GB2366675A

GB2366675A - Removable electric mains socket tester

Info

Publication number: GB2366675A
Application number: GB0021952A
Authority: GB
Inventors: David Harris
Original assignee: KEW TECHNIK Ltd
Current assignee: KEW TECHNIK Ltd
Priority date: 2000-09-07
Filing date: 2000-09-07
Publication date: 2002-03-13
Also published as: GB0021952D0

Abstract

An electric socket tester (12), suitable for domestic three pin mains sockets, comprises a housing (14) having a rear face (16) with conductive pins (18, 20, 22) extending therefrom for inserting into corresponding socket outlet conductors (4, (6, 8). A front face (24) of the housing (14) has a plurality of light-emitting devices (26, 28, 30), such as light-emitting diodes, for indicating good and/or faulty wiring connections of the socket (2). The light-emitting devices (26, 28, 30) are arranged in a configuration, such as triangular, substantially conforming to that of the socket outlet conductors (4, 6, 8). Light-emitting diodes (26, 28, 30) may be provided, capable of illumination in two (red and green) colours or three (red, green and amber) colours, and may be arranged to flash.

Description

2366675 ELECTRIC SOCKET TESTER This invention relates to electric socket

testers.

5 Electric socket testers have been known for many years and generally. comprise a housing, such as of electrically insulating plastics material, having a rear face provided with contact pins extending therefrom for inserting into an electrical socket to be tested, and a front face 10 provided with a linear array of light-emitting devices, the number of light-emitting devices corresponding to the number of outlet conductors in the socket to be tested. Electrical circuit components are provided inside the housing.

In operation, one or more of the light-emitting devices are caused to be illuminated to provide a static display to indicate an electrical fault condition associated with one or more outlet conductors in a socket being tested.

In order to determine to which faulty outlet conductor or conductors a particular arrangement of illuminated and/or non-illuminated lightemitting devices relates, a diagnostic, or look-up table is provided, usually on the 25 front face of the tester. A user of the tester has to examine the linear pattern of illuminated and/or nonilluminated devices and then refer to the diagnostic table to find a matching pattern. The diagnostic table - 2 includes a written indication as to which, if any, outlet conductor or conductors in the socket being tested has or have a fault associated therewith. Such a diagnostic table, and reference thereto, is essential since the 5 linear array of light-emitting devices in itself provides no indication. as to which socket outlet conductor each light-emitting device relates.

Early forms of socket tester incorporated light-emitting 10 devices in the form of neon bulbs which were somewhat fragile in nature and of limited life. Such bulbs provided poor visibility in high ambient light conditions and the natural red colour of the illuminated neon bulbs could result in confusion, where an illuminated bulb 15 served to indicate a sound outlet conductor in a socket.

Recent socket testers have utilised a linear array of light-emitting devices comprising bright, high-visibility and durable light-emitting diodes (LEDs). Such LEDs can 20 be of dual colour, providing a red indication where a problem exists and a green indication for a sound condition. Such recent socket testers incorporate microprocessor controllers and can also include an audible tone generator, a continuous tone indicating a 25 sound socket and a warbling tone indicating a fault condition. A built- in self-test facility is also known to be provided for checking that the tester is functioning correctly.

Such recent socket testers suffer from a disadvantage in that they still require reference to a diagnostic, or look-up, table in order to identify to which fault condition a particular static display of LEDs relates. 5 Mains electric sockets commonly comprise three outlet conductors, namely live, neutral and earth conductors. It is known to provide static displays of a linear array of three LEDs, showing sequences of illuminated and/or 10 non-illuminated LEDs involving single or dual coloured (red/green) LEDs. Typical wiring conditions of a socket.

which can be indicated are:

1. correct wiring 2. Reversed wiring to live and earth outlet 15 conductors 3. Reversed wiring to live and neutral outlet conductors 4. A neutral outlet conductor fault 5. An earth outlet conductor fault 20 6. A live outlet conductor fault 7. A missing wiring connection to a live outlet conductor It is an object of the present invention to overcome or 25 minimise the disadvantage of requiring a diagnostic, or look-up, table.

According to the present invention there is provided an electric socket tester for testing an electric socket having a plurality of socket outlet conductors accessible at a front surface thereof and connected to electrical 5 wiring, the tester comprising a housing having a rear face with a plurality of electrically conductive pins extending therefrom for inserting into corresponding socket outlet conductors of the socket, the housing further having a front face provided with a plurality of 10 light-emitting devices for indicating sound and/or faulty wiring connections to the socket, and wherein the lightemitting devices are arranged in a geometrical configuration substantially conforming to that of the socket outlet conductors as viewed on the front surface 15 of the socket.

The electric socket may have three socket outlet conductors which may be arranged in a substantially triangular configuration, three lightemitting devices 20 being provided, which may be arranged in corresponding substantially triangular configuration.

The triangular configuration of the three socket outlet conductors may comprise an upper earth outlet conductor, 25 a lower left neutral outlet conductor and a lower right live outlet conductor, the light-emitting devices in their substantially corresponding triangular configuration being each positionally related to a corresponding earth, neutral or live outlet conductor.

The light-emitting devices may comprise light-emitting 5 diodes (LEDs).

The light-emitting diodes (LEDs) may be arranged to be selectively illuminated in at least two colours, particularly red and green.

The light-emitting diodes (LEDs) may be arranged to be selectively illuminated in three colours, particularly red, green and amber.

15 The light-emitting devices may be arranged to flash for indicating one or more fault conditions of the electric socket.

The front face of the housing may be provided with 20 printed identifiers adjacent the light-emitting devices. Such printed identifiers may comprise words or symbols relating to the respective socket outlet conductors with which the light-emitting devices are associated.

25 A diagnostic, or look-up, table may additionally be provided on the front face of the housing, showing a sequence of illumination and/or nonillumination of the light-emitting devices for a sound condition and for each fault condition of the electric socket.

Audible warning means may additionally be incorporated in 5 the housing for providing audible indication of correct and/or faulty wiring connections to the socket. Such audible indication may comprise either a continuous tone signal or a warbling signal.

10 A microprocessor controller may be provided in the housing.

By means of the present invention, the provision of the light-emitting devices in a geometrical configuration 15 substantially corresponding to that of the outlet conductors of an electric socket being tested enables a user to immediately identify and locate any outlet conductor which has a wiring fault associated therewith, without immediate recourse to the use of diagnostic, or 20 look-up, tables. However, such diagnostic, or look-up, tables may be provided as a complete aid to the use of the tester.

The option of providing flashing light-emitting devices 25 draws immediate attention to dangerous fault conditions and especially where a particular pair of flashing red lights can immediately indicate a serious wiring 7 reversal, such as a reversal of the wiring to the live and earth outlet conductors of a socket.

The further option of providing light-emitting diodes 5 (LEDs) which can be selectively illuminated in red, green or amber colours, allows other fault conditions such as open circuit, neutral or earth fault, to be identified in amber, while retaining the use of red to indicate reversed connections.

For a better understanding of the invention and to show more clearly how it may be carried into effect, reference will now be made, by way of example, to the accompanying drawings in which:

Figure 1 is a front view of a mains electric socket to be tested; Figure 2 is a perspective rear view of an embodiment of 20 an electric socket tester according to the present invention; and Figure 3 is a front view of the electric socket tester of Figure 2.

Referring to Figure 1, a mains electric socket 2 to be tested has three socket outlets 4, 6, 8 accessible at a front surface 10 thereof and connected to electrical wiring (not shown) incorporating live, neutral and earth leads. The three socket outlets 4, 6, 8 are arranged in standard, well known, substantially triangular configuration at the front surface 10 of the socket 2.

5 Upper socket outlet 4 is an earth socket outlet, lower left socket outlet 6 is a neutral-socket outlet and lower right socket outlet 8 is a live socket outlet.

Referring to Figures 2 and 3, an electric socket tester 10 12, for testing the electric socket 2 of Figure 1 to ensure correct wiring thereof, has a housing 14, suitably of rigid plastics material, or other suitable electrically insulating material. The housing 14 has a rear face 16 with three electrically conducting pins 18, 15 20, 22, such as of brass or other suitable metal, extending therefrom and configured for inserting into corresponding socket outlet conductors 4, 6, 8 in the socket 2.

20 The housing 14 has a front face 24 provided with three light-emitting diodes (LEDs) 26, 28, 30 which are intended for producing visual indication of sound or faulty wiring connections to the outlet conductors 4, 6, 8 of the socket 2. In the illustrated embodiment the 25 LEDs 26, 28, 30 are connected to, and controlled for operation by, a microprocessor controller (not shown) which is arranged inside the housing 14 and which is also connected to the pins 18, 20, 22 extending from the rear face of the housing.

The LEDs 26, 28, 30 are arranged in a triangular 5 configuration substantially conforming to that of the socket outlet conductors 4, 6, 8 of the socket 2 as viewed on the front surface 10 thereof.

From the triangular configuration of the LEDs 26, 28, 30, 10 it is immediately clear to a user of the socket tester 12 that the LED 26 relates to the earth socket outlet 4, the LED 28 relates to the neutral socket outlet 6, and the LED 30 relates to the live socket outlet 8. However, further identification can be provided on the front face 15 24, beside the LEDs 26, 28, 30, such as a letter E and/or an electrical earth symbol, a letter N and a letter L, respectively.

The socket tester 12 may be provided in a simple form in 20 which one or more of the LEDs 26, 28, 30 is or are illuminated in green colour to indicate one or more good or sound wiring connections in the socket 2, while one or more faulty connections in the socket 2 is indicated by one or more unlit LEDs 26, 28, 30.

For example, if the wiring to all three socket outlets 4, 6, 8 is correct, then all three LEDs 26, 28, 30 will be illuminated green.

- 10 If the wiring to the live socket outlet 8 and the earth socket outlet 4 is reversed, this fault condition will be indicated by the LEDs 26 and 30 being unlit, while the LED 28 is illuminated green to indicate that the neutral 5 socket outlet 6 is wired correctly.

If there is a fault in the wiring to the neutral socket outlet 6, this will be indicated by the LED 28 being unlit, while the LEDs 26 and 30 are illuminated green to 10 indicate that the earth socket outlet 4 and the live socket outlet 8 are wired correctly.

If there is a fault in the wiring to the earth socket 4, this will be indicated by the LED 26 being unlit, while 15 the LEDs 28 and 30 are illuminated green to indicate that the neutral socket outlet 6 and the live socket outlet 8 are wired correctly.

If there is a fault in the wiring to the live socket 20 outlet 8, or for some reason there is no connection of the live lead to the socket 2, all three LEDs 26, 28, 30 will be unlit.

The sequences of lit and/or unlit LEDs 26, 28, 30 in 25 respect of the various identified fault conditions of the socket 2 may be conveniently set out, if required, in a diagnostic, or look-up, table 32 which can be arranged in printed form on the front face 24 of the housing 14.

- 11 The socket tester 12 may be enhanced by providing for the LEDs 26, 28, 30 to be each capable of being selectively illuminated in green or red colours. With such an arrangement, which may be preferred, apart from a fault 5 condition where there is no connection of the live lead to the socket 2, resulting in all three LEDs 26, 28, 30 being unlit, all the previously described fault conditions will be indicated by red illuminated, rather than unlit, LEDs. The provision of the red illuminated 10 LEDs highlights serious fault conditions, such as those involving reversal of the wiring to the live 8 and earth 4 socket outlets.

In a further enhancement of the socket tester 12, the 15 LEDs 26, 28, 30 can be each capable of being selectively illuminated in green, red, or amber, colours. This enables less serious fault conditions to be indicated by illumination of one or more amber, rather than red, LEDs. For example, a fault condition where there is a fault in 20 the wiring to the neutral socket outlet 6, while the wiring to the earth 4 and live 8 socket outlets is sound, could be indicated by amber illumination of LED 28, while LEDs 26 and 30 are illuminated in green.

25 Furthermore, a fault condition where there is a fault in the wiring to the earth socket outlet 4, while the wiring to the live 8 and neutral 6 socket outlets is sound, - 12 could be indicated by amber illumination of LED 26, while LEDs 28 and 30 are illuminated in green.

In a further enhancement of the socket tester 12, 5 whenever there is a fault condition, all three LEDs are arranged to flash in their selected colour or colours, in order to provide additional warning of the fault condition. When there is no fault in the socket 2, as indicated by all three LEDs 26, 28, 30 being illuminated 10 green, the flashing mode may be omitted, since there is no action required to rectify a fault.

An audible warning arrangement (not shown) can also be included in the housing 14 of the socket tester 12. This 15 can operate to provide a continuous tone signal when there is no fault in the wiring to the socket 2, and a warbling signal when there is a fault condition. If there is no connection of the live lead to the socket 2, no audible signal will be provided.

- 13

Claims

1. An electric socket tester for testing an electric socket having a plurality of socket outlet conductors 5 accessible at a front surface thereof and connected to electrical wiring, the tester comprising a housing having a rear face with a plurality of electrically conductive pins extending therefrom for inserting into corresponding socket outlet conductors of the socket, the housing 10 further having a front face provided with a plurality of light- emitting devices for indicating sound and/or faulty wiring connections to the socket, and wherein the lightemitting-devices are arranged in a geometrical configuration substantially conforming to that of the 15 socket outlet conductors as viewed from the front surface of the socket.

2. A socket tester as claimed in claim 1, wherein the electric socket has three socket outlet conductors and 20 three light-emitting devices are provided on the front face of the housing.

3. A socket tester as claimed in claim 2, wherein the three socket outlet conductors are arranged in a 25 substantially triangular configuration and the three light-emitting devices are arranged in corresponding substantially triangular configuration on the front face of the housing.

- 14 4. A socket tester as claimed in claim 3, wherein the triangular configuration of the three socket outlet conductors comprises an upper earth outlet conductor, a lower left neutral outlet conductor and a lower right 5 live outlet conductor, the light-emitting devices in their substantially corresponding triangular configuration being each positionally related to a corresponding earth, neutral or live, outlet conductor.

10 5. A socket tester as claimed in any preceding claim, wherein the light-emitting devices comprise lightemitting diodes (LEDs).

6. A socket tester as claimed in claim 5, wherein the 15 light-emitting diodes (LEDs) are arranged to be selectively illuminated in at least two colours.

7. A socket tester as claimed in claim 6, wherein the light-emitting diodes (LEDs) are arranged to be 20 selectively illuminated in red and green colours.

8. A socket tester as claimed in claim 6, wherein the light-emitting diodes (LEDs) are arranged to be selectively illuminated in three colours.

9. A socket tester as claimed in claim 8, wherein the light-emitting diodes (LEDs) are arranged to be selectively illuminated in red, green and amber colours.

- 15 10. A socket tester as claimed in any preceding claim, wherein the light-emitting devices are arranged to flash for indicating one or more fault conditions of the electric socket. 5 11. A socket.tester as claimed in any preceding claim, wherein the front face of the housing is provided with printed identifiers adjacent the light-emitting devices.

10 12. A socket tester as claimed in claim 11, wherein the printed identifiers comprise words or symbols relating to the respective socket outlet conductors with which the light-emitting devices are associated.

15 13. A socket tester as claimed in any preceding claim, wherein a diagnostic, or look-up, table is additionally provided on the front face of the housing, showing a sequence of illumination and/or nonillumination of the light-emitting devices for a sound condition and for each 20 fault condition of the electric socket.

14. A socket tester as claimed in any preceding claim, wherein audible warning means is additionally incorporated in the housing for providing audible 25 indication of correct and/or faulty wiring connections to the socket.

- 16 15. A socket tester as claimed in any preceding claim, wherein the audible indication comprises either a continuous tone signal or a warbling signal.

5 16. A socket tester as claimed in any preceding claim, wherein a microprocessor controller is provided in the housing.

17. An electric socket tester substantially as 10 hereinbefore described with reference to, and as shown in, the accompanying drawings.