Fluorescent tubes can be flexible

Replace fluorescent tubes with LED tubes

LED tubes up-to-date - We claim: 25 is the new 58!

Before the younger ones start out in horror: We are talking about the wattage of louvre lights and similar office lamps! Whereby the whole thing, if you look closely, is also a question of age. Because in the past, the number 58 played a much more important role in office lighting than it does today. Anyone who wanted to operate the popular louvre lights with lamellar reflector in the standard 150 cm size could rarely avoid purchasing two fluorescent tubes with a total output of 2 × 58 watts. That is a total of 116 watts for a single lamp. For a larger office, however, 3-4 or more such lights are often required. This creates a lot of electricity that unfortunately has to be paid for! Fortunately, thanks to LEDs, this is a whole lot cheaper these days. Namely with 2 × 25 watt LED tubes. Retrofit once - save more than half the electricity! How it works? We'll reveal the secret in TeuLexikon special to switch to LED tubes!


Do you already know what you want? Then just hit:

With LED tubes it no longer depends on the watt, but on how!

One would suspect spontaneously: 2 × 25 watts are much darker than 2 × 58 watts. 116 is more than twice as high as 50 and the lamp is therefore twice as bright as the supposedly weaker one. Unfortunately, this assumption is based on a mistake in reasoning. Because the big revolution of the LED tubes is that they use their wattage much more efficiently than other light sources. This is the only way to achieve the minimum wattages of some incandescent lamp replacements. With 5W an incandescent lamp doesn't get very far, an LED lamp, on the other hand, can produce a pretty decent light with it. So there is no getting around it: The watt alone is no longer sufficient as a benchmark! You can recognize the brightness of LED tubes from other data. Of course, the following also applies here: No rule of thumb, no matter how precise, can replace the practical test. But there is one thing she can do: Give orientation in a technology branch that is becoming noticeably more confusing!

Do not underestimate the beam angle with LED tubes

The energy-saving operation of the LED tubes can also be explained without any abstract values ​​such as lumens, candela or lux. At least in broad terms. Imagine a switched on fluorescent tube. It shines nice and bright, in a more or less crisp white and - on all sides! As a rule, fluorescent tubes have a radiation angle of 360 °. What sounds pretty comprehensive and flexible at first, can cause a lot of light to evaporate unused during operation. Because office lights usually have a beam angle of approx. 120 °. That means: only one third of the gigantic light aura of a fluorescent tube comes out of the lamp. The remaining two thirds cannot be used for office lighting. Reflective back plates are also of limited help.

Advantage of LED tubes: it sticks in them LED strips, which emits the light in a significantly smaller angle (usually between 120 and 160 °) to the environment. So it is perfect for office luminaires that are already aimed at such light cones. You just have to make sure that the LED tube is the right way around (with the strip facing up) and you can start saving!

Is lumen the new watt?

Of course, the triumph of LED tubes is not due to the beam angle alone. The differences in light generation between fluorescent and LED are even more central. To put it simply: In fluorescent tubes, a mixture of noble gases is ionized and transmitted to the environment as light. A very energy-intensive process that generates a lot of unused heat.

LEDs don't have this problem. The keyword is Electroluminescence. The LED body gives when an electrical voltage is applied electromagnetic radiation to the environment that we perceive as light. THAT is modern lighting: efficient, environmentally friendly, cheap!

As LED tubes need fewer watts, this size is no longer sufficient for comparing brightness, as I said. It works better with a look at the light output, or: Lumens per watt! The lumen is the undirected luminous flux that is emitted by a light source. The higher the light output, the higher the proportion of the luminous flux that can actually be perceived by the human eye. A 58 watt fluorescent tube has approx. 5000 lumens, which corresponds to a light output of approx. 86lm / W. 150cm LED tubes with 25 watts of power usually have a luminous flux of 2700lm. These are incredible 108 lumens per watt! And that at less than 50% of the wattage compared to the fluorescent tube!

Only 120cm? Shorter lights can also be helped.

For the basic calculation we have so far assumed 150cm long fluorescent tubes or LED tubes. Of course, these don't fit into every louvre luminaire. But the practical LED effect Of course, it also works with shorter tubes. A 150cm long louvre luminaire would significantly overload some small rooms. 120cm are usually enough. Instead of 2x58W, you often have to deal with 2x36W. Just a size smaller. And then of course there are the particularly popular square louvre lights. You can still find them today in many OWA ceilings and similar ceiling systems. If you are looking for suitable fluorescent tubes, you can use the 4x18Watt combo. And hey presto, with this optically compact lighting solution, you have already reached 72 watts of total wattage. It doesn't have to be. The right replacement LED tubes for common tube sizes at a glance:

Fluorescent tubesLED tubes
2 × 58 watts (150cm)2 × 25 watts
2 × 36 watts (120cm)2 × 18 watts
4 × 18 watts (60cm)4 × 10 watts

Tip: Conversion to LED tubes for CCG and VVG is particularly easy!

If you have found the right LED tubes with the help of the table above, they can already be inserted into the existing louvre light. However, you should first determine exactly which ballast technology your previous lighting is working with. But we can reassure you: The selection is not too large and most of the variants are LED retrofitting is not difficult. Easiest to remember: If you operate your louvre luminaire with an electronic ballast, the luminaire must be from Qualified personnel with electrotechnical qualifications to be rewired! With most KVG / VVG circuits, it is sufficient to replace the starter of the fluorescent tube with a dummy starter. The variants at a glance:

BallastcircuitRewiringBlind starters
VVG or KVGSingle or duo switchingNoYes
VVG or KVGTandem connectionYesYes

With new lights it’s also possible without a starter

Our tips and advice on Conversion from 2x58W fluorescent to 2x25W LED tubes also help you with Complete switch on LED. In other words, if simply replacing tubes is not enough for you and instead you want to use new louvre lights that are tailored to the revolutionary technology from the outset. The advantage: You do not need to be retrofitted and you will usually not need any starters included with the tubes. Simply screw in the LED tubes and benefit immediately from fresh LED light!

We summarize:

  • With LED tubes, watt is no longer sufficient for comparing brightness!
  • Lumen reveals more!
  • The higher the light output, the brighter LED tubes can appear!

Excellent: This text is one of the Top 10 in blog and TeuLexikon!
Which still? Find out here:

►►LED light panel - The top 10 in blog and TeuLexikon! ◄◄

►► Also new in the blog:Top 6 - the best LED ceiling panels in the shop! ◄◄