RECEPTACLE ASSEMBLY WITH GASKET

Abstract

Example embodiments relate to receptacle assemblies with gaskets. One example includes a receptacle assembly for a luminaire system. The receptacle assembly includes a receptacle and a gasket. The receptacle has a front side and a rear side. The front side is configured for receiving electrical contacts of an external module. The rear side is configured for extending in an opening of a housing, preferably a luminaire housing, and for being electrically connected to components in the housing. The gasket is configured for being located between the receptacle and the housing on which the receptacle is to be mounted. The receptacle assembly is provided with an indicator means at a location which is visible when the receptacle is mounted on the housing.

Claims

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39. A receptacle assembly for a luminaire system, said receptacle assembly comprising a receptacle and a gasket; said receptacle having a front side and a rear side, said front side being configured for receiving electrical contacts of an external module, said rear side being configured for extending in an opening of a housing, preferably a luminaire housing, and for being electrically connected to components in the housing; said gasket being configured for being located between the receptacle and the housing on which the receptacle is to be mounted; wherein said receptacle assembly is provided with an indicator means at a location which is visible when the receptacle is mounted on the housing.

40. The receptacle assembly of claim 39, wherein the receptacle is configured to receive and cooperate with the external module, and the indicator means is provided to the receptacle assembly at a location which is visible when the external module is mounted on the receptacle.

41. The receptacle assembly of claim 39, wherein the indicator means is provided to the gasket at a location which is visible when the receptacle is mounted on the housing.

42. The receptacle assembly of claim 41, wherein the indicator means is an integral part of the gasket.

43. The receptacle assembly of claim 39, wherein the indicator means is configured to indicate a correct positioning of the external module in the receptacle.

44. The receptacle assembly of claim 39, wherein the receptacle is configured to receive the external module by inserting and twisting, and wherein the indicator means is configured to indicate when the external module is in the correct twisted position.

45. The receptacle assembly of claim 39, wherein the indicator means comprises a lip protruding outwardly from a periphery of the gasket, preferably over a length which is more than 10 mm, more preferably more than 15 mm.

46. The receptacle assembly of claim 39, wherein the receptacle has a housing comprising a substantially cylindrical front portion at the front side of the receptacle, and a rear portion protruding rearwardly at a rear side of the substantially cylindrical front portion and intended to extend through an opening in the housing, and wherein the gasket is configured to be arranged around said rear portion; and/or wherein the receptacle is provided with a flat portion on the peripheral wall between the front side and the rear side to ensure a proper alignment of the receptacle with respect to the opening in the housing, wherein the gasket is provided with an opening through which the rear side of the receptacle extends, and wherein a peripheral inner wall of the gasket delimiting said opening is provided with a corresponding flat wall section; and/or wherein the receptacle is provided at the rear side thereof with a screw-thread, and wherein the receptacle assembly further comprises a nut configured to be screwed on the screw-thread of the receptacle.

47. The receptacle assembly of claim 39, wherein the receptacle is provided with at least two fixation through-holes for receiving at least two fixation means for fixing the receptacle on the housing, and wherein the gasket is provided with at least two corresponding through-holes through which said at least two fixation means can extend; wherein preferably the at least two fixation though-holes comprise a first and a second fixation through-hole located at opposite sides of the receptacle, and wherein the at least two corresponding though-holes in the gasket comprise a first and a second through-hole located at opposite sides of the gasket; wherein preferably a radial line through the first and second through-hole of the gasket and a radial line through the indicator means are at an angle between 85° and 105°, preferably between 90° and 100°.

48. The receptacle assembly of claim 39, wherein the gasket has a ring shaped portion and a lip portion connected to an outer periphery of the ring shaped portion; and/or wherein the outer periphery of the ring-shaped portion is substantially circular with an outer diameter between 40 mm and 100 mm, preferably between 55 mm and 80 mm, and wherein a radial length of the lip portion is larger than 10 mm.

49. The receptacle assembly of claim 39, wherein the gasket has a top surface intended to be in contact with the receptacle and a bottom surface intended to be in contact with the housing; wherein preferably the top surface is provided with a least one alignment feature configured to align the gasket with respect to the receptacle; and/or wherein preferably the top surface is provided with a peripheral rib configured to be in sealing engagement with the receptacle; and/or wherein preferably the bottom surface is provided with at least one peripheral rib configured to be in sealing engagement with the housing.

50. The receptacle assembly of claim 49, wherein the at least one alignment feature comprises at least two protrusions; wherein preferably the at least two protrusions are arranged on the peripheral rib.

51. The receptacle assembly of claim 39, wherein the receptacle houses a plurality of receptacle contacts; wherein preferably each receptacle contact is provided, at a front end, with a front contact portion configured for being electrically connected with a contact of the external module, and, at a rear end, with at least one wire receiving contact portion in which at least one wire is fixed; and/or wherein preferably the plurality of receptacle contacts comprises a plurality of first receptacle contacts and optionally one or more second receptacle contacts.

52. The receptacle assembly according to claim 51, wherein seen in a radial direction around a central axis of the receptacle, the plurality of first receptacle contacts is positioned further away from the central axis than the one or more second receptacle contacts; and/or wherein the plurality of first receptacle contacts extends substantially along a first cylindrical surface around a central axis of the receptacle.

53. The receptacle assembly according to claim 51, wherein the at least one second receptacle contact comprises a plurality of second receptacle contacts extending substantially along a second cylindrical surface around a central axis of the receptacle; and/or wherein front contact portions of the plurality of first receptacle contacts extend flush with the front side of the receptacle; and/or wherein the plurality of receptacle contacts comprises at least three receptacle contacts comprising: at least one receptacle contact for carrying a power signal, and/or at least one receptacle contact for carrying data or control signals, and/or at least one receptacle contact for carrying power signals and data or control signals.

54. The receptacle assembly according to claim 39, wherein the receptacle comprises an RFID tag, preferably at the front side of the receptacle; and/or wherein the receptacle is configured for being substantially surrounded by the external module when the external module is mounted on the receptacle; and/or wherein a diameter of the receptacle is smaller than a diameter of the external module, and a diameter of the gasket is larger than the diameter of the external module at least at the location of the indicator means; and/or wherein the gasket is provided with an outwardly protruding portion configured for, at the location of the indicator means, extending beyond the external module when the external module is mounted on the receptacle.

55. Use of a receptacle assembly according to claim 39, for mounting an external module, said external module having an indication, wherein said indication is aligned with the indicator means of the receptacle assembly, preferably of the gasket of the receptacle assembly.

56. Use of a receptacle assembly according to claim 39, for transferring at least two power signals and at least one data and/or control signal via a plurality of receptacle contacts between one or more components of an external module and one or more components arranged in a housing of a luminaire system.

57. A gasket for use in a receptacle assembly of a luminaire system, said gasket being configured for being located between a receptacle and a housing on which the receptacle is to be mounted; wherein said gasket is provided with an indicator means at a location which is visible when the receptacle is mounted on the housing.

58. A luminaire comprising electrical components, a luminaire housing in which the electrical components are arranged, and a receptacle assembly, said receptacle assembly comprising a receptacle and a gasket; said receptacle having a front side and a rear side, said front side being configured for receiving electrical contacts of an external module, said rear side being configured for extending in an opening of a housing, preferably a luminaire housing, and for being electrically connected to components in the housing; said gasket being configured for being located between the receptacle and the housing on which the receptacle is to be mounted; wherein said receptacle assembly is provided with an indicator means at a location which is visible when the receptacle is mounted on the housing; said luminaire housing having an opening, wherein the receptacle is arranged partially in the opening of the luminaire housing with its rear side facing an inner space of the luminaire housing and its front side accessible outside the luminaire housing, wherein the gasket is arranged between the receptacle and an outer surface of the housing, around the opening with the indicator means visible, and wherein wires connect the receptacle to the electrical components; preferably further comprising a light source arranged in the luminaire housing.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0067] The accompanying drawings are used to illustrate presently preferred non-limiting exemplary embodiments of devices of the present invention. The above and other advantages of the features and objects of the invention will become more apparent and the invention will be better understood from the following detailed description when read in conjunction with the accompanying drawings, in which:

[0068] FIG. 1 is a schematic exploded view of an exemplary embodiment of a receptacle assembly;

[0069] FIG. 1A is a schematic perspective view of the receptacle of FIG. 1 seen from the other side;

[0070] FIG. 2A is a bottom view of the gasket of FIG. 1;

[0071] FIG. 2B is a side view of the gasket of FIG. 1;

[0072] FIG. 2C is a top view of the gasket of FIG. 1;

[0073] FIG. 2D is a perspective view of the gasket of FIG. 1;

[0074] FIG. 3 is a schematic top view of an exemplary embodiment of a receptacle assembly in the mounted state, wherein also the periphery of an external module has been indicated;

[0075] FIGS. 4A and 4B are top views of other exemplary embodiments of a gasket;

[0076] FIG. 5 is a schematic perspective view of an embodiment of a receptacle assembly mounted in a luminaire housing H and of a external module to be plugged in the receptacle of the receptacle assembly;

[0077] FIG. 6 is a schematic perspective view of another exemplary embodiment of a receptacle;

[0078] FIG. 7 is a schematic view of a luminaire head comprising a receptacle;

[0079] FIG. 8A shows a receptacle assembly and a compatible external module to be mounted;

[0080] FIG. 8B shows the receptacle assembly of FIG. 8A with the external module partly mounted;

[0081] FIG. 8C shows the receptacle assembly of FIG. 8A with the external module completely mounted; and

[0082] FIGS. 9A and 9B show different embodiments of an alternative receptacle assembly and external module mounted thereon.

DESCRIPTION OF EMBODIMENTS

[0083] FIG. 1 illustrates an exemplary embodiment of a receptacle assembly for e.g. a luminaire system, typically for an outdoor or industrial luminaire. The receptacle assembly 1000 comprises a receptacle 100, a nut 300 for fixing the receptacle 100 in an opening of a luminaire housing H (not shown in FIG. 1), and a gasket 400 to be inserted between the receptacle 100 and the luminaire housing H.

[0084] By outdoor or industrial luminaires, it is meant luminaires which are installed on roads, tunnels, industrial plants, stadiums, airports, harbors, rail stations, campuses, parks, cycle paths, pedestrian paths or in pedestrian zones, for example, and which can be used notably for the lighting of an outdoor area or large indoor area, such as roads and residential areas in the public domain, private parking areas and access roads to private building infrastructures, warehouse, industry halls, etc.

[0085] Luminaire systems for roadways, parking lots and other outdoor or industrial areas typically use plug twist-lock external modules 500 (see FIG. 5) containing different control blocks and/or sensors (not shown). An external module 500 may comprise e.g. a light sensor for sensing the light level of ambient light to automatically switch light fixtures on at dusk and off at dawn. More generally the external module 500 may comprise any one of the following: a sensor (e.g. a light sensor, a motion sensor, a passive infrared sensor, an environmental sensor, a visibility sensor, an image sensor, a radar sensor, a sound sensor, a voice recorder, a pollutant sensor, a microphone, a detector of CO2, NOx, smoke etc.), communication circuitry, control circuitry, protection circuitry (e.g. an SPD or a fuse), metering circuitry, an actuator, an energy storage element, etc. For uniformity throughout the lighting industry, electrical receptacles 100 for receiving such external modules 500 are mostly made according to specific standards such as standards approved by American National Standards Institute, Inc. (ANSI). Such receptacles 100 are typically mounted on a luminaire housing H (see FIG. 5), e.g. on a top or bottom surface of the luminaire housing, and are electrically connected to various components (not shown) of the lighting equipment through wires. An external module 500 is plugged into a receptacle 100 to provide e.g. control of the luminaire system.

[0086] The external module 500 typically comprises three standard prongs 520 (see FIG. 5, also called plug contacts or simply contacts) which are inserted into corresponding apertures 160 in the receptacle 100. After the prongs 520 are completely inserted, the external module 500 is rotated to lock it in place. When locked in place, the prongs 520 contact the receptacle contacts 120a-c, see also FIG. 3 which will be discussed in detail below. The external module 500 may comprise further contacts 510 in the form of conductive springs for cooperating with receptacle contacts 110a-d of receptacle 100 in the form of conductive plates, see also FIG. 3 which will be discussed in detail below. Preferably, the receptacle 100 and the external module 500 fulfil the requirements of the ANSI C136.10-2017 standard or the ANSI C136.41-2013 standard.

[0087] The receptacle 100 has a front side 101 and a rear side 102. The front side 101 is configured for receiving contacts of the pluggable external module (not shown). An RFID tag may be provided at or near the front side 101, as indicated with arrow 199 in FIG. 1. The receptacle 100 is shown in FIGS. 1, 1A and 3. As shown in FIG. 3, the receptacle 100 houses a plurality of receptacle contacts 110a-d, 120a-c. Each receptacle contact 110a-d, 120a-c may be provided, at a front end, with a front contact portion configured for being electrically connected with a contact of an external module. Each receptacle contact 110a-d, 120a-c may be provided, at a rear end, with a wire receiving contact portion fixing a wire end of a wire 113 to be connected to components of the luminaire system. A receptacle contact 110a, 120a of said plurality of receptacle contacts may be provided, at said rear end, with one wire or with two or more wires. Preferably, the plurality of receptacle contacts 110a-d, 120a-c comprises at least two receptacle contacts for carrying power signals and/or one or more receptacle contacts for carrying data or control signals and/or one or more receptacle contacts for carrying both power signals and data or control signals. In the illustrates embodiment receptacle contacts 110a-d may be for carrying data or control signals and receptacle contacts 120a-c may be for carrying power signals.

[0088] The plurality of receptacle contacts 110a-d, 120a-c comprises a plurality of first receptacle contacts 110a-d and a plurality of second receptacle contacts 120a-c. As is best visible in FIG. 3, seen in a radial direction around a central axis A of the receptacle 100, the plurality of first receptacle contacts 110a-d are positioned further away from the central axis than the plurality of second receptacle contacts 120a-c. The plurality of first receptacle contacts 110a-d extends in an axial direction, substantially along a first (virtual) cylindrical surface around the central axis A, and the plurality of second receptacle contacts 120a-c extends in an axial direction, substantially along a second (virtual) cylindrical surface around the central axis A, said second cylindrical surface having a smaller diameter than said first cylindrical surface. The front contact portions 111a-d of the plurality of first receptacle contacts 110a-d extend flush with the front side 101 of the receptacle 100.

[0089] As shown in FIGS. 1 and 1A, the receptacle 100 may comprise a substantially cylindrical front portion 181 at the front side 101 of the receptacle 100, and a substantially cylindrical rear portion 182 at the rear side 102 of the receptacle 100. The front portion 181 has larger dimensions than the rear portion 182. The rear portion 182 is intended to be arranged through an opening in a housing of a luminaire, whilst the front portion 181 abuts against a wall of the luminaire housing. The substantially cylindrical rear portion 182 may be provided with a screw thread 170 for cooperating with a corresponding screw-thread 370 of the nut 300. As shown in FIG. 1, the nut 300 may be provided with a ribbed surface or a surface with a certain surface roughness, said surface being intended for being in contact with an inner surface of the luminaire housing. This will allow obtaining an improved fixation of the receptacle 100 in an opening of the luminaire housing H. In addition or alternatively, the receptacle 100 may also be fixed to the luminaire housing using screws which extend through fixation through-holes 195 provided in the front portion 181 of the receptacle 100, e.g. two diametrically opposite through-holes 195 as illustrated. Optionally, the receptacle 100 may be provided with a flat portion 190 on the peripheral wall of the rear portion 182 to ensure a proper alignment of the receptacle 100 with respect to the luminaire housing, and for some applications also a desired orientation with respect to the road. The receptacle 100 may be formed in one or in two or more parts. For example, the receptacle 100 may comprise a central body portion and a flange portion which are coupled to each other.

[0090] The gasket 400 is configured for being located between the receptacle 100 and the housing H on which the receptacle is to be mounted, and more in particular between the front portion 181 of the receptacle 100 and the housing. The gasket 400 is provided with an indicator means 410 at a location which is visible when the receptacle is mounted on the housing. This can be best understood when looking at the top view of FIG. 3 which shows that the indicator means 410 extends out of an area covered by the receptacle 100, and preferably even out of an area covered by the external module 500, seen in a top view of the mounted assembly. More in particular, FIG. 3 shows the contours of two external modules 500, one with a diameter De1 and one with a diameter De2. It can be seen that the indicator means 410 extends further than the contour of the external modules 500. In this way the indicator means 410 will be well visible to an operator mounting an external module 500. Preferably, the indicator means is configured to indicate a correct positioning of the external module 500 in the receptacle 100. More preferably, the receptacle 100 is configured to receive the external module 500 by inserting and twisting, as explained above in connection with FIG. 5, and the indicator means 410 is configured to indicate when the external module 500 is in the correct twisted position.

[0091] Preferably, the indicator means is an integral part of the gasket. Preferably, the indicator means is made of the same material as the gasket in a common mould. However, the indicator means could also be provided in a different manner, e.g. by overmoulding, and the indicator means could be made of a different material.

[0092] In the example of FIG. 1 and FIGS. 2A-2D, the indicator means 410 comprises a lip 411 protruding outwardly from an outer periphery 422 of the gasket 400, preferably over a length which is more than 10 mm, more preferably more than 15 mm. The gasket 400 is configured to be arranged around the rear portion 182 of the receptacle 100. The gasket 400 is provided with an opening 430 through which the rear side 102 of the receptacle 100 extends. In the illustrated embodiment, the gasket 400 has a peripheral inner wall 421a, 421b delimiting the opening 430, and the peripheral inner wall is provided with a cylindrical wall section 421b and a flat wall section 421a corresponding with the flat wall portion 190 of the rear portion 182. The gasket 400 is further provided with two through-holes 495 through which two fixation means such as screws can extend and which correspond with the fixation through-holes 495. Preferably, a radial line L1 through the first and second through-hole of the gasket and a radial line L2 through the indicator means are at an angle between 85° and 105°, preferably between 90° and 100°, see FIG. 3.

[0093] The gasket 400 is formed with a ring shaped portion 420 and the lip 411 connected to an outer periphery 433 of the ring shaped portion 420. The outer periphery 422 of the ring-shaped portion is substantially circular with an outer diameter D between 40 mm and 100 mm, preferably between 55 mm and 80 mm. Preferably, a radial length L of the lip 411 is larger than 10 mm, more preferably larger than 15 mm.

[0094] The gasket 400 has a top surface 440 intended to be in contact with the receptacle 100 and a bottom surface 450 intended to be in contact with the housing. The top surface 440 is provided with a least one alignment feature configured to align the gasket with respect to the receptacle, here three protrusions 442 arranged on a peripheral rib 441 configured to be in sealing engagement with the receptacle 100, see FIGS. 2B, 2C and 2D. The bottom surface 450 is provided with at least one peripheral rib 451, here three peripheral ribs 451, configured to be in sealing engagement with the housing, see FIG. 2A.

[0095] FIGS. 4A and 4B illustrate two further embodiments of suitable gaskets 400. In the embodiment of FIG. 4A, the indictor means 410 is formed by giving the gasket a polygonal outer periphery 422, such that one or more of the corners of the gasket 400 may form an indicator means 410. In the embodiment of FIG. 4B, the gasket 400 is provided with two lips 411 instead of one lip. This may further facilitate the visibility of the indicator means from different sides of the receptacle assembly. This skilled person understands that many variants are possible and that the gasket 400 may be given many suitable shapes that will result in an indicator means being present.

[0096] FIG. 6 illustrates another exemplary embodiment of a receptacle 100 having a front side 101 and a rear side 102, which may be used in embodiments of the invention. The receptacle 100 may be in accordance with the Zhaga standard (see LEX-R in book 18, Edition 1.0, July 2018). The front side 101 is configured for receiving electrical contacts of an external module (not shown) of a lighting equipment. The external module may also be in accordance with the Zhaga standard (see LEX-M in book 18, Edition 1.0, July 2018). The rear side 102 is intended for being electrically connected to components of the lighting equipment, such as a driver, a controller, a sensor, a metering device, an energy storage device, an actuator, protection circuitry, such as ESD, SPD, etc. (see also the list included above in the summary). The receptacle 100 houses a plurality of receptacle contacts 210a-d (shown in a schematic manner in FIG. 6) in apertures 160a-d arranged in the front side 101.

[0097] Each receptacle contact 210a-d is provided, at a front end, with a front contact portion configured for being electrically connected with a contact of the external module, e.g. a prong similar to the prong 520 of FIG. 5, and, at a rear end, with at least one wire receiving contact portion in which at least one wire 123 is fixed. The front contact portions of the plurality of receptacle contacts 210a-d extend near the front side 101 of the receptacle 100. The plurality of receptacle contacts 210a-d extends substantially along a first cylindrical surface around a central axis of the receptacle. The front side 101 of the receptacle 100 may be provided with a central recess 165 configured for receiving a central pin of the external module, preferably in accordance with the above mentioned Zhaga standard. Optionally, the receptacle 100 comprises an RFID tag (not shown in FIG. 6), preferably at the front side 101 of the receptacle 100. Also other components may be included in the receptacle 100, such as wireless communication means, sensor means, an antenna, protection circuitry, etc.

[0098] The receptacle 100 has a housing comprising a substantially cylindrical front portion 181 at the front side 101 of the receptacle 100, and a rear portion 182 protruding rearward at a rear side of the cylindrical front portion 181. The rear portion 182 is provided at the rear side thereof with a screw-thread 170. The receptacle assembly may further comprise a nut (not shown in FIG. 6) configured to be screwed on the screw-thread 170. The substantially cylindrical front portion 181 may comprise a first substantially cylindrical front portion 181a having a first diameter and a second substantially cylindrical front portion 181b having a second diameter which is larger than the first diameter. A peripheral surface of the first substantially cylindrical front portion 181a may be provided with recesses 185 adapted to cooperate with notches of the external module in order to lock an external module in the receptacle.

[0099] Preferably, the plurality of receptacle contacts 210a-d comprises: at least one receptacle contact for carrying power signals, and/or at least one receptacle contact for carrying data or control signals, and/or at least one receptacle contacts for carrying a power signal and a data or control signal. For example, contact 210b may be a DC power supply (e.g. 24 V), contact 210c may be a positive pole for a dimming protocol (e.g. DALI), contact 210a may be a general digital I/O (e.g. greater than 7 V), and contact 210d may be at the same time a negative pole for the dimming protocol, a ground for the power supply, a ground for the general digital I/O.

[0100] FIG. 7 illustrates a luminaire head with a housing H in which electrical components, such as a driver 710 and a PCB 720 with LEDs, are arranged. The luminaire housing H has an opening O, in which a receptacle assembly with a receptacle 100 and a gasket 400 is arranged. The front side 101 of the receptacle 100 faces the external module and the rear side 102 faces an inner space of the luminaire housing H. The gasket 400 is arranged partially between an outer surface of the housing H and a portion of the receptacle located outside of the housing H. The wires W (for reasons of simplicity only one line is drawn, but this line represents more than one wire) of the receptacle 100 are connected to the electrical components. As shown, the luminaire housing H may be configured to be attached to a pole P. FIG. 7 shows a so-called “side-entry” luminaire of a luminaire, but the skilled person understand that embodiments of the invention are equally applicable to other types of luminaire such as so called “post-top” luminaires where the pole extends below the luminaire housing or modular luminaires comprising a plurality of pole modules mounted one above the other.

[0101] FIG. 8 shows an example of a receptacle assembly 1000 comprising a receptacle 100 and a gasket 400. The gasket 400 is mounted between a housing (not shown in FIG. 8) and the receptacle 100 and in a predetermined relative angular position with respect to the receptacle 100, for example in a manner as explained above. In the embodiment of FIG. 8, the gasket 400 comprises a lip 411 which functions as the indicator means 410.

[0102] FIG. 8 shows an external module 500. The external module 500 comprises a shell protecting inner elements from external influences such as water and dirt. The shell has a lower end which at least partially covers the receptacle 100 when the external module 500 is mounted on the receptacle 100. Particularly in such embodiment, it is advantageous to form the indicator means 410 as a lip 411 extending outward from the gasket 400 such that it protrudes beyond the shell when the external module 500 is mounted on the receptacle 100. This is illustrated in FIGS. 8B and 8C. Mounting of the external module 500 onto the receptacle 100 typically requires a two-stage movement. Firstly, the external module 500 is moved towards the receptacle 100 by a translational movement of the external module 500 along the central axis A of the receptacle 100. This corresponds to moving from FIG. 8A to FIG. 8B. Secondly, the external module 500 is rotated with respect to the receptacle around the central axis A. This corresponds to moving from FIG. 8B to FIG. 8C.

[0103] The indicator means 410 is particularly relevant in the second stage of the movement. To this end, the external module 500 preferably comprises a further indicator 530 which is arranged to be aligned with the indicator means 410 when the external module 500 is correctly mounted onto the receptacle 100.

[0104] When the external module 500 comprises an RFID tag or reader which is to be aligned with a corresponding RFID reader or tag at the receptacle 100, the angular position of the indicator means 410 with respect to the receptacle 100 corresponds to the angular position of the further indicator 530 with respect to the external module 500 such that the RFID elements are aligned wen the indicators 410 and 530 are aligned.

[0105] FIGS. 9A and 9B show another embodiment wherein the external module 500 is mounted substantially on top of the receptacle 100 without extending over the receptacle 100. In FIG. 9A, the indicator means 410 is formed on a lip 411 of a gasket 400. The further indicator 530′ is aligned with the indicator means 410 for correct mounting of the external module 500. FIG. 9B shows another embodiment wherein the indicator means 410′ is arranged on the receptacle 100. In particular, the indicator means 410′ is formed as a sticker or a label positioned on a side surface of the receptacle 100. Because in this embodiment the external module 500′ does not extend over the receptacle 100, the side surface of the receptacle 100 is still visible when the external module 500′ is mounted. For correct mounting of the external module 500′, the indicator means 410′ and the further indicator 530′ are aligned. In yet another embodiment, the indicator means may be provided on the housing, preferably at a position which is close to the opening in the housing. In an exemplary embodiment, the receptacle, and in particular the rear portion thereof, may be provided with a flat portion on the peripheral wall between the front side and the rear side to ensure a proper alignment of the receptacle with respect to the opening in the housing. The opening in the housing may preferably be provided with a corresponding flat portion. In such an exemplary embodiment, the indicator means may be provided on the housing at a position which is close to the flat portion of the opening in the housing, thereby also ensuring a proper alignment of the external module with respect to the receptacle. A further indicator may be provided to the external module. For correct mounting of the external module, the indicator means and the further indicator are aligned.

[0106] In the figures, the indicator means and the further indicator are shown as a simple visual mark. It will be clear that in some embodiments, one or both of the indicator means and the further indicator may be more “complex” and could for example further comprise an RFID tag or any other communication means (e.g. Bluetooth) or further comprise a “smart label” such as a QR code.

[0107] Whilst the principles of the invention have been set out above in connection with specific embodiments, it is to be understood that this description is merely made by way of example and not as a limitation of the scope of protection which is determined by the appended claims.