Does Duralamp produce energy saving lamps with different bases from those shown in the catalogue?
All the mains voltage Electronic Energy Saving lamps can be supplied, on request and in quantites, also with 110-120V, 240-250V and with B22, B15d, E26 or E12 bases.
When should I use a halogen lamp with a dichroic reflector and when is it better to choose an aluminized reflector?
The dichroic treatment reflects the visible rays, whereas the infrared rays, with a high thermal content, are not reflected by the reflector and, therefore, do not become concentrated on the objects illuminated.
The word derives from the Greek “dicroos”, two colour. It involves a very thin (0.1 micron) film of material with different refractive indexes being deposited on a faceted glass: the rays on the visible band are duly reflected by the reflector and concentrated forwards, whereas the infrared rays do not undergo any appreciable reflection and continue their path towards the opposite part. In case this effect should not be suitable, it is necessary to use lamps with an aluminized reflector: the aluminizing stops the infrared rays passing towards the back of the lamp, thus protecting the luminaire and the electrical components from heat. This solution is recommended in cases where the space in which the rear of the lamp is housed is very small, for plastic appliances, etc..
Why Xenon halogens last longer than regular halogens?
All the Xenon lamps are an evolution of halogen lamps: this gas, inserted inside the bulb, drastically reduces the main causes which bring the life of a halogen lamp to an end, i.e. the breakage of the filament due to wear.
Technically, the greater atomic weight of the Xenon creates a gaseous sheath around the filament: this means that the tungsten evaporating from the filament due to the high temperature is deposited back on the filament itself, thus rebuilding it.
By reducing this wear factor, the life of the lamp is considerably extended.
I have purchased white light dichroic lamps but have the impression that the color of the light changes: is this possible?
Yes, it is possible because variations in voltage can cause changes to the color tonality. It is, therefore, necessary to check the voltage.
On an installation featuring a lot of halogen lamps, the lifetime of the same seems much shorter than stated: why is this?
It is probable that the problem is caused by overloading. Variations in input voltage can directly influence many of the lamp’s initial data, including its lifetime. Even a limited increase in voltage can drastically reduce lamp life. This is clearly explained in the graph: the voltage is shown horizontally, with 100 as the nominal value. A 6% increase in voltage, i.e. to 106, modifies all the values with respect to those initially defined and the lifetime is reduced to 45% of the nominal value! So you should check the voltage.
Is luminous flux dependant on the temperature of the environment?
The light output of a fluorescent lamp depends on temperature. There is an optimal temperature at which the light output is maximised: below and above this temperature, the lumen flux is tesser than what declared. The reason for this behaviour is complicated and it is determined by the antagonism of different phenomena that involve the internai pressure, the tension of mercury vapour and other factors. The graph shows the behaviour of the luminous flux of a linear fluorescent lamp with variations of temperature: the lamp will not supply the stated nominai flux where temperatures are outside the optimum. Lamps installed in closed appliances without ventilation might therefore supply a very low light flux, in addition to having a reduced life span. The ignition of the lamp is also influenced by temperature. Below a certain value, normally -15°, the ignition of the lamp is more difficult and the lamp may not ignite all together.
What happens to an incandescent lamp and, thus a halogen lamp, if the voltage varies?
The initial data required for a lamp project are the voltage, power, fife and luminous flux. The graph shows the behaviour of each of these parameters in relation to the voltage.
The percentage variation of the voltage from its nominal value, indicated by 100%, is shown horizontally. For example the number 96 corresponds to a voltage reduced to 96% of its nominal value.
Vertically, the current, power, efficiency and flux variation percentages are shown on the left, and the % lifetime with respect to the nominal value indicated by 100% is on the right.
The graph shows the effect of a modest voltage variation, +6 % (see broken vertical line at 106): the duration of the lifetime is reduced to 45% of the nominal value!
Which starter should I use for my fluorescent lamp?
A starter table is provided in the product description: for your information, a copy of the table is provided below.
Which type of transformer can I use with LED lamps?
All electromagnetic transformers (12V nominal voltage) can be used with Duralamp very low voltage LED lamps. If you want to use an electronic transformer, please refer to the enclosed table.
How do we define the average life of a LED lamp?
IESNA* standards do not define the nominal life of a LED lamp as being from the moment in which a half plus one of the items in a sample lot ceases to function (as for other lamp types), but rather from the time when a half plus one of the light bulbs presents a decline in luminous flux of over 30% for lamps used for “general lighting” and 50% for “decorative” lamps. Duralamp guarantees a nominal average life of 15000 hours, at standard ambient temperatures, for most of the models in the catalogue. By taking certain precautions with the circuitry, it is possible to extend the life of some lamps to 25000 hours. It should be noted that, as for any other lamp, the average life of a LED lamp depends on the operating temperature. The use of lamps in recessed or closed fixtures, or fixtures which do not have an adequate exchange of air, as well as any other conditions that raise the operating temperature, can reduce their actual lifetime.
*The standards of the Illuminating Engineering Society of North America are the main reference standards currently being used by sector industries until European directives have been issued on this subject.
What is colour rendering?
The colour rendering of a light source is the effect that the source has on the appearance of the colour of the objects, in comparison with their colour appearance under a reference light source. In order to obtain the best rendition of all the colours, a light source should have the most complete possible emission spectrum. The colour rendering index gives an idea of the faithfulness of the rendition of the colours by the source. Lncandescent and halogen lamps have the best colour rendition, measured with a Colour Rendering lndex of Ra=100; amongst the fluorescent lamps, Duralamp's triphosphor lamps have very high colour rendition levels, Ra>85.
What is COLOUR TEMPERATURE of lamps?
This is the term used to quantify the light tonality generated by a light source and is measured in kelvin degrees, K. Since light ‘creates’ the ambient in which we live, the colour temperature of light causes psychophysical reactions which must be taken into account.
(2700K-3000K) - a light with a “warm” colour temperature creates a relaxing and welcoming environment: home - restaurant;
(4000K) - “natural” colour temperatures generate highly dynamic effects and are more suitable for working environments: offices, stores, shopping malls;
(6000K-6500K) - “cold” colour temperatures are preferable for ambients in which a high level of attention and efficiency is required: laboratories, hospitals.
How can I choose the most suitable ‘light color’ for my environment?
The choice of a certain type of light source and its characteristics is linked to the environment and the effect to be created, the functions to be carried out, the quantity of light necessary, as well as psychological components. For example, in countries with strong sunlight, such as those located in the Mediterranean area, an attempt is made to recreate the type of outdoor light found in indoor environments, choosing lamps with very high colour temperatures (6000-6500K) and a strong intensity. Conversely, in countries with a lower amount of sunlight, such as Northern Europe, a more suffused indoor light is preferred, with lower colour temperatures (2700-3000K).
Therefore, any indications about the type of light to be used require a careful analysis of the relevant environment (whilst confirming the above guidelines) and the experience of those working in this sector.
How many PAR56 swimming pool lamps can be installed at a time?
There is no limit to the number of lamps: the only limitation regards the charge of the transformer.