Help Buying LED Strip
Buying LED strip can be very confusing and potentially very costly if wrong choices are made.The information below is intended to help you make the right decisions when buying LED strip and accessories.
Choosing the right LED strip
The type of LED strip you need really depends on what job you want it to do. The following questions will guide you in making the right decision:
1) Light Colour
LED strip is available in a wide range of colours and hues of white and can also be supplied as colour changing using a suitable controller. So this is the first decision to make:
- Do you want a fixed white light? If so do you want a warm, neutral or cool shade of white?
- Alternatively do you want light of a fixed colour? (E.g. Red, blue, green, orange, yellow etc)
- Finally do you want LED strip that can change colour? This can also include white if required.
Once you have chosen the colour of the light you can then move on to consider how bright you want it to be.
2) Colour Rendering
Colour rendering only applies to white light and is an index showing how well a light source reproduces the colour spectrum compared to natural light. The index starts at 1 for monochromatic light and goes up to 100 for natural daylight. This quality of light is indicated by the Colour Rendering Index (CRI) also sometimes shown as Ra.
For LED strip a CRI value of 80 is normally considered a good cost effective option for general lighting purposes. However, for more specialised lighting purposes where the light is close to natural daylight there is the option to select either CRI=90 or 95, however these do result in a higher cost.
LED strip is available in a very wide range of light outputs from 3W per metre up to 34W per metre. Brightness is clearly a key decision you need to make:
- For decorative purposes where the strip can be viewed directly low power strip between 3W/m to 6W/m should be used.
- For mood lighting where it is reflected off a wall or a ceiling then we need to consider medium power strip between 10W/m to 15W/m.
- For secondary lighting such as under cabinets or shelving then again medium power strip between 10W/m to 15W/m is normally sufficient.
- For brighter primary lighting where you may be replacing fluorescent lights or conventional lamps you need to use high power strip between 20W/m to 30W/m depending on lighting levels required.
Remember that to get the total power of your installation you have to multiply the number of Watts per metre by the length of strip being used.
As a rough guide, a metre of 3W or 4.8W LED strip could be used to replace a 40W incandescent lamp while a metre of 12W LED strip could be used to replace a 100W lamp.
4) LED Density
The density of the strip is the number of LEDs per metre. This is important because in some strip types it is related to brightness but more crucially it is related to how continuous the light is.
- 30 LED/m: Low density LED strip is not very effective as a light source because the LEDs are too spaced out. It is really only used by some suppliers to achieve a cheap price for LED strip.
- 60 LED/m: Medium density LED strip is a good general purpose solution giving a good compromise between cost and light continuity. However, a ‘spotty’ effect is visible if the strip is being put in a profile with diffuser and viewed directly but it is not so noticeable for reflected light.
- 120 LED/m: High density LED strip gives a much more continuous light and is suitable for most purposes except where the strip might be dimmed down. At low light levels a small ‘spotty’ effect will be noticeable.
- 240 LED/m: Very high density LED strip is the maximum available off the shelf. This strip gives the most continuous light possible with the LEDs almost touching each other for most LED types. However, the high density means that it is also the most expensive configuration.
As a general rule for situations where cost is an issue and the light will be indirect – such as under cabinet lighting or cove lighting – 60 LED/m will be a good option. However, for a more even light – particularly if the cove lighting is close to a ceiling or a wall – then 120 LED/m should be considered.
LED strip is available with various levels of protection depending on the location and environment of the installation.
- IP20 Non Waterproof: LED strip in its native form is not susceptible to damage from contact with reasonably large non-conductive objects it is not protected from water a vapour in anyway. If the strip is being installed in a dry environment then this option is the best one as it is also the least cost.
- IP65 Waterproof: There are various ways to provide basic water protection for LED strip, the most common being an epoxy resin or silicon costing. Epoxy is a low cost option and is fine for low power strips but will dry out and crack quite quickly for hotter running medium or high power strips. A better option for higher power strip is to use a silicone coating which is not affected by the high temperatures. However, both these options have the unfortunate optical effect of making the strip look cooler (whiter) than the non-waterproof equivalent. At Planet we have introduced a new nano-coating material which will provide waterproofing for LED strip but does not cause a colour shift.
- IP67/68 Submersible: Submersible strip is available and involves putting strip inside a hollow silicon tube and then filling it with silicon resin creating a completely sealed environment for the strip. This type of protection is really only suitable for low and medium power strips owing to the fact that the LEDs cannot dissipate the heat generated so effectively inside the sealed tube.
If you would like more help or technical advice in choosing the best LED strip for your project please call our sales line on 01600 800 100 and speak to Stephen or Rob – our resident experts.