Tag Archives: LED

Tero Explains: What is EPREL for light sources? 2/3

The first article of this 3-part blog post series was dealing with the near-term history of European directives and regulations related to energy efficiency and different energy-related products (ErP), not only energy-using products (EuP).

Starting from Kioto 2005, this process has then proceeded to the situation, where new kinds of regulations have been taken into use, concerning many energy-related products, the latest of those being light sources.

Since 1st September 2021, the insertion of light sources into the EPREL (European Product Registry for Energy Labelling) database has been possible officially. Some problems have occurred in the technical insertion process and also in decisions over which component is a light source and which component is not. The term ’light source’ is defined in the European Commission Regulation EU 2019/2020 laying down ecodesign requirements for light sources and separate control gears (Single Lighting Regulation, SLR).

In this blog post, you can learn how light sources are categorized and what this categorization means in each case.

Categorizing the light sources – is the light source removable or not?

I shortly presented the terms of ’containing product’, ’light source’, and ’separate control gear’ in my earlier blog post in this series. SLR requires that the light source and separate control gear are removable so that the luminaire/fixture can be called the containing product. If not removable, the whole fixture itself has to be regarded as a light source.

Here starts the categorization. I concentrate on light sources in this post. The easiest case is a containing product without a light source: Not Applicable (it is just an empty luminaire body that has no light source included). The second easiest case is the LED lamp that you can buy from a retail store. Then it is not containing a product but only a light source. The sales package in store should include an energy label and other information defined in SLR regulation. Additionally, the lamp information should be added to the EPREL database.

Then let’s proceed into the case(s) where containing product includes the light source.

The first question is that is the light source itself removable? If it is, then it has to fulfill light source requirements defined in Ecodesign/SLR regulation. It is enough that the light source is removable from the containing product without breaking the light source. The containing product is allowed to still deteriorate in that case, but not the light source.

Then there is the next case. If the light source is NOT removable without breaking it, then the whole lighting fixture is considered a light source. The sales package of the containing product has to include an energy label and also other information defined in SLR regulation.

So, the key point is the question, is the light source removable or not? The question, is the light source replaceable or not, is not relevant otherwise than for the end-user that is you or me, a consumer. The supplier (or manufacturer) has to inform in their technical representation, why the light source is not replaceable. This technical documentation should also include information that “this containing product includes a light source the energy efficiency class of which is X”. X can vary from A to G in the new energy efficiency classification. Light source information together with the energy efficiency class must be found in the EPREL database.

Requirements defined in SLR/Ecodesign Regulation

There are several requirements defined in SLR/Ecodesign regulation. These are:

  1. Energy efficiency requirements
  2. Functional requirements
  3. Information requirements (markings)

Energy efficiency requirements

First of all, energy efficiency requirements demand that power consumption of a light source can’t exceed Pon,max (W), which is defined for different light sources in the 2019/2020 SLR regulation. Pon,max depends on many parameters, some of them are real and measurable values and part of them are computational values or factors/multipliers. Computational values are based somewhat ”loosely” on the real world.

If you measure for example your LED board/module in the integrating sphere, and the light source is defined as a non-directional light source (NDLS), you can use all lumens that you measure in your sphere as useful luminous flux (term defined in SLR regulation). If you have a directional light source (DLS), the regulation defines which portion of light you can use for this directional light source. Usually, the measurement for the DLS light sources is better to carry out with a goniometer that can measure light intensity at different angles unlike with integrating sphere which collects all the light rays and integrates them for the spectrometer through an optical fiber.

This relates essentially to EPREL energy class information because you define the energy class according to the following equation:

hTM = (Fuse/Pon) x FTM

where hTM is total mains efficacy, Fuse and Pon are LED parameters (useful luminous flux and power consumption of the measured LED board, COB LED, or any other light source) that are measured from the light source and FTM is a multiplier that is 1.00 for mains light source (MLS, e.g. AC LED) and 0.926 for the non-mains light source (NMLS, e.g. LED board that needs a separate control gear for operation).

The updated measurement software can calculate hTM value directly when you first choose in the software, is your light source NDLS or DLS, and is it NMLS or MLS light source. So spectrometer first measures luminous flux and power consumption and calculates LED luminous efficacy, and then by using a correct multiplier for your light source, calculates total mains efficacy that defines the energy class. For example, in the case of an LED board with separate control gear, this multiplier is 0.926 (see the previous paragraph). Then you can add your LED light source to the EPREL database by filling in all public information, and the EPREL database creates the final energy label for your light source. For market surveillance, you have to add also other technical information, that is not publicly available for everyone.

Functional requirements

Then there are functional requirements. They include many parameters that also depend on the used control gear (LED driver in our case).

  • CRI index ≥80 (outdoor and industrial applications are the exceptions)
  • Power factor cosf (certain limits, depending on the control gear used)
  • Lumen maintenance factor (LED and OLED light sources) àbased on L70B50 value in hours
  • Survival factor (LED and OLED light sources) àrelated to the lumen maintenance factor
  • Color consistency (LED and OLED) àhas to be MacAdam 6-step or lower
  • Flicker PstLM (LED and OLED), depends on the control gear à PstLM≤1.0
  • Stroboscopic effect (LED and OLED), depending on the control gear à SVM value≤0.4

Two last values are defined at full load condition.

Information requirements (markings)

Finally, there are information (marking) requirements.

The surface of the light source itself (not package marking):

  • Useful luminous flux (lm)
  • CCT/Correlated color temperature (K)
  • For directional light sources (DLS), also radiation angle (°)
  • Depending on the size of the light source, the priority is 1) Luminous flux, 2) CCT and 3) radiation angle.

Packing information:

For all light sources, which are sold separately in an independent packaging (but not in a containing product) through a point-of-sale, there are several requirements regarding the packing information. Some of these are mentioned below. It is to be noted that the three first ones shall also be marked on the surface of the light source, given that there is space for all three.

  • Useful luminous flux (lm)
  • CCT/Correlated color temperature (K)
  • For directional light sources (DLS), radiation angle (°)
  • Electrical interface details
  • L70B50 lifetime (hours)
  • On-mode power (Pon)
  • Standby power (Psb)
  • Networked standby power (Pnet)
  • CRI/Colour rendering index
  • Indication if CRI<80 (note; the application must allow it)
  • Indication if the light source is designed for non-standard conditions
  • Warning sign, if dimming is not allowed or can be realized only with specific dimmers
  • Warning sign, if the light source contains mercury

As an alternative to text, the information can also be given in the form of graphs, drawings, or symbols. Besides this information, the packing must show the energy label.

If a light source is being sold as a part of containing the product (and the light source is removable), the requirements are different. In this case, there can’t be any energy label on the containing product packaging. The packaging must indicate the following:

  • Information on whether the light source is replaceable or not, must be shown on the packaging (in the case of end-user sales) or on a free-access website
  • Information if the light source can be replaced only by a professional

As an alternative to text, the information can also be given in the form of graphs, drawings, or symbols.

Conclusion

This is what SLR is in a nutshell. And how you define energy class for your light sources. For printing the label from the EPREL database, you can ask help from the EPREL help desk or your local officials.

In the third, and the last, article of this blog post series, we concentrate on the effects that these regulations may set for the whole lighting industry. As you can see, many parameters depend also on the driver/control gear that is used with the light source. How this affects the component (light source and/or control gear) selections to make genuinely Eco-designed containing products, this we will discuss in the last part of this series.

If you have any questions, you can email me at tero.nurmi@light.fi.


Tero Explains: The New EU Regulations coming on September 1/3

In this blog post series of 3 articles, our technical sales Tero Nurmi will tell you about the new EU regulations which will take part on 1st September 2021. In this blog series first Tero will tell you, what are these two different regulations: Single Lighting Regulation (SLR) and Energy Label Regulation (ELR). After that, Tero will go deeper into the subject of how this really affects the lighting industry.

What is ErP? 

ErP is the abbreviation of Energy-related Products. It also refers to Energy-related Products Directive (ErP) 2009/125/EC that replaced the old Energy-using Products Directive (EuP) in November 2009. The original EuP was taken into use in 2005 to fulfill the Kioto agreement requirements for reducing carbon dioxide emissions.

The ErP broadened the range of products that were covered in EuP. Earlier only directly energy-consuming (or using) products were covered. Now ErP directive also covers the products related to energy. This could be for example water-saving taps, etc.

The idea is to cover the whole product supply chain: design stage, production, transport, packaging, storage, etc.

Products that comply with this new ErP directive are recognized from CE -marking. In this case, the CE -mark covers product safety and energy efficiency requirements. 

How this relates to lighting? 

If we take the new directive, ErP EU 2019/2020, we can divide it into two groups concerning ecological design requirements:

  • Light Sources 
  • Separate Control Gears 

These requirements can also be applied to luminaires. The luminaires are so-called containing products that contain a light source(s) and control gear within the luminaire.

The development has gone further: now these ”ecodesign” principles are applied to the smallest possible units that can be considered as light sources. In this text, we do not go too much into details. I’ll explain everything more precisely in the further blog posts.

In December 2019, the European Commission published two different regulations: Single Lighting Regulation (SLR) and Energy Label Regulation (ELR). The former is also called Ecodesign Regulation for Lighting. SLR defines performance requirements, which are product-specific, for energy-using and energy-related products, while ELR includes labeling requirements for selling the products in the EU market.

There is a general state of mind that both these regulations, SLR and ELR, will apply from 1st September 2021.

SLR and ELR, and especially their application to LED light sources, will be handled more elaborately in forthcoming posts. 

Dim-to-Warm – COB LED that dims like halogen

Dim-to-warm

Dim-to-Warm is COB LED which works like halogen lamp when dimmed. Its specialty is that when you dim it the color temperature gets warmer. Usually dimming does not affect the color temperature of the LED. Dim-to-Warm LED imitates the effect of the halogen lamp which gets warmer by dimming. With full power you can get color temperature 3100K and at lowest 1850K.

Dim-to-Warm LED suits especially highly for decorative luminaries, for example used in restaurants, hotels, cruise cabins and home interiors. It’s perfect for space where you want to have dimmed and warm toned atmospheric lighting.

LED has great advantage compared to an incandescent lamp. Its power consumption is less than 10% of the incandescent lamp’s power consumption.

The color temperature of candlelight, incandescent and halogen lamp.

The color temperature of candlelight, incandescent and halogen lamp.

 

There are seven different packages from 900 to 3000 lumens. You can download more information about the product here.

Where and how to use?

Dim-to-Warm LED is great for places where you want the light that dims like halogen or incandescent lamp. You can use it for example for restaurants, hotels, cruise cabins and decorative luminaires where you have been using halogens before.

It’s easy to use. You can use Dim-to-Warm LED for all the luminaires where you have been using COB LED or you can use it to replace led modules. All optics, lenses and reflectors that are compatible with COB LED, suit also for Dim-to-Warm LED. LES area is CLC20-series for 9,8 mm and at CLC30-series for 15,2 mm.

How Dim-to-Warm works?

As we know, usually LEDs don’t change the color when you dim them. They always retain approximately the same color temperature when the brightness is reduced. LED’s brightness depends on the current; reducing the current the brightness reduces.

Dim-to-Warm LED is made from cold and warm LED areas. It has an internal control circuit which dims the cooler area first and later starts to control current of the warm one.  The color temperature gets warmer when dimmed.  This way the dimming works similarly in incandescent or halogen lamp.

The diagram below shows how the color temperature gets warmer when led is dimmed down and the current and brightness reduces (black color). You can also compare it to halogen lamp (grey color).

 

Dim-to-Warm is a COB LED, so you don’t need any complicated special features from the driver, like two-channeling or programming features. Ordinary triac dimmable driver is enough. We have tested ELT’s DLC-drivers with it, and they have good compatibility.

Click the button below to download the datasheets and material. You can find more information and our product codes from the presentation. If you have any questions about Dim-to-Warm, please don’t hesitate to contact us.

Download Here

Why Heat Pipe is Better than Traditional Heat Sink?

You will need a heat sink when you use a COB LED in your luminaire. The traditional way of transferring the heat away from the light source is to use a passive aluminum heat sink. In this blog post, I’ll introduce you the new way of cooling: heat pipe.

Traditional heat sinks are based on the fact that aluminum transfers heat away from the light source. The higher the power of the LED is, the more you need aluminum.

This grows the luminaire’s size and makes it more expensive. The bigger size of the luminaire makes logistics costs go up and increases the price for end user even more.

We have a better solution for cooling high power LEDs without the need for noisy fans or heavy heat sinks.

Furukawa Heat Pipe (HYC Series)

Heat pipe technology is traditionally being used in computers and for example in satellites. But now it is available in lighting.

Furukawa HYC Series uses heat pipe technology to transfer the heat and makes heat sinks more efficient in cooling the LED.

how heat pipe works

Its thermal conductivity is almost 200 times better compared to copper. This also allows the heat sink to be a lot smaller than we are used to.

Smaller heat sink reduces the weight of the luminaire dramatically. This reduces transportation costs as well as the amount of other materials needed.

The Heat Pipe effectively transfers heat from the heat source and as a result makes the cooling faster than ever.

Unlike many Chinese manufacturers, Furukawa uses oxygen-free copper in its Heat Pipes, which means that their lifetime is over 20 years.

Heat Pipe vs. No Heat Pipe

Cooling with and without the Heat pipe

Save Money and Environment with our aLED Light Engine

aLED Engine

aLED Light Engine (Furukawa Heat Pipe + Citizen COB + optics + aLED Driver)

As a great example, I want to introduce you our own aLED Light engine that uses Furukawa heat pipe with Citizen COB. aLED Light Engine produces over 40 000 lm and weights only 1kg (without driver and optics). And only 3.6kg with optics and driver.

By combining Citizen COB and heat pipe technology, you can build luminaires that:

  • Produce a lot of light
  • Are light in weight and small in size
  • Save environment
  • Are completely recyclable

Furukawa Heat Pipes are compatible with Citizen CLU04x and CLU05x COB LEDs.

Download an example of different combinations and datasheets for custom models with screw holes for Citizen COBs.

Download Here

Why Should You Choose the New aLED Module

We redesigned our aLED-modules based on customer and market feedback. Here is  a brief explanation on what is different compared to previous version. And why I think you should consider using aLED modules.

 

Figure 1. New aLED Modules with examples of different connector locations.

Better efficacy (159-191 lm/W)

We upgraded the SMD LEDs used in the modules to better suit our customers’ needs. aLED modules now have efficacy from 159 lm/W to 190 lm/W. Efficacy depends on the color temperature and you can see the efficacy by CCT here:

  • 2700K (174 lm/W)
  • 3000K (177 lm/W)
  • 4000K (185 lm/W)
  • 5000K (191 lm/W)

Better placement of LEDs

We have changed the design of our aLED module. LEDs are now placed on the center line of the module so the installation of optics is easier.

aLED modules dimensions have also changed. New modules are now either 279.2 mm or 558.4 mm in length and 20 mm or 40 mm in width. 

Different options for connectors

It is now possible to order aLED modules with connectors either on the frontside or on the backside. Traditionally the connectors have been on the frontside, but these new backside connectors allow you to hide the wires behind the module and inside the profile.

For longer luminaires, there is a possibility to use backline, so you won’t need long wires. Short wires to connect multiple modules together will be enough (figure 2).

Figure 2. a) How to connect modules without back line option. b) How to utilize the back line option of the aLED modules.

Long lifetime

Thanks to the upgraded LED, the lifetime of aLED modules has also increased. You can see the lifetime prediction below. But to be brief: at maximum TC temperature (85°C) the lifetime (L70B50) is over 100.000 hours (figure 3).

Fikure 3. The lifetime of aLED Module (L70B50)

Friendly to environment

On top of high efficacy and the possibility to save energy, aLED modules are also recyclable. You can recycle all parts of module, even the PCB.

In addition to all these changes aLED modules prices have also dropped to more competitive level.

You can find the technical details of 4000K modules from the table below. You can download the datasheets of these new modules by clicking here.

Product Code Color Temperature (CCT) Color Rendering (Ra) Luminous Flux (lm) Forward Current (mA) Voltage (V) Power (W) Efficacy (lm/W) Length (mm) Width (mm)
CALOSNU0405 4000 80 1182 600 11.6 7.0 170 279.2 20
CALOSNU0410 4000 80 1224 600 11.0 6.6 185 279.2 20
CALOLNU0805 4000 80 2363 600 23.2 13.9 170 558.4 20
CALOLNU0810 4000 80 2448 600 22.1 13.3 185 558.4 20
CALOLHU1610 4000 80 4895 600 44.1 26.5 185 558.4 40
CALOSND0405 4000 80 1182 600 11.6 7.0 170 279.2 20
CALOSND0410 4000 80 1224 600 11.0 6.6 185 279.2 20
CALOLND0805 4000 80 2363 600 23.2 13.9 170 558.4 20
CALOLND0810 4000 80 2448 600 22.1 13.3 185 558.4 20
CALOLHD1610 4000 80 4895 600 44.1 26.5 185 558.4 40

 

Download Datasheets

 

In addition to these new models, all our previous module models are also still available.

How to Connect LED Modules into AC Network

In my earlier post I went through the procedure of how to physically connect a single LED component into an AC network. The connection was made between COB LED and the LED driver. When connecting LED modules (LED diodes assembled on the PCB board) you do it pretty much the same way with slight differences.

Connecting an SMD LED module into the AC network

As with a COB LED component, you will need a suitable driver for your module (see: how to choose a constant current LED driver).  You connect the positive terminals and the negative terminals of the LED driver and the LED module together to create a closed electrical circuit.

The difference to connecting a single LED component is that you may have to connect several LED modules into the same LED driver. In such case, you have to use series connection. This means that you still have to create a closed electrical circuit formed by the LED driver and these LED modules on the secondary side. You arrange the primary side like you would with single LED components. On the secondary size you connect the positive terminal of the first LED module (leftmost module in Figure 1) into the positive terminal of the LED driver. Then you connect the negative terminal of the last module (rightmost module in Figure 1) to the negative terminal of the LED driver. See Figure 1 below that shows all connections between the components.

Figure 1. Connection of LED modules into AC network through the driver.

How do you make other connections? Series connection means that you always connect the negative terminal of the previous array to the positive terminal of the following array in the chain. See again Figure 1. The output voltage of your LED driver defines how many LED modules you can drive with one driver. In case of Figure 1, one LED driver drives three LED modules. If voltage over LED module is for example 12V, the output voltage of the LED driver should exceed 36V. In the real world, you have to take into account tolerances. So in this case, 40V can be used as target for the driver maximum output voltage.

In the same way, you can connect multiple COB LEDs in series. This may be the case when you need vast amount of light.

How to actually do it?

As for physical connections of SMD LED modules, there are four options:

  1. PCB terminal block connectors
  2. Soldering
  3. Wire-to-board connectors
  4. Board-to-board connectors

PCB terminal block connectors are quite popular. They are soldered on the PCB board in the reflow process (in reflow oven) after the assembly process. You push the wires into those PCB terminal blocks in the same way as you would push the wires into the push-in terminals of solderless connectors in the single COB case.

Figure 2. PCB terminal block connector (2-pole)

Soldering is an option, if there are separate soldering pads reserved on the PCB to solder the wire(s) with tin. Soldering is usually a more cost effective option.

The numbers 3 and 4 are the special cases when you wish to interconnect two modules with each other. I’ll skip them for now and save them for later post.

If you’re interested in aLED’s new, improved LED modules, read more over here.

Feel free to drop a comment if you have questions on this topic.

How to Connect a Single LED Component into AC Network

I have two blog posts for you focused on how you connect COB LED components into the electrical network. I mean, when you have either a single COB LED or an LED module based on SMD LED components assembled on a PCB board.

Compared to traditional lighting, connecting LEDs to the electrical network is a whole new world. LEDs need direct current (DC) to light them, alternating current (AC) will not work. There are also AC modules available but those are not covered here.

In this post I will concentrate on connecting single COB LEDs. In case you are interested in connecting LED modules, I will write about that in my next post.

LED driver

You will need an LED driver, which is actually an AC/DC converter. It converts the AC voltage/current of the electrical network into the suitable DC voltage/current needed by the LED component. You will find the requirements of the LED from a datasheet provided by the manufacturer. If you need help in choosing a driver, you can read our guide.

Figure 1. Example of an AC/DC converter, LED driver. This one is from ELT with dipswitches, which means that you can choose the driving current.

Connecting COB LED into the AC network

In case of COB, you will have to create a closed electrical circuit so that the electrical current can flow through the LED component. A COB LED is basically a diode in its electrical nature: the current can flow only in a forward mode. This means that you must connect the positive (+) solder pad of the COB LED into the positive terminal of the LED driver. In the same way, you connect the negative (-) solder pad of the COB LED into the negative terminal of the LED driver. See the Figure 2 below.

 

This way, you create the closed electrical circuit that is needed to feed current through the LED so that it gives light. This closed electrical circuit formed by the LED driver and the COB LED is called the secondary side of the LED driver. LED driver feeds the power and current into the closed electrical circuit, and thus through COB LED, on the secondary side.

 

Figure 2. COB-AC Network

 

On the primary side, the LED driver gets electrical power from electrical network, AC network. The terminals of the LED driver on the primary side are called line and neutral. They are connected into the line and neutral connections of the AC network. If you have an LED driver with cables, they are usually blue (neutral) and brown (line). Some drivers also have a ground terminal, which is usually connected to the luminaire body with grounding wire. However, the closed electrical circuit is needed also on the primary side; between the network and the driver.

Usually, you will need to use some kind of terminal block to connect the driver into the electrical network on the primary side.

Picture of a terminal block

Figure 3. The example of terminal block to connect the LED driver into the electrical network.

Two options

Finally, as for physically connecting a COB LED into the LED driver, you have two ways to do it:

  1. solder the wires on the solder pads of the COB
  2. use solderless connectors.

In the first method, you manually solder the wire by using soldering iron with high temperature that melts the soldering material such as tin. After cooling, there is a joint between the wire and the COB solder pad. You need two wires, one for plus and one for minus solder pad.

In the second method, you use a solderless connector.

Figure 4. The solderless connector.

The solderless connector does the same effect as the soldered wire. You need the electrical connection also in this method, but you won’t need to solder the wire by melting tin. You just push the wire into the push-in terminals of the connector. Again, positive to positive and negative to negative terminal. They are marked on the connector. Basically these push-in terminals work with a combination of metal plates and springs that then make the connection to the solder pad of the COB LED.

The difference between these methods is, that unlike with soldered joints, in the solderless connector method the springs may loosen a bit over time and loss of contact may occur. Solderless connectors are generally thought to be more expensive than manual soldering.  

In my next post I will go through the steps for connecting LED modules.

What We Are Presenting in Elfack?

Elfack exhibition will be held in Gothenburg, Sweden from 9th to 12th of May. As it has been with previous exhibitions, we will be releasing new products and presenting the latest technology at our stand.

This year we will introduce and present the following products at our stand F04:70.

aLED Engine

aLED Engine

aLED Light Engine

We designed aLED Engine for applications that require a lot of light. aLED Engine consists of Furukawa heat pipe and Citizen COB LED.

In addition you can also choose a suitable optics and LED driver for the light engine from our selection. Suitable drivers are available as on/off, 1-10V dimming and DALI dimming.

aLED Engine is also compatible with Merrytek sensors, which allow you to control the lighting as you wish.

The 300W engine produces 36.000 lm at 4.000K and weighs only 3,6 kg with a driver installed.

aLED Engine will be at our stand in Elfack. There you can see the engine in action and try it with a daylight sensor.

Download More Information

Furukawa HYC Series

Furukawa HYC Series uses heat pipe technology to transfer the heat and makes heat sinks more efficient in cooling the LED.

how heat pipe works

How Heat Pipe Works

Heat Pipe’s thermal conductivity is almost 200 times better compared to copper. This allows the heat sink to be a lot smaller than we are used to.

Smaller heat sink reduces the weight of the luminaire dramatically.

The heat pipes effectively transfer heat from the heat source throughout the whole heat sink cooling the heat source faster than ever.

Heat Pipe vs. No Heat Pipe

Heat Pipe vs. No Heat Pipe

Furukawa heat pipes are compatible with Citizen COBs.

Furukawa heat pipes will be at our stand so you can see and try how light they are.

Read more about Furukawa heatpipe from here.

aLED & Letaron Drivers

aLED Driver

aLED Driver

aLED and Letaron offer a versatile range of both constant current and constant voltage drivers from low to high power (from 1 W up to 600 W).

Ouw own aLED drivers are best suited for high power applications. They are all available in IP68 and can be ordered as on/off, 1-10V dimming or DALI dimming.

Letaron drivers are best suited for low power applications, although they are available up to 52W.

Letaron offers a variety of designs to suit your needs including round, rectangular and slim models.

The Letaron low power drivers are also compatible with OLED light sources.

aLED and Letaron drivers will be on at our stand so you can see and try them yourself.

Merrytek

Merrytek sensors

Merrytek offers a wide range of different sensors. Some sensors come with LED driver and some are independent and can be connected to LED driver.

Merreytek has products particularly designed for eg. homes, schools, stairways, warehouses, offices, parking garages and outdoor use.

Merrytek’s intelligent lighting control products include:

  • Microwave motion and daylight sensors
  • Dimmable LED drivers
  • LED drivers with intergrated sensors

There will be Merrytek products on display at our stand. We will have an aLED engine wiht Merrytek’s daylight sensor on our stand, so you can see how it functions.

Citizen Gen 6, AC COB &Vivid Series

Citizen released Gen 6 COB and AC COB earlier this year with improvements compared to the previous versions.

Thermal Resistance

Thanks to better heat resistance, you can use much smaller heat sink. Gen 4 on the left, Gen 5 on the middle and Gen 6 on the right.

For the new Vivid series we’ve prepared a demo wall at Elfack for you to examine the possibilities of color quality control in LED lighting.

Seminar about color quality

We will organize a seminar about color quality on the first day of the exhibition.

Color comparison Vivid COBColor Comparison Regular COB 3000K Ra80 vs. Vivid Brilliant

The seminar will take place on Tuesday 9th of May.
Time: 16:00-19:00
Place: Hotel Gothia Towers, Tower 1, meeting room R22-23

The program:

  • Doors open at 16:00
  • Coffee
  • Welcome / Arrant Light Oy by Janne Mäkinen, Managing Director / Arrant-Light Oy
  • Color Quality with CITIZEN by Kosuke Tsuchiya, Field Application Engineer / Citizen Electronics Co.
  • Demonstration and open discussion
  • Refreshments and snacks
  • Close at 19:00

Please sign up for the seminar as soon as possible or latest by April 30th. We have limited seats and there is room for the first 20 persons only.

Sign Up for Our Seminar

Welcome to visit our stand F04.70 at Elfack.

All datasheets and other material will be available from our website soon. If you wish to download material about these new products before the exhibition. You can do that here.

Vivid LEDs: Special Color Rendering With Spectrum Tuning

When we talk about color rendering, traditionally that conversation has been filled with CRIs and Ra-indexes. These traditional ways of telling how well certain light source represents sunlight have been criticised because they may not tell the whole truth.

In recent years, LED manufacturers have been trying to answer this criticism by creating different products. Terms like “premium white”, “crispy white”, “pearl white” and “vivid white” have come to LED markets.

Despite the different terms, they are all meant for the same purpose: To represent certain colors and make the lighting look better. I will be using term “Vivid” as it is the term Citizen Electronics uses. And to be honest, it describes the purpose of these LEDs quite well.

Color rendering

Color rendering means simply how well a white light source can show, or render, the true colors of different physical objects compared to sunlight. You know the effect when you buy a jacket in the clothes shop and it looks completely different in sunlight.

Colors are divided into 15 indexes (R1-R15). A general color rendering index (CRI or Ra-index) is defined as an average of the sum of first eight indexes (R1..R8). However, these first 8 indexes are rather less saturated colors, while indexes R9-R12 represent highly saturated colors (red, yellow, green, blue).

CRI 100 = Sunlight

For example, in grocery stores, a shopkeeper may want to highlight red color of meat or colors of vegetables. This means that the general color rendering index doesn’t really tell anything about the rendering capabilites of the light. In this case, high rendering index of some of R9-R12 indexes is necessary. It doesn’t matter how high the CRI is, R9-R12 can be anything.

CRI 83 (look at R9)

CRI 83 (look at R9)

The above image shows the index values of R1-R15. The CRI is 83, but look at the R9 value. Not very good.

So basically, the LED itself can have the CRI of 97 and you still have no idea how does it render red or green for example.

Vivid via Spectrum tuning

Vivid LEDs are made using spectrum tuning. In short, this means that the phosphorus of the LED has been modified. How it is modified, depends on the LED and the intended application. Note that spectrum tuning can be made also by using RGB-LEDs.

For example, Vivid White LED’s spectrum has been tuned so that it represents white and bright colors as well as possible. The colors are more saturated than under typical normal LED light.

Test report on Vivid White aLED Module

Test report on Vivid White aLED Module. Click the image to open it in new tab for better view.

These LEDs work very well for example, in clothing stores, where you have a lot of different colors that need to look good.

Here are two good principals when choosing LED:

  1. Think about your application, what colors do you want to highlight?
  2. Don’t stare at the CRI (unless you get a full report), it might not tell everything

Conclusion

Traditional way of thinking color rendering solely through the CRI should be updated. More importantly, you should know what you want to highlight and ask for a LED suited for your application.

Download More Information About Vivid

 

How to use Citizen LED simulator

Datasheets are essential part when you compare how different light sources work in your solution. Usually it can be time taking and exhausting to glance at datasheet and find values you are looking for. This gets even harder if you have multiple LEDs or different LED packages, which would mean that you have look at multiple datasheets to get different values.

This is the reason why Citizen has created a Citizen LED simulator. The simulator is very easy to use and makes comparing different LED packages a lot easier. If you haven’t yet tried it or you don’t have the simulator, you can download it for free from our website.

Citizen LED simulator basic view

Citizen LED simulator basic view.

The steps

Follow these steps to use the simulator.

You can choose desired CCT and Ra and selection simulator shows packages and product codes of existing products.

You can choose desired CCT and Ra and selection simulator shows packages and product codes of existing products.

  1. Select the CCT and Ra

First you need to select desired CCT and Ra from condition input field.

You can choose desired CCT and Ra and the selection simulator shows packages and product codes of existing products.

  1. Choose whether you want to search based on the desired lumen amount or driving current

After you have selected color temperature and CRI value, you can choose between driving current (forward current in simulator) or desired luminous flux.

  1. Input the Tc-temperature

Then you can input Tc-temperature. If you have no idea how much Tc is or would be in your solution, values around 60 degrees are realistic to use as many light sources reach temperatures close to that while being used.

Example

In this example, I have chosen that I want my LED to be 4000K, Ra80 Min. And I want to see what options we have to get around 3000 lumens out from luminaire. Luminaire optics etc. will drain around 300-400 lumens in my solution. So I have determined that I need 3400 warm lumens from LED and estimated that Tc-temperature is 60 degrees.

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I can see that I have ten different LED packages I can get the 3400 lumens from. In first column after product code you can see what current you should use to get these values. If you don’t have LED driver, in which you can choose output current, it is recommended to then select current value you have LED drivers available in. In this case, 700mA seems to be a good choice as many of the LED’s have driving current close to that.

So I change “forward current” instead of “luminous flux” from the condition input and insert 700mA.

LED packages which give you desired lumens with 700mA. We still have six options to choose from.

LED packages which give you desired lumens with 700mA. We still have six options to choose from.

This will give me a list of LEDs I can use with 700mA driver. And more importantly give me a good overview of LED packages that can give me my desired lumen amount. If you have problem that you can’t find driver with suitable current, you can contact me for help.

In this case, CLU028-1204 would suit my lumen need quite nicely and CLU048-1212, would probably be an overkill for this application. All the other options, might suit my solution although they give roughly 10% more lumens. Whether this is ok, depends really on my application and desired efficacy.

Other applications

Citizen LED simulator is also powerful tool to use when you want to see easily how much lumens you get when driving LED with different currents. Good example is that if you have LED driver which has different current options and flexible LED package, you can use only two components to realize many different lumen packages.

As an example I did this exercise with ELT 42W multicurrent LED-driver and Citizen CLU038-1205 LED package. This driver has option to select different driving currents with dipswitch. If we take Esko’s advice and look from driver datasheet, we can see that output voltage area is suitable from 500mA to 1000 mA.

Below you can see LED characteristics with different current. I have also added forward current column to make this table easier to read. Tc temperature is 60 degrees in all cases.

Table with CLU038-1205 4000K Ra80 LED from 500mA to 1000mA.

Table with CLU038-1205 4000K Ra80 LED from 500mA to 1000mA.

You can also use the LED simulator to estimate the amount of lumens lost due to your luminaire (optics etc.). If you measure LED Tc-point and input the driving current you use to simulator, you should have pretty good estimation that how much lumens you should get out from your luminaire.

If you find out that the loss is too big, the you can either change the LED to a different package or improve the optics of your luminaire.As you can see, you can use this driver & LED combo for a luminaire from ~2500lm to ~5000lm.

Please feel free to contact me if you have any questions.

You can download the latest simulator below.

Download COB Selection Simulator