The i-save energy glossary


C:     CE, Color rendering, Cooling

D:     DALI, Dimmability

E:     Electronic ballast, EMC, Emergency power systems, ENEC, Energy efficiency

F:     Fixture, Food compatibility

K:     Kelvin, KNX

L:     LED, Level of illumination, Life span, Light color, Luminous efficiency, Luminous flux

M:    Mercury

P:     Protection class

R:     Ra value, Reference value, Replacements

S:     Safety lighting, Starting performance, Start-up time, Surge protection, Switching capabilities

V:     VDE

W:    Workplace regulations



CE marking is not a test seal, but an administrative mark which enables industrial products to be traded freely in the single European market. According to EU Regulation 765/2008, CE marking indicates "that a product is in conformity with Community harmonisation legislation."
Those who manufacture industrial products verify that they comply with current EU guidelines and apply the CE mark to their products at their own liability.


Color rendering

The Ra value indicates how colors are reproduced realistically by lighting. The color rendering index (cri) defines a range between 50 and 100 Ra. The highest value is reached by sunlight. Thus, the best color reproduction is achieved. LED fixtures currently achieve values between 70 and 90 Ra. DIN EN 12464-1 defines Ra values for specific areas of activity.



Cooling plays a decisive role concerning LED fixtures – the higher the ambient temperature the lower the life span of an LED. The lifetime of an LED constitutes a crucial factor regarding economic efficiency.


DALI (digital Adressable Lighting Interface)

DALI is a protocol for managing lighting systems and equipment, such as electronic ballasts. Such devices must have a DALI interface, via which a DALI control module can both check the device status and govern its output. In standalone systems, DALI can control up to 64 devices individually. DALI control systems are available in both wireless and wired versions.



Not all LED fixturess are dimmable. The appropriate information about dimmability and the use of certain dimming systems (0–10 Volt, KNX or others) are available on the technical sheets of the LED fixtures.


EMC (Electromagnetic compatibility)

EMC means technical products are not vulnerable to interference and do not generate any interference themselves by generating electrical or electromagnetic emissions. In industry, LEDs are generally used in an electromagnetic environment, so they need to be EMC-tested. This is done by the manufacturers or test bodies.



ENEC certification guarantees that products meet European safety standards. Products are tested and certified by accredited institutions. ENEC certification covers the standards of all the European countries involved, including VDE standards in Germany.


Electronic ballast

LED fixtures require an electronic ballast that provides a constant supply current (350 or 700mA). Ideally, the actual ballast and the body of the fixture are installed physically separated because of the heat production.


Emergency power systems

Sensitive areas and emergency escape route lighting must stay on, even if the general power supply fails: so batteries or generators are used . As batteries work on DC, the lights used must be able to run on this. i-save LED lights work on both AC and DC in principle. Statutory emergency lighting requirements can be found in EN standard 1838:2013.


Energy efficiency

LED fixtures usually achieve the energy efficiency Level A to A++ (EEL).



A fixture consists of a light body and the illuminant (lamp).


Food compatibility

Food processing companies must use special lights, which are subject to IFS (International Food Standards) rules. Lights in such areas must be fat-, solvent and cleaning agent-resistant, splinter-proof and fitted with suitable fire protection.



Kelvin (K) indicates the light color of an LED fixture. While incandescent and halogen lamps can only give warm white light because of their construction, LED light can generate all white light colors from below 3000 K (warm white) to way above 6000 K (cool white).



KNX is an open standard for building systems, which can be used to manage a range of KNX-certified systems (heating, lighting, ventilation etc.). No central control is required, as each device has its own processor which records the appropriate input factors, e.g. daylight via sensors and activates relays for dimming etc.. Sensors and actuators are connected via a bus line.



The lamp is the part of a fixture, that emits light.


Level of illumination

How much light hits a certain surface? This value (in lumen/m2) is important for planning the right type and amount of fixtures in order to reach the claimed luminous flux (lx). According to DIN EN 12464-1 there are special Lux standards for workspaces and areas of activity– in hall lighting for example, at least 300lx have to be assumed.



The term LED denotes light-emitting semiconductor diodes. If electricity flows through a semiconductor, light is generated. Today’s LED fixtures do not have much in common with the LEDs from the 60s that were used for displays or signal lights. The enormous increase in efficiency and the method to produce white light, , developed in the 90s, empower the LEDs to be usable for high bay lighting and similar applications.


Life span

The life span of LED fixtures is ranging from 20.000 to 50.000 operating hours and beyond. To compare: incandescent lamps have an average life span of 1.000 hours, halogen lamps of 3.000 hours and energy saving lamps of 10.000 hours.


Light color

The unit Kelvin indicates the color of light. The lower the value in Kelvin, the warmer the light appears, due to the higher red spectral content. The spectrum of white light from LED fixtures ranges from under 3000 K (warm white light) to about 6500 K (cold white light).


Luminous efficiency

The specification for the light output is lumens per watt (lm/W). It associates the values of energy consumption and light output. The higher the amount of lm/W the higher the efficiency of an LED. For industrial fixtures that are used as high bay lighting, values of over 120 lm/W can be achieved.


Luminous flux

The entire output from a light source (colloquially one can speak of the brightness of the light) is called luminous flux and is measured in lumens (lm). The former practice of giving the level of performance in watts does not apply for LED. The notation for the level of performance according to LED is replaced by lumens.



Mercury is a component of many energy-saving lamps. If the mercury escapes it might cause health damage. LED lamps are completely mercury-free.


Protection class

The protection class of an LED fixture indicates the extent of protection against the penetration of solids and water. The protection class is expressed as IPxx.
A fixture with IP65 protection for example is dust-proof and protected against the ingress of water jets. When used in industry or logistics the protection class of an LED fixture is a crucial factor.


Ra value

The Ra value indicates how colors are reproduced realistically by lighting. The color rendering index (cri) defines a range between 50 and 100 Ra. The highest value is reached by sunlight. Thus, the best color reproduction is achieved. LED fixtures currently achieve values between 70 and 90 Ra. DIN EN 12464-1 defines Ra values for specific areas of activity.


Reference value

On most LED lamp packaging one can find the reference value to facilitate comparison with the earlier standard specified in watts for the brightness of a lamp.



LED lamps that directly replace older lamps are called replacements. These include lamps with GU10, GU5.3, E14 or E27 sockets as well as LED tubes as a substitue for fluorescent tubes.


Safety lighting

See emergency power systems.


Starting performance

In contrast to energy-saving lamps and fluorescent tubes, LED fixtures reach their full brightness immediately after turning-on.


Start-up time

The start-up time signifies the period of time until a lamp provides 60 percent of its brightness value. LED-fixtures do not require this start-up time.


Surge protection

Lightning strikes, static discharges and connecting new electrical systems can cause electrical networks to surge, which can damage or destroy electronic equipment like LEDs. Professional surge protection is therefore required by way of upstream circuit breakers in industrial applications.


Switching capabilities

LEDs can be turned on and off almost unlimitedly. Therefore, the issue of switching resistance plays only a subordinate role.



Electrical products do not have to be certified by VDE (Verband der Elektrotechnik Elektronik Informationstechnik e.V.), the German Association for Electrical, Electronic and Information Technology, contrary to what people in this country generally believe. Being VDE certified indicates that products comply with statutory requirements and also with VDE standards and those of other international organisations in terms of electrical, mechanical, thermal, toxic, radiological and other risks.
VDE standards only apply to Germany, and include ENEC certification which applies at European level.


Workplace regulations

German workplace regulations implement EU directives on safety at work, and also include rules on workplace lighting. These can be found in DIN EN 12464-1, which specifies a range of lux values required for specific visual work etc. in detail.


Further information on LED.