GB2528162A

GB2528162A - A consumer unit for electrical power distribution

Info

Publication number: GB2528162A
Application number: GB1508018.7A
Authority: GB
Inventors: Stephen J Willis
Original assignee: Andrew Main Wilson; Gray Levett
Current assignee: Andrew Main Wilson; Gray Levett
Priority date: 2014-05-09
Filing date: 2015-05-11
Publication date: 2016-01-13
Anticipated expiration: 2035-05-11
Also published as: GB201408208D0; GB2528162B; GB2525919A; GB201508018D0

Abstract

A consumer unit 1 for control of an electrical power system comprises a housing 10, a main isolation switch 12, a local circuit breaker 14 connected to the main isolation switch and an emergency lighting unit within the housing having a power input connected to the local circuit breaker and comprising a power supply unit with a backup battery to power the emergency lighting unit, a power connection detector connected to the power input, a light source powered by the battery, a control means to control the light source in response to an output from the power connection detector and self-test means configured to test the function of the light source under control of the control means.

Description

A Consumer Unit for Electrical Power Distribution

Field of the Invention

The present invention relates to consumer units for protection and control of electrical power distribution systems, and in particular to such units comprising an emergency lighting capability.

Background

Consumer units for protection and control of electrical power supply systems usually comprise a main isolation switch -to control incoming current, a local residual current device (RCD) or other trip device (for detection of earth-leakage or other faults) and one or more independent circuit breakers to control local circuits for lighting and power.

In the event that a circuit breaker trips a user needs to gain access to the consumer unit to investigate and/or to reset a breaker or trip switch. Often the consumer unit is located in a dark or hard-to-access location, such as a cellar or under stairs cupboard, and in some cases there is no local lighting as its supply may have also tripped. In such circumstances it was advantageous for an independent emergency lighting system to be provided as part of the consumer unit to allow visibility.

Such emergency lighting is known in the art] and typically operates from its own back-up power supply and runs an emergency light source in response to a power failure.

However, sometimes it may have taken a user a considerable duration to find the consumer unit and respond to the tripped breaker. For example if the property or office was vacant over a weekend or holiday, the fault may only first come to light some considerable time later and as emergency lighting only has a limited battery lifetime, there was a risk that such batteries might have become depleted.

Also, it has to be remembered that most emergency lighting units were not designed to operate for long periods, often standing in a ready state for several years. There was therefore a risk that such back-up power supply systems might malfunction, for example through failure of a battery. Hence there has been an on-going need for a user to test the back-up power supply system periodically.

This often proved inconvenient or was simply forgotten. Furthermore in industrial or commercial settings such services added to maintenance costs.

At best most prior art devices only addressed these problems in a high-end, stand-alone, self-testing emergency lighting device.

Prior Art

Accordingly a number of attempts were made to resolve the problem and examples of devices developed are described in the following: Published International Patent Application WO-A-201 1085729 (Nordic Inwave APS) discloses: a battery operated emergency light device for installation in a breaker panel. In case of a power failure a light device was activated and illuminated the breaker panel and other components, as well as an area beneath the breaker panel.

This device is a light unit to be installed in an existing consumer unit, and comprises only a small battery owing to its configuration, so has the disadvantage that it will light as soon as the power supply is lost. It will need to be tested manually regularly to ensure its operation.

Published International Patent Application WO-A-20081 35961 (Eaton Industries) discloses an emergency illuminating device for installation within an electrical switchboard. The emergency illuminating device may have standard physical dimensions for installing in an electrical switchboard, a fuse box or the like and it may be activated during power failure to illuminate the switchboard.

The emergency illuminating device may also comprise a rechargeable power source that may be recharged when mains power is present.

Again, this is a small device adapted to be installed in an existing consumer unit, in this case in a standard slot as provided for a circuit breaker, with the same disadvantages as above. It comprises a test button to test the emergency light source, but this still needs to be done manually.

Published International Patent Application WO-A-2003092025 (Capon) discloses: a consumer unit comprising at least one current protection device.

The unit further comprises at least one light associated with the unit. The at least one light being operatively connected to the at least one protection device, whereby the at least one light is energised so as to illuminate the unit when the at least one protection device operates.

Once more this device has the disadvantages that it illuminates as soon as a power supply is lost and it needs to be tested manually and at regular intervals to ensure its operation.

Japanese Patent Application JP-A-2002345114 (Kawamura) discloses a safety lamp for use in power failures which can be easily deployed and enables a reduced sized distribution board to be used.

Japanese Patent Application JP-A-2003348717 (Kawamura) discloses a security lamp for service interruption. The lamp is arranged in a housing with an opening. The housing has a lid that is closable and permits access in order to replace a battery.

It is an object of the present invention to provide an improved consumer unit for protection and control of electrical power distribution systems which does not suffer from the aforementioned disadvantages.

Summary of the Invention

According to a first aspect of the present invention there is provided a consumer unit comprising: a circuit breaker; a local emergency lighting unit with light source; a power supply; and a self-test means to test the emergency lighting unit.

Typically the consumer unit comprises: at least one circuit breaker (or isolation switch); an integral emergency lighting unit with light source; a back- up battery power supply; automatic night-time proximity detection -for auto-illumination; and a self-test means to test the emergency lighting unit.

Ideally the consumer unit includes a mains circuit breaker and at least two sub-circuit or local circuit breakers.

Preferably the integral power supply unit comprises a rechargeable back-up battery.

In an alternative embodiment the invention provides a consumer unit comprising: a housing; a local circuit breaker within the housing connected to the main switch; and an emergency lighting unit within the housing having a power input connected to the local circuit breaker, comprises: a power supply unit to power the emergency lighting unit; a rechargeable battery to power the unit] connected to the power supply unit; a power connection detector connected to the power input; a light source powered by the battery; a control means to control the light source in response to an output from the proximity detector; and a self-test means configured to test the function of the light source and the battery charging circuit, under control of the control means.

This is the first occasion that a consumer unit includes the following features in a single unit. The features are: a) Consumer Unit b) Self-testing Emergency Lighting device c) Self-illuminating unit lighting via a built-in proximity sensor d) An audible alert indicating: i. Total power failure or local circuit failure; and/or ii. Faulty emergency lighting equipment.

Preferably a power supply unit comprises at least one sensor arranged to power the emergency lighting unit upon sensing a condition.

In some embodiments the power input is connected to a local circuit breaker.

It is also understood that the present invention is applicable in breaker panels closed off by a panel door by providing a secondary emergency light device mounted on the outside of the breaker panel door, whereby the area around the breaker panel can be illuminated.

In another embodiment the self-test means may include a means for measuring electric current flowing to the light source so as to provide an indication of power consumption.

In some embodiments the self-test means may comprise a means to measure electrical continuity through the light source, thereby providing an indication of a defective light source or blown or broken lamp.

In some embodiments the self-test means may comprise a light sensor configured to measure the light output of the light source, thereby providing a an indication as to whether the light is working.

In some embodiments the light unit comprises a battery test means to test the battery under control of the control means. The self-test means may include a means to measure and/or test the functionality of a back-up battery or other power supply. In the case of a battery its ability to hold its charge may also be tested as well as its stored energy and therefore its capability to power the unit for a minimal specified duration. This minimal duration may vary in different regions or jurisdiction.

For example in the United Kingdom the minimum duration is 2 hours. Means may also be provided for automatic testing of the battery back-up battery or other power supply at regular intervals. A reporting module may optionally be included. This is ideally a telemetric device that is adapted to transmit a status signal to a remote recipient or device so as issue an alert in the event of a failure or imminent risk of failure of a back-up battery or power supply or light source.

In some embodiments the battery test means is configured to test the battery voltage and/or current. For example in a specified test condition imposed by the battery test means.

In this way the device provides a consumer unit having a built-in emergency light source, powered by a rechargeable battery that is kept charged from a power connection that supplies a local circuit breaker.

Preferably the local circuit breaker is connected to the lighting circuit that is local and connected to the consumer unit. In the case that the local or allocated circuit breaker trips (or there is a loss of supply to the consumer unit), the emergency light source is illuminated by the control means. This allows the user to locate and to re-set the circuit breaker as appropriate, as well as alert the user to the fact that a general power outage or disruption to supply has occurred.

In the case that the local circuit breaker, to which the emergency lighting unit is connected, trips but the main circuit breaker or main switch remains on, the emergency light source is automatically illuminated by a control means -via the rechargeable battery.

It is therefore advantageous to use a local circuit breaker for lighting local to the consumer unit. If another local circuit breaker trips, then lighting local to the consumer unit is still powered, and the emergency lighting unit does not illuminate as it is not needed in these circumstances. However, if necessary the built-in proximity sensor may still illuminate the consumer unit, during hours of darkness so as to illuminate various circuit breakers.

In alternative embodiments the emergency lighting unit comprises an ambient light sensor configured to sense the ambient light level in the vicinity of the consumer unit. Optionally the emergency lighting unit is configured to control the light output of the light source in response to the ambient light level in the vicinity of the consumer unit.

Preferably the lighting unit comprises a motion or presence sensor, such as a passive infra-red (PIR) device, to detect a user in the vicinity of the consumer unit. In some embodiments the motion or presence sensor comprises one of a microwave sensor, an infra-red sensor, an ultrasonic sensor or a capacitance sensor. Advantageously the lighting unit is configured to enable the light source to be lit in response to the output from the sensor. In this way the emergency lighting unit is configured to save energy in the battery and to adjust the power consumption to suit existing light levels and the presence of a user.

In an alternative embodiment a lighting unit comprises an audible alarm or sounder to provide an audible signal in the event of one or more of a power failure and/or a failure detected by the self-test process.

In some embodiments the lighting unit comprises a sounder test means to test the sounder or audible alarm. In some embodiments the sounder test means comprises means to test current flowing to the sounder under test conditions.

In another embodiment the sounder test means may include a microphone to detect sound from the sounder. An advantage of this is that the microphone permits a person to speak instructions into a voice recognition device so that systems may be switched or re-booted or tested without having to touch a particular switch, thereby enabling a person who may not be able to see the panel to activate it.

In some embodiments the emergency lighting unit comprises: a control button configured to test the unit when the button is pressed, for example to activate one or more of a light source test means such as at least one status indication light emitting diode (LED5), a battery test and a sounder test. In some embodiments the unit is configured to cancel an alarm when the control button is pressed.

In some embodiments the sensitivity of one or both of the presence detector and/or the ambient light sensor are adjustable.

According to a further aspect of the present invention there is provided a system comprising a consumer unit as described herein and a lighting circuit for lighting local to the consumer unit connected to the same local circuit breaker as the emergency lighting unit.

Ideally the unit performs at least the following: 1) monitors that there is a constant mains supply; 2) regularly self-checks the emergency lighting unit; 3) regularly self-checks the battery and its ability to be charged and store charge; 4) regularly self-checks the sounder (audible alarm); 5) determines ambient light level; and 6) if the ambient light levels is sufficiently low determines the proximity of a person and activates the emergency lighting to permit visibility to a user for example when approaching the consumer unit.

In an alternative embodiment, if a user activates a test/silence button' for more than a predetermined duration (for example 3 seconds), the system performs an instant and perfunctory self-test and self-diagnostic action. So that all the warning LEDs, the sounder, battery and any white emergency LEDs are all tested in series in real time so as to be observed by a user.

According to a further aspect of the present invention there is provided a system for emergency lighting an electrical consumer unit using a consumer unit as described herein comprising: a detecting means that detects a power connection to a local circuit breaker within the consumer unit; and a control means for supplying current to a light source mounted on or adjacent to the consumer unit in response to the said detection.

In some embodiments the local circuit breaker is connected to a lighting circuit local to the consumer unit.

In an alternative embodiment there may be an electrical output from a consumer unit circuit board for additional, yet remote, associated lighting slave units.

It is appreciated that aftermarket' retro-f it devices may be provided for use with an existing consumer unit, so that an electrician can adapt or update a consumer unit to one according to the present invention. Such adaptation may be in the form of comprise a replacement lid or cover or back-box.

A system according to the present invention is therefore designed for connecting into one existing and local lighting circuit breaker, so that no extra circuit breaker location or space' needs to be allocated within a standard consumer unit. In addition or the alternative within another embodiment, an independent and dedicated miniature circuit breaker (MGB) may be used to constantly supply power to the system.

Optionally a built-in combination of heat and smoke detection is provided.

This can be controlled in such a manner that both detection systems may be operated independently of one another or simultaneously.

An audio alarm may be provided. The modified system may also be configured to alert people by flashing an optional lighting system.

Ideally a means is provided to shut off a power supply to the consumer unit, for example by tripping its RCD safety mechanisms. Such features not only alert the user to a potential hazard but also reduce risks of a fire and is particularly useful if the user is away from the property, distracted by loud music or asleep.

There is also provided a self-test feature and a means to silence alarms and switch of flashing lights. This feature may be local or able to be performed remotely -for example view a telemetric or wireless link. Optionally it may be provided by way of application specific software (a so-called APP) operating on a mobile communication device -such as a mobile telephone (cellphone).

Optionally heat and smoke detectors may have an access point wherein service companies or a fire service authority can connect dedicated devices, such as wireless communication devices, for unification of alarm activation and call out services. Optionally the sensor may switch off the supply to the consumer unit.

It is therefore appreciated that the system has the ability to be activated (illuminate or issue an audible warning) by any predetermined electrical circuit using wireless technology. A separate transmitter (connected to a specific circuit) and built-in receiver may be used to communicate a specific circuit fault or power failure to one or more remote recipients.

Preferred embodiments of the invention will now be described, by way of examples only, and with reference to the Figures in which:

Brief Description of Figures

Figure 1 shows a front view of an embodiment of a consumer unit according to the invention; Figure 2 shows an isometric view of the embodiment in figure 1 with the front cover closed; Figure 3 shows an isometric view of the embodiment shown in figure 2 with the front cover open; Figure 4 shows an exploded isometric view of the embodiment shown in figure 3; Figure 5 shows a block diagram of an embodiment of the invention; Figure 6 shows a functional diagram of a system that includes an embodiment of the invention; Figure 7 shows schematic diagram of another embodiment of the invention; Figure 8 shows a rear view of a consumer unit; Figure 9 show an overall view of another embodiment of the invention referred to as the circuit safe Guard Watch'; and Figure 10 shows an overall diagrammatic view of the portable circuit safe Guard Watch'.

Detailed DescrirMion of Figures Referring to figures 1 to 5, an embodiment of a consumer unit 1 according to the invention is shown. The consumer unit 1 comprises: a housing 10, a main isolation switch 12 located within the housing and connected to an incoming power supply 13 (see Figure 5). A local circuit breaker 14 is provided in the housing 10 and is connected to a main switch/circuit breaker.

Referring to Figure 5 an emergency lighting unit 16 is shown which may have intumescent fire seals around its various openings; such as the cable exits, MCB positions or compartmented electronic components. The housing has a power input 18 connected to the local circuit breaker 14, comprising: a power supply unit 20 to power the emergency lighting unit 16 and a battery 22 for supplying current to the emergency lighting unit 16. Connected to the power supply unit 16 is a power connection detector 24 which is connected to an input 18.

A light source 26/70 is powered by the battery. A control means 28 controls the light source 26/70 in response to an output from the power connection detector 24. A self-test means 30 is configured to test the function of the light source 26/70 under control of the control means 28. The self-test means 30 comprises a means 31 to measure current flowing to the light source 26/70.

In alternative embodiments the self-test means 30 may comprise a light sensor 32 configured to measure the light output of the light source. The lighting unit 16 comprises battery test means 34 for testing the battery under control of the control means 28.

The battery test means 34 tests: the battery voltage and/or a current delivered by the battery. In the embodiment shown in Figure 5, local circuit breaker 14 is connected to the lighting circuit 36 which is located close to a consumer unit 38 that supplies power to local lighting unit 16. The lighting unit 16 comprises an ambient light sensor 40 configured to sense the light level in the vicinity of the consumer unit 38 and to provide a signal to the control means 28 for controlling the light output of the light source 26/70 in response to a low light level signal in the vicinity of the consumer unit 38.

In the embodiment shown in 5 the lighting unit 16 comprises a movement or presence sensor 42 for detecting the presence of a person in the vicinity of the consumer unit. Presence sensor 42 is a passive infra-red (PIR) device.

In one mode of operation, when all of the following occur: disconnection/loss of the power supply (by detector 24); and a user is detected by the presence sensor 42; and the ambient light level falls below a threshold value, the emergency lighting unit 16 is switched to light the light source 26/70.

In the embodiment shown in Figure 5 the lighting unit comprises a sounder 44 to provide an audible signal in the event of one or more of a power failure and a failure detected by the self-test process and a sounder test means 46 to test the sounder, the sounder test means comprises means to test current flowing to the sounder under test conditions.

In some versions of the embodiment the sounder test means comprises a microphone 48 to detect sound from a person -for example in order to sense the presence of a person or to respond to voice commands in accordance with voice recognition software.

In this embodiment the emergency lighting unit comprises a control button 50 configured to test the unit when the button is pressed, for example to activate one or more of a light source test, a battery test and a sounder test, and to cancel an alarm resulting from either a power failure or a failure of one or more self-test means when the control button is pressed. The embodiment also comprises an indicator unit 52 comprising indicators for battery charge, a power supply fault (i.e. a circuit breaker has tripped) and a fault condition within the emergency lighting unit.

In the embodiment shown in Figures 2 and 3 the housing 10 comprises a housing body comprising a housing body front 62 and a housing body rear 64 housing portions, and a lid 66 to close the housing, hinged to the housing body front 62 at hinge position 68 such that it may open downwards to allow access to the circuit breakers.

The emergency light source comprises a plurality of white light emitting diodes (LED5) provided in a strip subassembly 70 as known in the art of LED lighting, at a position 72 adjacent to the circuit breakers, behind a diffuser 74 mounted on the front housing portion. In this way the emergency lighting illuminates both the circuit breakers and the vicinity of the consumer unit as a whole.

The lid 66 and the housing body front 62 are configured such that the lid may fold up into a recess 76 (Figure 3) formed in the housing body front 62 to provide a flush appearance of the two, and may be secured in place for example by a click-stop or a catch. The lid 66 is both accessible for ease of maintenance and acts as a fire guard (along with an intumescent seal) from the main consumer unit.

In Figure 1 the consumer unit 1 comprises a housing body front 62 having a sound outlet grille 78 for the sounder an aperture 80 for the ambient light sensor and a push button control 50 as described previously.

The indicators forming part of the indicator unit are provided also behind the diffuser at a position 82 to one side of the emergency lighting LEDs. Access points to allow sensitivity adjustment for the ambient light sensor and the presence detector are provided behind the diffuser at a position 84 to one side of the emergency lighting LEDs, and the diffuser is configured to be removable from the front housing portion to allow access to them.

The presence detector is also provided on the front housing portion to detect a user in front of the consumer unit.

Additional warning LEDs, in red, green, yellow and blue colours, illuminate at various times to indicate the state-of-play of the consumer unit for example; green = system OK, red = power failure, flashing yellow = system fault, blue = system in self-test mode.

Referring to Figure 4 the components of the embodiment are shown in exploded form, in order from front to rear there is shown a lid 66 and a diffuser 74. Blanking plates 86 cover unused positions for circuit breakers. A housing body front 62 has hinged positions 88 such that the lid 66 may snap into place and an aperture 90 receives the circuit breakers. The LED light strip 70 comprises LED light sources (not shown in Figure 4). The strip mounts onto the underside of the upper edge of the recess 76 as shown as position 72.

The indicator unit 52 comprising three or four indicator LEDs, which are mounted adjacent LED light strip 70 at position 82. A circuit board 92 includes circuitry for providing control and a control means which are shown in detail in Figure 5.

An audible alarm or other sounder 44, an ambient light sensor 40, a user control button 50 and a power supply unit 20 connected to the circuit board.

The battery 28 is retained by clips. Fixtures 94 are for attaching the circuit board and battery 28 to a backboard or wall. An emergency lighting unit cover 96 optionally contains control circuitry, a main isolation switch 12 and a circuit breaker 14. A circuit breaker mounting rail 98 includes a power connection terminal strip 100. Housing body rear 64 comprises a moulded mounting fixtures 102.

In this way the emergency lighting unit is provided within the housing above the level of the circuit breakers and separated from them.

With reference to Figures 6 and 7 the system 1000 (comprising the consumer unit in use) may incorporate further circuitry and functionality, some of which is described below with reference to Figure 9.

Figure 6 shows an embodiment with a basic electrical diagram which may include a wired version.

Referring to Figures 8, 9 and 10 there are shown different views of another embodiment of the invention referred to as the circuit safe pro'. Like parts bear the same reference numerals as the other Figures.

The embodiments shown ideally operates with the UK-only Regulation 421.1.201, so that requirements of British Standards BS EN 61439-3 (Distribution Boards) are complied with. The housing or enclosure is manufactured from non-combustible material. Alternatively the housing is enclosed in a cabinet or constructed of non-combustible material.

Figures 9 and 10 show an overall diagrammatic view of another embodiment of a system that incorporates fire detection, fire seals and wireless interactivity.

In another embodiment the system which can be installed using magnets, within existing metal consumer units or distribution boards, and then hard-wired into the local lighting circuit. Optionally an RCD may be included in combination with a heat and/or smoke detector, the RCD being configured to trip on detection of either excess heat or excess smoke.

Furthermore to meet the requirements of Regulation 421.1.201, there is an added 30 minute inner intumescent fire seal provided to control any potential smoke leakage. Therefore in the event that the contents of the consumer unit reaches a certain temperature, the intumescent fire seal expands, so restricting/blocking the escape of smoke and fumes.

In addition to the aforementioned features, separate lighting sections may be required. The embodiments shown may be incorporated and stored within a suitable metal consumer unit or metal housing, whilst the lighting (LED or electroluminescent strips) and audio indications are able to be repositioned in and around the enclosures.

Another optional feature is the inclusion of a so-called smart-meter module.

This can be part of the main consumer unit or provided in a separate unit, via, a USB or a wireless (such as Bluetooth) link. The monitoring device may be built in to the main isolation switch where data is analysed. Alternatively it can be displayed by a separate unit. Using home WiFi networks enables the data to be sent to data-receiving central monitoring stations.

This eliminates the current concerns of current smart meters' being carcinogenic and emitting unshielded signaling (dirty-electricity) using the incoming mains supply. Use of WiFi and/or 4G enables the consumer to monitor power consumption at a remote location.

The emergency lighting is not limited to LEDs but also includes electroluminescent technology including light emitting capacitor (LEC).

It produces light when phosphor crystals are excited by being exposed to electric current. Electroluminescent (EL) panels and strips can be found as backlighting for LCDs in pagers, cell phones, watches, and control panels as well as strip lighting for egress, decor architecture, broadcast sets, and much more. Electroluminescent (EL) technology offers many benefits, including the following: Items can be seen at greater distances than point source lamps in dark conditions.

The material from which they are formed is flexible.

They are cool to the touch They are thin They do not impair night vision They have very low energy consumption requirements There is no filament and so they cannot fail in the same way as a lamp They are relatively maintenance free They do not contain any hazardous materials.

Referring now to Figures 9 and 10 which shows an overall diagrammatic view of another embodiment of the invention referred to as the Guard Watch'. This stand-alone (and consumer unit free) system can be erected either remotely from, or local to an existing consumer unit and then hard-wired into the local lighting circuit. The unit utilises the aforementioned design but is designed to be positioned in any chosen location to observe and protect.

The embodiments shown in Figures 9 and 10 have the following features: Smart-Metering I Self-Metering Reading module Monitoring of dual power -photovoltaic installations (solar panel system) Self-monitoring of all individual circuits Self-calibration Self-diagnostics -(self-metering/testing) Time & Date Memory Log Data analysis Hand-held emergency device/panic alarm module Pre-programmable circuits (various attributes; Lighting, Smoke, Freezer) Connected to a 24-hour central monitoring station Central Station remote over-ride control Smoke detection within the housing Heat detection within the housing Separate remote-control RCD protection Separate remote-control MCB protection Emailed/texted basic status reporting -module plug-in RFI & EMF electrical interference noise filtering -module plug-in Anti-surge protection -module plug-in Built-in self-testing emergency lighting unit (LED or electroluminescent technology) Back-up battery for emergency signal transmissions Proximity-controlled control ilium ination facility Engineer & User Access Codes USB data retrieval and upload capabilities Wireless interface port for monitoring of specific outlets Wireless interface port for syncing with existing fire detection devices Remote User Keypads -wired & wireless Base-sound' technology (a future ability to extinguish fire using low resonance sound between around 30-60Hz) Auto-disconnection of the consumer unit supply on the confirmation of a potential fire within Latest British Standards Regulations consumer unit housing Additional inner intumescent fire seals to control any potential smoke and fume leakage NFC (Near Field Communication) for smart data downloads to a mobile device.

Bespoke plug-in units to communicate with other manufactures products; Smoke detection UPS -Uninterrupted Power Supplies Remote socket outlets or plug-through devices for appliance monitoring Emergency devices Home Automation X-1O Sync capabilities Various off-grid systems General signaling devices Self-testing of circuits: RCD test Earth-fault Loop Electrical noise Incoming electrical monitoring/testing The invention has been described by way of examples only and it will be appreciated that variation may be made to the above-mentioned embodiments without departing from the scope of invention. Firstly it will be understood that any features described in relation to any particular embodiment may be featured in combinations with other embodiments.

With respect to the specification therefore, it is to be realised that the optimum dimensional relationships for the parts of the invention, to include variations in size, materials, shape, form, function and manner of operation, assembly and use, are deemed readily apparent and obvious to one skilled in the art, and all equivalent relationships to those illustrated in the drawings and described in the specification are intended to be encompassed by the present invention.

Therefore, the foregoing is considered as illustrative only of the principles of the invention, with variation and implementation obvious and clear on the basis of either common general knowledge or of expert knowledge in the field concerned.

Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention as set out in the accompanying claims.

Claims

Claims 1. A consumer unit comprising: a circuit breaker; a local emergency lighting unit with light source; a power supply; and a self-test means to test the emergency lighting unit.
2. A consumer unit as claimed in claim 1, comprising: a housing and a main isolation switch within the housing.
3. A consumer unit as claimed in claim 2 wherein the local circuit breaker is connected to the main isolation switch and/or an RCD device.
4. A consumer unit as claimed in any preceding claim wherein the emergency lighting has a power input connected to the local circuit breaker.
5. A consumer unit as claimed in any preceding claim wherein a battery power supply is provided to power the emergency lighting unit and a control means is provided to control the light source in response to an output from a power connection detector and a self-test means is configured to test the function of the light source under control of the control means.
6. A consumer unit according to claim 2, wherein the power input is connected to the local circuit breaker.
7. A consumer unit according to claim 3, wherein the local circuit breaker controls the lighting circuit for lighting local to the consumer unit.
8. A consumer unit according to any preceding claim wherein the self-test means comprises means to measure the current flowing to the light source.
9. A consumer unit according to any preceding claim wherein the self-test means comprises means to measure electrical continuity through the light source.
1O.A consumer unit according to any preceding claim wherein the self-test means comprises a light sensor configured to measure the light output of the light source.
11.A consumer unit according to any preceding claim wherein the emergency lighting unit comprises battery test means to test the battery.
12.A consumer unit according to claim 8, wherein the battery test means is configured to test one or more of the battery voltage and current delivered by the battery.
13.A consumer unit according to any preceding claim wherein the emergency lighting unit comprises an ambient light sensor configured to sense the ambient light level (lux levels) in the vicinity of the consumer unit.
14.A consumer unit according to any preceding claim wherein the emergency lighting unit comprises a movement or presence sensor to detect a user in the vicinity of the consumer unit.
15.A consumer unit according to any preceding claim wherein the emergency lighting unit comprises a sounder to provide an audible signal in the event of one or both of a power failure and a failure detected by the self-test process.
16.A consumer unit according to any of claims 1 to 11 wherein the emergency lighting unit comprises sounder test means to test the sounder.
17. A consumer unit according to claim 16 wherein the sounder test means comprises means to test current flowing to the sounder under test conditions.
18. A consumer unit according to claim 16 wherein the sounder test means comprises a microphone to detect sound from the sounder.
19.A consumer unit according to any preceding claim wherein the emergency lighting unit comprises a control button configured to test the unit when the button is pressed.
20.A consumer unit according to any preceding claim wherein the emergency lighting unit comprises a control button configured to cancel an alarm when the control button is pressed.
21. A consumer unit substantially as described herein with reference to the figures.
22.A power supply system comprising a consumer unit according to any preceding claim and a lighting circuit for lighting local to the consumer unit connected to the same local circuit breaker as the emergency lighting unit.
23.A method for providing emergency lighting for an electrical consumer unit using a consumer unit as claimed in any one of claims 1 to 20 comprising the steps of: detecting loss of a power connection from a local circuit breaker within the consumer unit, and controlling a light source mounted on or adjacent to the consumer unit in response to the said detection.
24.A method according to claim 23 comprising the step of running a self-test process to test the operation of one or more of the emergency light source, the battery and an alarm sounder.
25.A method according to claim 23 or 24 wherein the local circuit breaker is connected to a lighting circuit local to the consumer unit.
26.A system for adapting a standard control unit to a consumer unit substantially as hereindescribed.