical connection may not be maintained so the meter may not function correctly. Loose connections can also cause significant safety risks. If a wire comes loose, then live parts may be exposed where they can be touched. If the wire remains enclosed and connected but without making a good, low-resistance, connection, then there is a significant risk of overheating and subsequent fire. It is an object of the present invention to reduce or substantially obviate the aforementioned problems. STATEMENT OF INVENTION According to the present invention there is provided a cover for electrical distribution equipment, the electrical distribution equipment comprising: a body, one or more screw terminals for securing and making electrical connection with wires, a screw guard associated with each screw terminal, the screw guard being disposed in or on the body for receiving the screw of the screw terminal and restricting access to the electrical connections, the cover comprising: a body for slidably attaching to the electrical distribution equipment, one or more protrusions disposed on the body, each protrusion being disposed on an inner surface of the body, for slotting into a corresponding one of the screw guards of the electrical distribution equipment, in use, each protrusion abutting a head of the screw of the associated screw terminal, and in use, the cover fitting flush with the electrical distribution equipment when all the electrical connections are securely fastened on the electrical distribution equipment. This allows an installer to quickly and simply check if they have sufficiently secured electrical connections. If the screws have not been sufficiently tightened, then the protrusions will foul against the screw heads before the cover is sufficiently slid onto the equipment, so the cover will not fit flush with the electrical distribution equipment. Hence the problem will be obvious, instead of hidden. When fitted, the cover prevents access to the connections so that the equipment cannot be disconnected without removing the cover. The cover may be lockable or sealable to prevent unauthorised removal. The screw guard may provide a surround around the screw of the screw terminal. For example, the screw guard may be in the form of an indentation or aperture in the body of the equipment, which is just wide enough to receive the screw, and allow access for a screwdriver. In other embodiments, the screw guard may be a protrusion from the aperture, for example in the form of an open-ended cylindrical shell, which surrounds the screw. The guard may be sufficiently narrow and sufficiently deep that it prevents accidental touching of the screw head. This is to minimise the risk of electrocution. According to another aspect of the present invention there may be provided a cover for electrical distribution equipment, comprising: a body, one or more protrusions disposed on the body, the one or more protrusions disposed on an inner surface of the body, for slotting into screw guards of the electrical distribution equipment, in use, the one or more protrusions on the cover abutting a surface of one or more corresponding screw terminals on the electrical distribution equipment, and in use, the cover fitting flush with the electrical distribution equipment, when all the screw terminals are securely fastened. Fitting flush may be defined as a continuous front surface being formed when the cover is correctly fitted to the electrical distribution equipment. Fitting flush may also be defined as an outer surface of the cover being flush to an outer surface of the electrical distribution equipment. Fitting flush may also be defined as a front surface of the cover being flush to a front surface of the electrical distribution equipment. Since the cover fits flush only when relevant electrical connections have been adequately secured, this provides an easy way for the user to tell if the electrical connections are secure. One surface of cover may be flush with a surface of the electrical distribution equipment only when all the electrical connections are adequately tightened. One surface of the cover may be not flush with a surface of the electrical distribution equipment when at least one electrical connection is not adequately tightened. This allows the user to determine that there is a fault, even if only one of multiple electrical fastenings is not adequately secured. Protrusions may be substantially perpendicular to an inner surface of the body of the cover. This enables them to insert into corresponding screw guards of the electrical distribution equipment. Protrusions may be disposed on an inner surface of the cover. Protrusions may be disposed on an inner surface of the front of the cover. Protrusions may be substantially cylindrical. This allows each protrusion to insert into a corresponding cylindrical screw guard on the electrical distribution equipment. Protrusions may alternatively be substantially planar. This allows each protrusion to insert between opposing side walls of a screw guard on the electrical distribution equipment. Ridges may be provided on the cover. Grooves may be provided on the electrical distribution equipment. The grooves may correspond to the ridges provided on the cover. These guide the cover onto the electrical distribution equipment and thereby align the protrusions which can then insert into the screw guards with ease. In use, the cover slides with respect to the distribution equipment on the ridges and corresponding grooves. Each electrical connection may comprise one or more screws. Each electrical connection may be for retaining and making connection to one or more wires. The electrical connections may be between screws and wires. This allows the wires to be secured to the electrical distribution equipment. The screws may be suitable for use in screw terminals. The abutment of one or more protrusions with its respective electrical connection prevents the cover being completely slid on to the electrical distribution equipment if the screws are not sufficiently tightened. This allows the cover position to act as a proxy for how secure the electrical connections on the electrical distribution equipment are. The cover may partially cover each of a front, sides and a base of the electrical distribution equipment. The cover may be secured to the electrical distribution equipment by suitable fastening means. This prevents the need to replace the cover for verifying electrical connections on the distribution equipment, with a standard cover. In other words, the cover may form a permanent part of the electrical distribution equipment once installed. The fastening means may be for example one or more screws. The cover may have one or more corresponding threaded apertures to receive the one or more screws. The electrical distribution equipment may have one or more threaded apertures to receive the one or more screws. The screws may be suitable for use with tamper-evident seals to minimise the risk of unauthorised tampering. Alternatively, any suitable fastening means may be used to secure the cover to the electrical distribution equipment. The cover may be detachable from the electrical distribution equipment, for example by breaking the seal and undoing the screws. According to the present invention there is also provided a method for verifying if electrical connections are secured on electrical distribution equipment, comprising the steps of: providing the cover as claimed in preceding claims, sliding the cover onto the electrical distribution equipment and slotting the one or more protrusions into a one or more screw guards of the electrical distribution equipment, and checking if the cover fits flush with the electrical distribution equipment. Fitting flush may refer to a continuous front surface being formed. The method may further comprise a final step of securing the cover to the electrical distribution equipment. This may be done using one or more screws. The step of sliding the cover onto the electrical distribution equipment may further comprise the step of engaging ridges of the cover with corresponding grooves of the electrical distribution equipment. Alternatively, the step of sliding the cover onto the electrical distribution equipment may further comprise the step of engaging ridges of the electrical distribution equipment with corresponding grooves of the cover, to align the cover as it is slid onto the distribution equipment. The electrical distribution equipment may be an electricity meter. Electrical distribution equipment may further be any one of a meter, a switchboard, a junction box a time switch, a cut-out, other distribution equipment, or a connection for an appliance such as an oven. The cover may be suitable for use with any high-current electrical distribution equipment. High current may be defined as from for example 20 amperes to 400 amperes, or more particularly over 60 amperes, over 80 amperes, over 100 amperes, or over 150 amperes. Checking the screws of a screw terminal may be a proxy for verifying the integrity of electrical connections. The cover may be manufactured using 3D printing, casting, injection moulding or other suitable methods. The cover may be made from insulative material, for example plastics. However, in some embodiments the cover may be made from metal. This has the advantage that it is non-combustible although provision must be made for ensuring adequate insulation between the cover and the live electrical parts inside. The cover may be for verifying any number of electrical connections. According to another aspect of the present invention there is provided electrical distribution equipment, for example an electricity meter, having a cover of the type described. BRIEF DESCRIPTION OF THE DRAWINGS For a better understanding of the present invention, and to show more clearly how it may be carried into effect, reference will now be made by way of example only to the accompanying drawings, in which: Figure 1 shows an embodiment of a cover disposed on a meter when electrical connections are secured; Figure 2 shows the meter of Figure 1 without the cover; Figure 3 shows the cover of Figure 1; Figure 4 shows the cover disposed on the meter of Figure 1 when one or more electrical connections are not secured; Figure 5 shows an alternative embodiment of a cover, disposed on an alternative embodiment of a meter when electrical connections are secured; Figure 6 shows the meter of Figure 5 without the cover; Figure 7 shows the cover of Figure 5; and Figure 8 shows the cover disposed on the meter of Figure 5, when one or more electrical connections are not secured. DESCRIPTION OF PREFERRED EMBODIMENTS Figures 1 to 4 show one embodiment of the invention, and Figures 5 to 8 show an alternative embodiment of the invention. Referring firstly to Figure 1 a cover, indicated generally at 10, is shown disposed on an electricity meter, indicated generally at 11. Figure 1 shows a view in which the electrical connections are adequately secured, and the cover fits flush. The cover 10 has a front 12, a first side 14, a second side (not visible in Figure 1), and a base 16. The meter 11 comprises a front 22, a first side 23, a second side (not visible) and a base 27. The front 12 of the cover 10 further comprises a sloped portion 18. The sloped portion 18 is sloped towards the base portion 16. The sloped portion 18 is at an angle relative to the base portion 16. The sloped portion 18 is at an angle relative to the front portion 12. The base portion 16 of the cover 10 is shaped to allow electrical wiring 24 to extend unimpeded out of the base 27 of the meter 11. In this embodiment, the base portion extends around a front and sides of the base 27 of the meter 11. In this arrangement, screws (see Figure 2) of the electrical meter 11 are sufficiently tightened and the cover fits flush, that is to say a continuous front surface is formed. The front 12 of the cover 10 is continuous with the front 22 of the meter 11. Sides 23 of the meter 11 are flush with the sides 14 of the cover 10. The base 16 of the cover 10 is flush with the base 27 of the meter 11. The cover 10 comprises an upper edge 20 at the top of the front portion 12. The upper edge 20 is straight in this embodiment. Alternatively, it may be shaped to match the corresponding edge of the meter 111. The edge 20 abuts the front 22 of the meter 11. Figure 2 shows the meter 11 without the cover 10. Electrical wires 24 are secured to the meter 11. The meter 11 comprises screw terminals for securing each electrical wire 24. Four screw guards 28 are disposed on the meter 11 for guiding screws into position and preventing installers from accidentally touching screws. Screws 26 are disposed on the meter 11 for securing the wiring 24. Each screw is surrounded by a corresponding screw guard 28 and holds a corresponding wire, for example screw guard 28a surrounds screws 26e, 26f which hold wire 24a. Side alignment grooves 38 are provided on sides 23, 25 of the meter 11. Front alignment groove 39 is provided at a front 22 of the meter 11. Side and front grooves are parallel to the base 27 of the meter 11. The front groove 39 and side grooves 38 are disposed in the same plane. The front groove 39 and side grooves 38 are continuous in this embodiment. These receive a cover 10 (not shown) for the meter 11. Figure 3 shows the cover 10 when removed from the meter 11. Protrusions 30 are disposed on an inner surface 40 of the base 16 and an inner surface of the sloped portion 18, of the cover 10. The protrusions 30 are substantially perpendicular to the inner surface 40 of the base 16 and the inner surface 40 of the sloped portion 18 of the cover 10. The protrusions 30 are substantially planar in this embodiment. Four protrusions 30 are disposed on the cover 10. The protrusions 30 are spaced along the base 16 of the meter 11. The protrusions 30 each comprise a back-facing flat edge 42 for abutting the screws 26 of the meter 11. The protrusions 20 abut a surface of the screw head. Each protrusion 30 corresponds to a screw guard 28 of the meter 11, for example protrusion 30a of cover 10 corresponds to screw guard 28a of meter 11. In use, each protrusion 30 inserts into its corresponding screw guard 28. The protrusions 30 are of a width such that each protrusion 30 can insert into its respective screw guard 28. A front ridge 44 is provided along an upper edge of the front 22 of the cover 10. Side ridges 46 are provided along upper edges of sides 14, 15. Each ridge 44, 46 is disposed perpendicular to an inner surface of the cover. Each ridge 44, 46 is disposed on an inside surface of the cover, protruding inwards. The side ridges 46 and front ridges 44 adjoin, i.e., are continuous in this embodiment. In use, side ridges 46 of the cover 10 are inserted into side grooves 38 of the meter. The cover of the meter is slid onto the meter, aligned by these ridges. Front ridge 44 has an edge 45. Edge 45 of the cover abuts groove 39 of the meter only if screws 26 are adequately tightened. Figure 4 shows the cover 10 on meter 11 when one or more of the screws 26 are not adequately tightened. Therefore, the cover does not fit completely flush. An edge 20 of the cover 10 is therefore not aligned with the front of the meter 22. In this instance, the front 12 of the meter is not flush with the front of the meter. A portion of the first side 14, second side 15, and base 16 of the cover are flush with the front, sides and base of the meter. No continuous front surface is formed. This provides a visual indicator that one or more screws 26 are not sufficiently tightened so the user can adjust them accordingly. In use, side ridges 46 of the cover 10 are slid into side grooves 38 of the meter 11 and in this manner, the cover 10 is slid onto the meter 11. In this instance, the protrusions 30 abut a surface of one or more inadequately tightened screws 26 and the cover 10 is prevented from being slid onto the meter 11 completely. Figures 5 to 8 show an alternative embodiment of the meter 111, and a corresponding alternative embodiment of the cover 110. Figure 5 shows cover 110 on meter 111 when the screws (not shown) are adequately tightened. The cover 110 has a front 112, first side (not shown), a second side 115, a base 116 and a sloped portion 118, as in previous embodiments. The meter 111 comprises a front 122, first side (not shown), second side 125 and base 127, as in previous embodiments. Apertures 148 are disposed on the sloped portion 118 of the cover 110. This is to enable the cover 110 to be slid onto the meter 111 without being hindered when screws are sufficiently tightened. The front 112 of the cover 110 has an additional extension at its top for fitting flush with the shape of the front 122 of the meter 110. Figure 6 shows the meter 111 without the cover. The meter 111 comprises screw terminals for holding electrical wires 124, as in previous embodiments. Screw guards 128 are disposed on the meter 111 for guiding screws into position and to prevent the user accidentally touching the electrical connections. Each electrical connection is secured by a pair of screws 126. Each pair of screws, for example 126e, 126f hold an electrical wire 124a. Each screw 126 is surrounded by an alternative embodiment of a screw guard 128. In this embodiment, each screw guard 128 is provided as an aperture. Each screw guard 126 has been provided as an aperture in the front 122 of the meter 111. As in previous embodiments, alignment grooves are provided on the meter, indicated as side grooves 138 and front groove 139. Figure 7 shows the inside of cover 110. Pairs of prongs 132, 134 are disposed on the internal surface of the front of the cover 112. Each pair comprises an upper prong 134 and a lower prong 132. Each pair of prongs is spaced along an inner surface of cover 110. Each prong 132, 134 corresponds to a screw guard 128 on the cover 110. That is to say, each pair of prongs, for example 134a and 132a insert into a corresponding pair of screw guards 126e, 126f. In this embodiment, upper prongs 134 are disposed on an inner surface of the front 112 of the cover 110. Lower prongs 132 are disposed on an inner surface of the sloped portion of the cover 118. Each prong 132, 134 is substantially cylindrical in shape. Each prong 132, 134 is substantially perpendicular to the front of the cover 112. Each prong 132, 134 is substantially parallel to first and second sides 114, 115 of the cover 110. Each prong 132, 134 is disposed such that it corresponds to a screw guard 128. Ridges 144, 146 are provided on the cover 110, as in previous embodiments. In use, side ridges 146 of the cover 110 are inserted into side grooves 138 of the meter, as in previous embodiments. The front ridge 144 matches the form of an upper edge of the cover 110. The cover 110 is slid onto the meter 111, guided by ridges 146. Figure 8 shows cover 110 disposed on meter 111. In this arrangement one or more screws 126 are not sufficiently tightened. Therefore, the cover 110 is prevented from fully sliding onto the meter 111. Front 112 of the cover 110 is not flush with the front 122 of the meter 111. A portion of side 115 of the cover 110 is flush with a portion of side 123 of the meter 111. A portion of the base of the cover 110 is flush with a portion of the base of the meter 111. In use, the process is as follows, for either embodiment. Attempts are made to tighten screws 26 that hold electrical wires 24 to secure the electrical connections. Side alignment ridges 46 of a cover 10 are slid onto corresponding grooves 38 of electrical distribution equipment 11. The cover 10 is slid onto the electrical distribution equipment 11. If a front 12 of the cover 10 is not flush with a front 22 of the meter 11 when the cover is slid onto the meter 11, the cover 10 is removed, and one or more attempts are made to tighten the screws 26. The cover 10 is placed back onto the meter 10 again to check if the screws 26 have been adequately tightened. This process is repeated until the cover 10 is flush with the meter 11, i.e., a continuous front surface is formed. If the surface of the front 12 of the cover 10 is flush with the front surface 22 of the meter 11, then the electrical connections are assumed to be secure. In some embodiments, the cover 10 is then removed, and a standard meter cover is slid onto the meter and screwed on to the meter 11 over the screw terminals. In other embodiments, the cover as described and pictured is left on the meter 10 and screwed directly onto the meter 10. In that case, one or more threaded holes are preferably provided on a meter. Corresponding one or more apertures are provided on the cover. The screw can then be inserted through an aperture on the cover and tightened by screwing the screw into the threaded hole of the meter. The screw is suitable for attachment of a tamper-evident seal. In other embodiments, alternative fastening arrangements may be provided. A screw terminal is defined as a type of electrical connection in which a wire is held by the tightening of a screw. Flush is defined as directly abutting or immediately adjacent. The cover 10 fitting flush is defined as a continuous front surface being formed. That is to say, a front surface 12 of the cover 10 forms a substantially continuous surface with the front surface 22 of the meter 11. In these embodiments, electrical connections being securely fastened mean that the screws are sufficiently tightened. The embodiments described above are provided by way of example only, and various changes and modifications will be apparent to persons skilled in the art without departing from the scope of the present invention as defined by the appended claims.

Claims

1. A cover for electrical distribution equipment,the electrical distribution equipment comprising:a body,one or more screw terminals for securing and making electrical connection with wires,a screw guard associated with each screw terminal, the screw guard being disposed in or on the body for receiving the screw of the screw terminal and restricting access to the electrical connections,the cover comprising:a body for slidably attaching to the electrical distribution equipment,one or more protrusions disposed on the body,each protrusion being disposed on an inner surface of the body, for slotting into a corresponding one of the screw guards of the electrical distribution equipment,in use, each protrusion abutting a head of the screw of the associated screw terminal, andin use, the cover fitting flush with the electrical distribution equipment when all the electrical connections are securely fastened on the electrical distribution equipment.

2. The cover of claim 1, in which an outer surface of the cover is flush to an outer surface of the meter when the cover fits flush.

3. The cover of claim 1 or 2, in which a front surface of the cover is flush to a front surface of the meter, thereby forming a substantially continuous front surface when the cover fits flush.

4. The cover of any one of claims 1 to 3, in which the cover fits flush only when all the electrical connections are adequately secured.

5. The cover of any one of claims 1 to 4, in which the cover does not fit flush with a surface of the meter when at least one electrical connection is not adequately secured.

6. The cover of any one of claims 1 to 5, in which each protrusion is substantially perpendicular to the inner surface of the body of the cover.

7. The cover of any one of claims 1 to 6, in which each protrusion is are disposed on an inner surface of the front surface of the cover.

8. The cover of any one of claims 1 to 7, in which the one or more protrusions are substantially cylindrical.

9. The cover of any one of claims 1 to 7, in which the one or more protrusions are substantially planar.

10. The cover of any one of claims 1 to 9 in which ridges or grooves are provided on the cover for guiding the cover onto the meter.

11. The cover of any one of claims 1 to 10, in which each electrical connection comprises one or more screws.

12. The cover of any one of claims 1 to 11, in which each electrical connection be for retaining and making connection to one or more wires.

13. The cover of any one of claims 1 to 12, in which the cover partially covers a front, sides and base of the electrical distribution equipment.

14. The cover of any one of claims 1 to 13, in which the cover can further be secured to the electrical distribution equipment by suitable fastening means.

15. The cover of any one of claims 1 to 14, in which the electrical distribution equipment is an electricity meter.

16. The cover of any one of claims 1 to 15, in which the electrical distribution equipment is any one of a meter, a switchboard, a junction box, a time switch, a cut-out, other distribution equipment or a connection for an appliance.

17. The electrical distribution equipment of claim 1, when dependent on claim 10, in which grooves are provided on the electrical distribution equipment for guiding the cover onto the meter.

18. A method for verifying if electrical connections are secured on electrical distribution equipment, comprising the steps of:providing the cover as claimed in preceding claims,sliding the cover onto the electrical distribution equipment and slotting the one 5 or more protrusions into corresponding one or more screw guards of theelectrical distribution equipment, andchecking if the cover fits flush with the electrical distribution equipment.

19. The method of claim 18, which further comprises a final step of securing the cover to the electrical distribution equipment.10 20. The method of claim 18, when dependent on claims 10 and 17, in which slidingthe cover onto the electrical distribution equipment further comprises engaging ridges of the cover with corresponding grooves of the electrical distribution equipment.The method of claim 18, when dependent on claims 10 and 17, in which sliding 15 the cover onto the electrical distribution equipment further comprises engagingridges of the electrical distribution equipment with corresponding grooves of the cover.

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