Fynn's Help Page.
What is the difference between the many types of light bulbs (lamps)
Mains voltage
As their title suggests, these operate at normal mains voltages of 230-240. There are a whole range of lamp configurations such as linear halogen (long thin light bulbs), G9 capsules and the well known GLS filament light.
Low voltage
Low voltage light bulbs operate at low voltage power levels. The most common voltage is 12v (actually 11.9v) and the less common voltage is 24v. The light fitting requires a transformer to step down the voltage from the mains voltage of 230-240 volts. The light bulbs come in a variety of shapes, sizes and wattages and are sometimes referred to as halogen light bulbs. They create a crisp clean light, provide good colour rendering and can be easily controlled via dimming units. Despite operating at low voltages, they are not regarded as energy efficient or energy saving light bulbs.
Energy Efficient
The aim of an energy efficient light bulb is to create a good-to-high light output (lumens) using low levels of power consumption (wattage).
LED lights
An LED or light-emitting diode is a semi-conductor light source (the diode or diodes that emit light are set onto a miniature electronic circuit board). The main advantage is that the light emitted requires very little power so the wattage consumed is a fraction of a conventional light bulb. In addition, the LED generates very little heat and has an extended life quoted in excess of 50,000 hours. LEDs are supplied in either constant current or constant voltage formats and require a very specific wiring and power supply. Dimming LED light sources is not straight forward as they operate using very low loads, at very low voltages (6 volts ). Most conventional dimmers do not work effectively with them.
Fluorescent lights
Flourescent light bulbs or lamps provide a high light output whilst operating at low wattages and have a very long life. The lamps come in a variety of shapes generally described as ‘Tubes’ or Compact according to their shape. As fluorescents give out far less heat (because of their energy efficiency), they are ideal for use with lampshades made of delicate materials that can be damaged by heat.
Metal halide lights
These lights are generally used for specialist applications, such as retail spaces, where good colour rendering, high light output and long life is required. They are also often used to light exterior surfaces, large trees and gardens. As they have a high light output, quite low wattages can be used: often as low as 20 watts. However they require a ballast control and cannot be dimmed.
What should I look out for when buying a light fitting?
Table & floor lights
• Make sure the fitting is the right size for the space – look at its height, size of shade and importantly the size of the base.
• Watch out for in-line dimmers on your table lamps where you have 5amp sockets and conventional wall plate dimmers – you can’t dual dim on the same circuit.
• Consider your power socket positions so that trailing cables can be avoided or minimised.
Suspension / pendant lights
• Make sure the size of the fitting is appropriate to the space. Too small a fitting in a large space will lose impact. Too large a fitting and you might have glare/heat output issues.
• Consider the shape of the fitting and the influence this has on the light that is emitted. For example, a traditional chandelier with upright light bulbs emits light upwards but a traditional pendant with a shade emits light downwards.
• Consider the wattage of the light so that your dimmer units have sufficient capacity.
• Consider the weight of the light and ensure that there is a suitably strong fixing point available. You can purchase very good expansion plugs for plaster board ceilings that will provide a more secure fixing.
• Suspension lights/pendants that using fluorescent light fittings are NOT dimmable.
Wall lights
• Check where the power connection cable exits the wall light as this will influence the height of the fixed fitting.
• As well as considering the height and width, look at the depth of the fitting. For narrower spaces, such as staircases and hallways, you may need fittings that do not protrude too much.
• Wall lights with fluorescent lights bulbs are NOT dimmable.
Task & reading lights
• The ideal choices are low heat versions with either LED or fluorescent light bulbs. This avoids the risk of having a ‘heater on your desk’.
• Select models where the light source rotates and tilts to direct the light as required.
• Consider the size of the base of the product and make sure you have enough room on your desk to accommodate it.
Picture lights
There are two main fixing methods and each requires slightly different electrical cabling.
To the wall
The picture light is pre-positioned and fixed directly to the wall. A picture is then hung below this.
To the picture mounting
The picture light is fixed to the picture frame. In this case a power supply plate outlet called a ‘clock-point’ will need to have been installed to the wall behind the picture to allow for the power connection to the picture light.
What do I need to think about when positioning light fittings?
The position of these depends ultimately on the size and design of the fitting, the height and widths of the walls and the size and shape of the room. However, below are some general things to be aware of.
Wall light fittings
• Make sure the wall is clear of hidden cabling
• Check where the cable power supply point exits the light fitting. Is it at the bottom, middle or top?
• Check if the wall light requires a transformer that is not included within the fitting so that a practical place can be found to house this.
• General heights from the finished floor level are between 1700-1900mm – this ensures that the lights are above eye height, avoiding glare. However, it all depends on the design of the light.
• Always get a qualified electrician to install your light fittings.
Pendant light fittings
• Make sure you have enough cable “drop” supplied with the fitting. This is especially important if you have a very high ceiling height.
• Larger lights are generally best placed over fixed items of furniture like tables, desks and kitchen islands.
• Check that your fixing point can bear the weight of the fitting.
• Consider how you will change the light bulbs within the fitting.
• Consider the wattage of the light so that a dimmer unit of appropriate capacity can be used.
• Always get a qualified electrician to install your light fittings.
What are bathroom zones?
All bathroom lighting installations must comply to guidelines which are based on a zonal concept similar to that used for installation around swimming pools. Each zone rating (IP) is determined by the degree of risk of electric shock.
Zone 0
This is the area inside the bath or shower basin and is rated at IP68 and 12V.
Zone 1
Refers to the area above the bath or shower up to a height of 2.25 metres and carries a minimum rating of IP65 and preferably 12V.
Zone 2
Covers an area 0.6 metres wide immediately next to, and all around zone 1, plus the area over 2.5 metres high directly over the bath or shower. Wash basins should also be treated as zone 2. The minimum rating here is IP44. Where water jets are likely to be used for cleaning purposes in zones 1 and 2, the rating is a minimum IP65.
Zone 3
Has no special requirements, unless water jets are likely to be used for cleaning purposes. Equipment installed outside zones 0,1,2 and 3 must be suitable for the conditions most likely to prevail at that particular point.