Bulbs, Tubes and LEDs

Lighting can be a confusing subject. If you don’t know your fluorescent tubes from your LED lumen outputs then we’re here to help. Let’s go over the types of lighting on the market today.

Fluorescent Lighting

Fluorescent LightingMost offices, factories and commercial environments will typically have fluorescent tubes in some shape or form whether it is 6ft long tubes high in the ceiling, to rows of 2ft tubes within metal boxes / casings with bright polished reflectors to direct the light.

The technology is as follows; the lamps referred to as tubes illuminate an ultraviolet (UV) light when the mercury within the tube is energised by an electrical current. Initially the light will be white; however the effect of the chemical reaction coats the inside of the tube to create a yellow film, producing yellow tinged hue overtime.

Fluorescent tubes emit light around the entire tube, resulting in a lot of light wastage; reflectors are commonly used to direct the light shining up, down onto the desk or floor which helps combat the problem. There are so many variants of fluorescent tubes differing in length and diameter of tube to different types of control gear that run the fitting.

Fluorescent LightingHowever in simple terms if you have the largest diameter of tube that being tubes measuring 38mm diameter referred to as T12 tubes then your fluorescent lighting is of the oldest and least efficient variant. Unless the diameter of the tube is 15mm it is safe to say that conversion to Energy efficient LED lighting could yield savings of up to 70% in electricity usage. Good quality LED light fittings as designed and manufactured by Constant Lighting and paired with good control systems can yield good savings against T5 fluorescent tubes.

Another good benchmark test to gauge the efficiency of your fluorescent lighting is to look for a starter on the fitting if you can’t find this then you can check whether your lights are the earlier / oldest type of lights by switching them on. If the lights have a delay before providing illumination it would be good practice to engage a lighting specialist such as Constant Lighting to assess your current lighting and see if more energy efficient lighting would be beneficial. It probably goes without saying but to keep fluorescent tube lights working you need to re-lamp as required.

LED light fittings are virtually maintenance free.

Light Bulbs/Lamps

Light Bulbs/LampsThen you’ve got standard ‘light bulbs’. In the industry they’re called lamps, and if you want to be really specific they’re called incandescent lamps. These are the old-school, Thomas Edison invented, light bulbs in your home, desk lights and sometimes restrooms. The light is generated by an electrical current being passed through a reactive filament, which heats up and produces a glow.

Light BulbsAs time has progressed so has the use of CFL (compact fluorescent lamp) marketed as a more energy efficient lamp to incandescent lamps. However LED technology delivers a newer better alternative to both incandescent and CFL lamps.

When you do this correctly you can maximise the energy consumption from adopting an energy efficient light but also controlling its output delivering only light when its required and just the right amount.

High-intensity Discharge Lamps (HID lamps) / Sodium Vapour Lamps

High-intensity Discharge Lamps (HID lamps) Possibly one of the most commonly found lamps used in warehouses, factory and commercial premises.

These forms of lighting fixtures are now universally accepted as being very inefficient compared to quality LED light fittings. At Constant Lighting we find customers and potential customers disenchanted with these light systems over all others, sometimes with valid reason and sometimes purely because the wrong type of fitting has been used for the type of application.

It is common to see lighting schemes where HID Low Bay Fittings are used in a High Bay situation resulting in poor light levels and aged lighting installations where the lamps have been exchanged but replaced with a mixture of yellow and white lamps delivering poor colour uniformity and light levels. All of this can be corrected of course, however lights such as these are generally at great heights so access is usually problematic and you are still trying to fix a light that is highly inefficient compared with modern technology.

So is it all sales speak pushing LED technology over the existing systems? A common question raised by customers goes something as follows: “If I replace all the lights with new lamps, will I improve my light levels? As the specification on the lamp details 35,000 lumen output and 20,000 hours life expectancy.

High-intensity Discharge LampsThe answer from a sales point of view should always be answered firstly with why keep a fitting that consumes a over 400 watt when it could be replaced with a fitting that consumes less than half the amount. Taking the other points one by one the first being lumen output.

  1. The lumen output detailed as 35,0000 is the light output from the lamp not the light output when installed in the fitting. The reality is that the lamp is 360 degrees and almost half of the light emitted has to be channeled down to the floor immediately reducing light and efficiency. LED fittings well designed manage this problem much better.
  2. Life expectancy is often referred to as around the 20,000 hour mark. However HID lamps especially, suffer from substantial lumen depreciation over relatively short periods. This possibly explains why people often refer back to the lighting appearing brighter not so long ago. LED light fittings have much slower lumen depreciation meaning costly maintenance and lamp changeover isn’t required.

LED Lighting

LED LightingLEDs are the lights that everyone is talking about. The basics that probably everyone is now aware of is that LEDs are extremely energy efficient and in the case of comparing against incandescent lamps / bulbs consume up to 90% less power. With this efficiency comes reduced electrical costs.

Pair this with the money saved in maintenance and replacement lamps on conventional fittings, and LED light fittings become the default choice for those wanting to reduce electrical consumption. Therefore LEDs are very energy efficient, which most people are now becoming increasingly aware of. The monetary savings are easily demonstrated to clients, which at Constant Lighting we do daily.

Some detractors of LED lighting claim that LEDs are unreliable however good quality LEDs are very reliable. The old phrase you get what you pay for rings true with LEDs just like with other products.


LED LightingTop features of LEDS:

  • benefit from outstanding operational lifetime expectations.
  • resistant to external environmental factors from vibrations to impacts
  • perfect for outdoor applications as they are resistant to rain and wind
  • occupancy sensors and photocells allow for robust designs and flexibility in control
  • ‘instant on’ unlike traditional lighting which can take up-to 10 seconds to be ‘on’ fully
  • can be switched on/off regularly without an effect on the lifetime of the LEDs (unlike traditional lighting which degrades over increased switching)
  • increased efficiency when twinned with the correct control gear which Constant Lighting can advise on
  • fully operational at cold/low outdoor temperatures, ideal for freezer rooms vs fluorescent lamps that can be unreliable in low temperatures

Other benefits of LED lighting
may not be at the forefront of public knowledge, however we’ve highlighted some of the important advantages of LED lighting:

  • minimal infrared light emitted and very little UV emissions allows for LED usage where products and materials are sensitive to heat and UV lights such as food production and museums
  • endless design options and flexibility in application of light fittings
  • each LED can be controlled independently for colour, on/off and brightness
  • controllability and programmability allow for the resulting lighting to suit the mood and environment

LEDLEDs are ecologically friendly:

  • free of toxic chemicals vs conventional fluorescent tubes and bulbs
  • 100% recyclable
  • reduce lighting carbon footprint by at least a third
  • long lifespan reduces wastage and production as one LED bulb equates to 25 incandescent light bulbs

A big step towards a greener future!

At Constant Lighting we understand that lighting can be confusing and perhaps initially what you require is a general chat which may lead to a no obligation site survey. We are here to help and give you clear frank advice. We can guide you through the concepts of LED dimming delivering a managed plan for reduced electricity consumption through occupancy based strategies to scheduled peak demand reduction.

If we think LED lighting is appropriate we will advise accordingly, and likewise if we believe that retaining the existing lighting system is in your best interests we will tell you so.