FAQs & Glossary of Lighting Terms
Lamps
Lamps (also know as light bulbs) come in a large number of shapes & sizes. They are generally broken down into the following types:
Incandescent
Incandescent lamps are the original and most well known of all lamps. Commonly found in homes throughout the UK and Europe. Its operation depends on electricity heating up a small filament within a glass bulb. The quality of light is very good but it is extremely inefficient which has meant that the lamp is being phased out through the UK & Europe
Halogen
Halogen lamps take the concept of an incandescent lamp slightly further by introducing halogen gas in to the glass bulb. The efficiency is improved significantly over incandescent and it retains its fantastic quality of light
Halogen lamps are available in both mains-voltage (230-240V) and low voltage (12V & 24V). Recent developments in technology have led to more efficient varieties where reflector technology & special coatings have seen efficiency increase by up to a third
Good quality halogen lamps are available with life expectancies of up to 5,000 hours
Fluorescent
Fluorescent light sources offer a low energy solution to lighting. Although many believe the light to be cold and blue in colour, warmer varieties are readily available with colour temperatures similar to that of halogen and incandescent
Fluorescent lamps are available in many shapes and sizes and in some cases can be dimmed
Good quality fluorescent lamps can offer life expectancies of more than 20,000 hours so offer a very low maintenance option for lighting
Cold Cathode
Cold cathode lighting is very similar to fluorescent but the tubes are often custom made for each project to allow creative designs to be achieved. They can be coloured, shaped and curved to order
Some cold cathode lighting can be dimmed, although the range of dimming varies between manufacturers
Metal Halide
Metal halide lamps are commonly used in retail environments and for exterior lighting. The lamps are extremely energy efficient but are not generally dimmable. A warm up time of around 3-7 minutes is common
They are generally not suitable for use in residential installations and a great deal of thought should be given to their use. In particular, where lighting valuable objects or people, consideration should be given to the use of UV filters
LED
LED is the newest type of lamp technology. LED technology, as a serious light source, is still in its infancy but the recent explosion of electronic devices and vehicles using LED technology has meant there are exciting developments on almost a daily basis
LEDs are now available in dimmable varieties but often require special wiring or controls to achieve this. Recent retro-fit LED lamps have been launched by the main manufacturers including Philips & Osram. Some of these retro-fit varieties can be dimmed using regular household dimmers
Lamp life and performance varies massively between manufacturers. Whilst retro-fit varieties generally offer around 25,000 hours, some of the better purpose made LED light fittings claim lives in excess of 60,000 hours
Switching, Dimming & Control Systems
Switching
A light switch is a simple device that offers two options – light at 100% brightness (on) or light at 0% brightness (off)
Control is usually by a rocker switch, dolly switch or push button
Motion Sensors
Motion sensors such as PIR (Passive Infrared Red) sensors detect movement or people and animals. These are commonly used with outdoor security and orientation lighting as they work well in the dark and waterproof versions are common. Many feature daylight sensors to avoid triggering lighting during daylight hours and most have timers to allow an adjustable timer overrun setting
Models are available for mounting separately to light fittings so light fitting choice doesn’t need to be limited by the need for light fittings with integral sensors. Models are also available for recessing into interior ceilings and walls which is great for areas like cloakrooms & garages
Care should always be taken when choosing a motion sensor as these are not always compatible with energy saving lamps such as LED, fluorescent and metal halide
Dimming
A dimmer is a device which offers infinite options for a single circuit – light at 100% brightness, light at 0% and theoretically anything in between
Control is most commonly by a rotary knob or push button with one control per circuit so for example, a room with four circuits would require four control knobs or buttons
Modern push button dimmers are available with memory functions to remember a favourite setting and to softly bring the lights to the desired brightness when turned on (known as soft start)
Dimmers offer a great solution to increasing lamp life. Halogen & incandescent lamps in particular benefit from increased lamp lives. Dimming by 10%, which is hardly perceivable, doubles the lamp life. Soft start dimmers offer the added benefit of raising the light levels slowly which adds again to the lamp life
Scene and Mood Setting
A scene or mood setting device is designed to control more than one circuit simultaneously without the need for the user to set multiple dimmer switches each time the device is used. Most scene setting controls offer memory functions so that the user can designate settings for common settings – for example a dinner setting, TV setting, relaxation setting, work setting, etc. When a setting is recalled by simply pressing a button, all circuits will dim to the correct levels
Scene setting is great for spaces with more than one use or areas such as home cinemas. This allows the user to recall their favourite light settings at the touch of a button
Scene setting devices generally lead to more efficient use of the lighting reducing energy consumption and, as with dimmers, increase lamp life
Whole House Lighting Control Systems & Home Automation
Whole house control systems take scene setting one step further. They rely on a central processor & memory where settings for an entire house can be stored. The processors are configured to meet the client's individual requirements. In day-to-day use, such systems should be simple to use – a simple push of a button is all that’s required to set the mood lighting for a room or even a whole house
With systems such as the Mode Evolution and Lutron Homeworks, light fittings and scenes can be recalled in almost any room in the house. This allows automation to take place – for example when creating a ‘vacation mode’ to simulate occupancy when the house is vacant
Control systems can also be integrated with other controls and building services – from media systems such as Apple’s iPad & Crestron systems to burglar & fire alarms to trigger emergency routes during emergencies
These systems often offer possibilities of controlling electric blinds, curtains & shutters and many can even be interfaced with daylight sensors to dim lighting in rooms when natural daylight reaches a certain level – the possibilities are endless
Home automation systems, as with dimmers & scene setting devices, increase lamp life & help reduce energy consumption
Light fittings can be switched or dimmed. There are a number of options to do this: