Datasheet

Product specifications and configurations, and availability of products are subject to change. Variations in product
design and product features are subject to change. Colours may vary from illustration. Errors and omissions excepted.
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GLOSSARY
Dimming of lights
LED lights can be dimmed without sacrificing
light quality. This is the main difference from lights
fitted with fluorescent or high-pressure discharge
lamps. Dimming also saves more energy. There are
different types of dimming.
DALI
Luminaires are controlled by the digital DALI (Digital
Addressable Lighting Interface). This standard, adopted
by all manufacturers, overcomes the disadvantages
of the 1 – 10 V principle and is being used in-
creasingly, particularly in more complex installations.
DALI offers a two-wire line that is protected against
polarity reversal, with noise-resistant digital signal transmission,
direct addressability, compact instruction set, error feedback and
defined brightness values which are independent of line length.
DALI is also supported by building and light management systems.
1 – 10 V
Luminaires can be dimmed via the 1 – 10 V interface.
A voltage level between 1 V and 10 V is converted into
corresponding lamp brightness.
CONSTANT LUMEN OUTPUT
Constant luminous flux over the life of the lamp
The drop in luminous flux due to the LED technology over the
service life of the system is compensated by increasing the
power input. This results in constant and uniform photometric
performance differentiating strongly TOSHIBA products from
standard LED systems whose lumen output drastically drops over
time lighting.
DALI
DIMMABLE
DIMMABLE
1 –10 V
DIMMABLE
10 –100 %
DIMMABILITY
TIME
POWER
CONSUMED
=> DECREASING PHOTOMETRIC PERFORMANCE
ENERGY WASTE
WITHOUT CONSTANT LUMEN OUTPUT
ENERGY WASTE
LUMINOUS FLUX
TIME
POWER
CONSUMED
=> STABLE PHOTOMETRIC PERFORMANCE
OPTIMUM POWER CONSUMPTION
WITH CONSTANT LUMEN OUTPUT
ENERGY SAVING
LUMINOUS FLUX
Basic Photometric Units
There are several photometric base quantities in the definition of
light sources, which characterise different qualities.
Luminous flux ϕ in lm (Lumen)
The total radiating power emitted by a
light source, which the eye perceives as
light.
Luminous intensity I in cd (candela)
The luminous flux of a light source per
solid angle. With the same luminous flux,
the light intensity increases the more the
light source focuses the light.
Illuminance E in lx (Lux)
A measure of lighting power per lit
surface. A minimum luminance is spe-
cified for many visual tasks and must be
considered in the planning of the visual
task and choice of light source.
Colour Rendering Index Ra
Colour Rendering Index (CRI) is a measure of how well a light
source is able to accurately reproduce colours of objects being lit
respective to the colour temperature (CCT) of the light source. The
higher the colour rendering index, the more naturally the colours of
an object are reproduced and therefore perceived by the observer.
The sun has the highest CRI of 100. Most artificial light source
are below that. The colour rendering index is determined using
8 standardised test colour references.
Dimmability by trailing edge phase control
Luminaires can be dimmed very easily using trailing
edge phase control. The advantage of trailing edge
phase control compared with circuits in which the
voltage is controlled by a resistance is that they have
a very low power loss and are widely used in existing
installations. The main disadvantage of trailing edge
phase control is the non-sinusoidal current profile. Because current
and voltage do not have the same shape, so-called distortion
reactive power occurs. Shifting the current backwards compared
with the voltage curve has the same effect as an inductive load,
which electricity supply companies can only tolerate at low
power levels. Leading edge phase control is not recommended
for Toshiba lamps. Because there is no general compatibility
between all dimmers available on the market, Toshiba
has provided a list of recommended dimmers on its website
www.toshiba.eu/lighting.
Colour temperature (K Kelvin)
Colour temperature is a measure of the colour effect of a light
source. Colour temperature is defined as the temperature of
a black body which belongs to a particular light colour of this
emission source.
Typical colour temperatures for light sources are:
• below 3300 K = warm white, preferred for interior lighting
• 3300 K to 5300 K = neutral white, typical light colour for office,
industrial and exterior lighting
• above 5300 K = cool white, especially common in exterior
lighting.
L70 service life of LED light sources
LEDs are characterised by their excellent service life. Because
LEDs hardly ever fail completely, the service life is defined as
having an L70 value. Their useful life is considered to be over when
the luminous flux has dropped to 70% of the initial luminous flux.
After this time the LEDs age at a dramatically accelerated rate.
The service life of an LED light source is not set by the LEDs alone,
the other electrical components and the thermal design are also
a factor. Therefore the given service life varies from product to
product.
Power factor λ = cos ϕ
The LED light sources need driver modules to operate which act
capacitively from an electrical point of view. This leads to a phase
shift between voltage and current consumption and consequently
the apparent power S (given in Volt Amperes VA) has an effective
power proportion P (Watts) and a reactive power Q (Volt Ampere
reactive VAr). The relationship between effective power P and
apparent power S is represented as the power factor λ.
LUMINOUS INTENSITY (l/cd)
LUMINOUS FLUX (Phi/lm)
ILLUMINANCE (E/lx)
Distancer
cd
DIMMABLE
10 –100 %
GLOSSARY
Re (S)
VECTOR DIAGRAM OF APPARENT POWER S
S (VA) = Apparent power
P (W) = Eective power
Q (VAr) = Reactive power
ϕ Phase shift in °
P
––
S
COS ϕ =
lm(S)
ϕ
Service life (h)
x0
100%
- 30%
70%
Hours
Relative luminous ux (lm)
AGEING OF LED LAMPS
L70
Phase control
Phase control widely used for incandescent and halogen
lamps dimming this analogic control method apply also
to LED lamps. Because there is no general compatibility
between all dimmers available on the market, Toshiba has
provided a list of recommended dimmers on its website
www.toshiba.eu/lighting.
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