Light Alright Specification Description LIGHT ALRIGHT This invention relates to improving existing automatic emergency lighting systems that provide lighting in the event of a mains power failure. The effects of mains power failure can range from minor inconvenience to potentially life threatening situations. Sudden and unexpected darkness due to lights losing power can cause unwanted and unnecessary distress, exacerbated by age or disability. Locations where sudden darkness may cause distress and increase the risk of injury include showers, toilets and public spaces. Loss of domestic lighting during fire fighting activities should also warrant the installation of a reliable source of emergency light. There is a variety of dedicated high end automatic emergency lighting systems that require installation by qualified tradesmen. Cost, convenience and upgradability can be significant considerations when installing high end automatic lighting systems. Equally, there is a variety of low end automatic emergency lighting systems that do not require the services of qualified tradesmen to do the installation. These include units that plug into power outlets that activate when mains power fails, even if activation is not required. Significantly, emergency lighting that needs to be plugged into a power outlet may not be optimally placed and may be inadvertently switched off or unplugged. Logicality suggests that automatic emergency lighting should be located in the general proximity of existing lighting. There are systems conceived that do not require the services of a qualified tradesman, that can be plugged into existing light fittings, but all have shortcomings. Automatic emergency lighting that plugs into an existing light fitting at the expense of the light is an unsatisfactory solution. Equally, units that plug into existing light fittings that allow continued use of the existing light but require additional switching or switch activation combinations make them clumsy and difficult to configure, particularly for the less technically minded. Additionally, there appears to be little progress in the development of an automatic emergency light unit that can be plugged into an existing fluorescent light fitting that allows the continued use of the fluorescent light Another consideration is the length of time the battery backed automatic emergency lighting system can maintain useful light. The use of Light Emitting Diodes (LEDs) is common to improve longevity of useful light. Other methods used to improve battery life include timers to turn off the emergency lights at a preprogrammed time or additional switching on the emergency light units. Determining the correct time for an emergency light to stay activated is, at best, very difficult and introduces an unpredictable emergency lighting scenario. Additional switching to turn off emergency lights and then reset them, introduces a level of operational complexity that may cause confusion or failure in the event of an emergency. The shortcomings of existing automatic emergency lighting systems, as discussed, are overcome by the present invention. This invention describes automatic emergency lighting units that can be plugged into existing light fittings including but not restricted to incandescent, energy saving and fluorescent, that 1 allow continued operation of existing lights in said light fitting and activate in the event of a power failure under the control of the switch or switches for said light. Also this invention provides LED indication that mains power is present at the light fitting and the unit is functioning correctly. This invention utilizes a plurality of white LEDs with rechargeable battery backup. There are two forms of the invention. Figure 1 illustrates the format and appearance of the first form of the invention which can be used with a variety of lights that do not require the use of a starter. Figure 2 illustrates the format and appearance of the second form of the invention which can be used with a variety of fluorescent lights that require starters. Both forms of the invention resolve the shortcomings of existing automatic emergency lighting systems by supporting features which include low cost, directly pluggable into existing light fittings, retention of existing lights, no qualifications for installation, no tools required, emergency lights in optimum position, simple to upgrade or modify, fully automatic, fully solid state technology, controllable using existing light switch or switches, internal rechargeable battery automatically charges when the light is turned on, mains power 'present' indication. When installed and there is no mains power failure, the unit is totally transparent to the user. Figure 1 will be used to complement the operational description of the first form of the invention (emergency lighting unit) and is referred to subsequently. Upon removal of the existing light, which may be any type not requiring a starter, the emergency lighting unit is plugged into the light fitting from which the light was removed by inserting the plug section (10) of the emergency lighting unit into the light fitting. The light that was removed is now inserted into the socket section (13) of the emergency lighting unit. The electronic circuitry, rechargeable battery and LEDs are housed in the main body (11) of the emergency lighting unit. Light from the LED that indicates that mains power is applied can be observed through the translucent cover (12) of the emergency lighting unit when activation of the existing light switch or switches for said light occurs. Light from the white LEDs contained in the emergency lighting unit can be seen through the translucent cover (12) when there is a mains power fail and activation of the existing light switch or switches for said light occurs. The plug section (10) and socket section (13) of the emergency lighting unit can be, but are not restricted to, bayonet style fittings. Figure 2 will be used to complement the operational description of the second form of the invention (emergency lighting unit) and is referred to subsequently. Upon removal of the existing fluorescent tube and the starter, the starter plug (23) of the emergency lighting unit is inserted into the starter socket from which the starter was removed. The emergency lighting unit is then physically attached to the fluorescent light fitting and held in place with permanent magnets incorporated into the main body (21) of the emergency lighting unit. Alternatively, the emergency lighting unit can be supported using mounting holes in the bottom of the main body (21) of the emergency lighting unit or supported using the eye hook (24) on the end of the emergency lighting unit. The distance from the starter plug to the emergency lighting unit is determined by the connecting lead (22). The fluorescent light that was removed is now inserted into its original position. The electronic circuitry, rechargeable battery and LEDs are housed in the main body (21) of the emergency lighting unit. Light from the LED that indicates that mains power is applied can be observed through the translucent cover (20) of the emergency lighting unit when activation of the existing light switch or switches for said light occurs. Light from the white LEDs contained in the emergency lighting unit can be seen through the translucent cover (20) when there is a power fail and activation of the existing light switch or switches 2 for said light occurs. Figure 3 will be used to complement the electrical operational states of the invention (emergency lighting unit). The electrical operational states apply equally to the two forms of the invention. The emergency lighting unit has three modes of operation and will be described subsequently. In 'Mains Supplied' mode (30) the emergency lighting unit charges its internal battery, turns on the mains LED indicator, and ensures the emergency white LEDs are off. In this mode, the mains power is available and activation of the switch or switches has occurred. Also, existing light is on. In ' No Mains and switch off 'mode (31) the emergency lighting unit turns off the mains LED indicator and ensures the emergency white LEDs are off. Also, existing light is off. In 'No Mains and switch on' mode (32) the emergency lighting unit turns off the mains LED indicator and turns on the emergency white LEDs. Also, existing light is off. In all three modes (30), (31), (32) the emergency lighting unit monitors the mains voltage and impedance to determine the correct response regarding mains LED indication, battery charging and emergency white LED activation. Also, the diagram illustrates no electrical disruption to the connection between the mains supply and the existing light (33), thus maintaining unaffected operation of the existing light when the emergency lighting unit is installed and mains power is available. 3