3.3 Influence of harmonic waves and corresponding filters. Osram HQI-E 150 W/NDL CL
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supply and, above all, a clearly reduced tendency to go out by avoiding re-ignition peaks all lengthen the lamp economic life for ceramic arc tube lamps by up to 30% on average.
current of the electronic ballast, producing a higher wattage input into the lamp which therefore heats up more quickly.
Permanent monitoring of parameters such as lamp voltage or lamp current by the integrated micro-controller and alignment with pre-defined nominal values also makes it possible to turn lamps off well before they reach critical or undefined conditions which often can hardly be managed.
3.2.3.4 Size, weight and handling
The electronic ballast also shows its strengths at the end of the lamp service life. The ignition time limit ensures that old lamps, where stable operation is no longer possible, are not subject to endless ignition attempts. After max. 18 minutes and precisely defined ignition intervals, the POWERTRONIC ® ECG cuts out automatically. If a lamp goes out 3 times, the electronic ballast also cuts out. This avoids interfering, flickering light, prevents EMC load on the cables and also an excessive load on the electronic ballast itself.
Electronic ballasts combine ignition component, compensation component and choke in one unit. This
3-in-1 combination clearly reduces the installation workload, the risk of installation errors and the need to replace individual faulty units. Multi-lamp electronic ballasts (e.g. 2x35 W or 2x70 W) duplicate these advantages because to connect to 2 luminares, only one power lead is required.
Electronic ballasts are also lightweight. They weigh
50% to 60% less than magnetic ballasts, which of course offers direct advantages in terms of luminaire design: they can be sleeker in structure; a wider range of materials can be used, and a lighter load can be placed on the fastening components.
3.2.3.5 Bidirectional data transfer
3.2.3.3 Light quality, light colour, drop in light output, start-up
HID lamps with electronic ballasts offer considerably improved colour quality, both when initially installed and throughout the service life.
The constant wattage supplied to the lamp by the electronic ballast can compensate for differences in light quality resulting for example from production tolerances or differing aging states. The result is visibly more even light colour and a more uniform chromaticity coordinate.
Intelligent electronic units will in the future offer completely new possibilities of controlling and monitoring lighting systems, thanks to bidirectional data transfer.
Features such as querying the lamp or ballast status, integration in Building Management Systems (BMS) and central or local actuation and management of lighting solutions will not only bring a clearly expanded range of functions but also optimize maintenance and repair work. In the medium term, it is quite conceivable to see developments here similar to those in low-pressure discharge technology.
Similarly, supply voltage fluctuations or the length of the power leads are no longer relevant when using an electronic ballast, as the constant wattage supply to the lamp means these have no effect.
• Electronic ballasts are state of the art.
• Electronic ballasts can be used to achieve significant increases in quality, reliability and safety of lighting systems with metal halide lamps.
Lamp electrodes cool down to a lesser extent with the rectangular electronic ballast thanks to the steep electrical transitions through the zero crossing. Less cooling down results in reduced sputter effects of the electrodes, which in turn means less bulb blackening.
The more constant, and on average slightly higher, lamp plasma temperature also produces 3% to 5% more luminous efficacy, which also has a positive influence in luminous flux behavior in addition to reduced blackening effects.
• Most new MH lighting installations today are already equipped with electronic ballasts.
3.3 Influence of harmonic waves and corresponding filters
Electronic ballasts also have a much faster start-up behavior than magnetic ballasts. Fig. 24 in chapter
4.7 for example clearly shows that a double-ended quartz lamp operating with an electronic ballast already produces more than 90% of its max. luminous flux after approx. 40 seconds. The same luminous flux level with a conventional ballast takes at least 25 to 30 seconds longer. This at least 50% faster start-up at the electronic ballast is due to the higher start-up
The development of modern semiconductor technology with a significant increase in the number of consumers with solid state switches and converter controllers unfortunately results in undesirable side-effects on the
AC voltage supply by causing considerable inductive wattless power and non-sinusoidal current.
A typical converter current consists of various superimposed sinusoidal partial currents, i.e. a first harmonic with the supply frequency, and a number of
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