SICCE LED Lighting Systems

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1 SICCE LED Lighting Systems FAQs Q. What is the lumen output per LED? A. 20 lumens per individual LED Q. What is the wattage per LED? A watts per LED Q. What is the total power consumption of the unit? A. MINU = 20 watts AM366 = 60 watts AM650 = 180 watts AM466 = 120 watts Q. What type of LEDs are used in the unit? A. MINU: 72 White K and 4 Actinic Blue 446 nanometers AM366: 196 White K and 14 Actinic Blue 446 nanometers AM466: 392 White K and 28 Actinic Blue 446 nanometers AM650: 588 White 12,000-14,000 K and 42 Actinic Blue 446 nanometers These choices were made because typical units use 7000K white LEDs and must combine them with 50% blue to obtain the desired Kelvin temperature. Our unit uses a 12-14,000K LED and consequently uses 80% white and 20% blue. This gives the maximum lumen output with minimum electrical consumption at the desired overall color temperature. Q. What is the warranty on this unit? A. Five years Q. What is the PAR value of this fixture at different levels in the aquarium? Photosynthetically Active Radiation, or PAR, as it's commonly called, is a term that's widely used in the aquarium hobby, and is often not well understood, especially when applied to LED lighting. When used correctly, PAR information can be very helpful in determining the best way to light a reef aquarium, and where best to place corals, clams, and other photosynthetic invertebrates. When misunderstood, it can lead to unnecessary and costly lighting purchases and have detrimental effects on your reef aquarium! [1] PAR is important because it is roughly the measurement of how much usable light energy is available to your corals and other reef tank inhabitants. PAR measurements, taken with an underwater PAR meter, allows determination of the exact amount of light the aquarium receives. Both too little and too much light can have negative consequences for photosynthetic organisms. Therefore, achieving the correct level of illumination throughout the aquarium is an important key to success. PAR values are most easily visualized by three dimensional graphs that show the light distribution over the entire area being illuminated. The graphs for many of the lighting systems on the market are in the shape of a

2 pyramid, i.e., PAR values are highest in the center directly below the light source, even reaching levels that many consider dangerous for corals. The PAR value drops off dramatically as one moves away from the center. This is done in order to achieve desirable PAR values on the surrounding area, but often only a few inches away from the center. At the edges of the tank, the PAR drops to nearly zero. What SICCE has done in order to solve this is to design a unit that produces a uniform curtain of illumination that achieves maximum PAR values over the entire tank area, not just in the center. AM 366 PAR cm 0 40cm 20cm 0cm 20cm 40cm 10cm Evaluation of PAR Value Distribution for Sicce LED Lighting Systems The first set of data was measured under a worst case scenario. That is, in an established aquarium, in a dark room, at 50 cm (19.7 in.) above the of the tank. This is a realistic set-up for a field test, and I believe that we have a product that is unique in the market! The coverage and homogeneity of light intensity over the entire tank is impressive. We are suggesting the AM366 model for a tank of maximum length of 60 cm (23.65 in.) but PAR values >100 were measured even at 40 cm (15.75 in.) from the center. Therefore, the unit could actually be used for larger tanks. Our technology and design have resulted in LED lighting systems that use less energy to illuminate the largest possible aquarium size, with an even distribution of light over the entire tank area. Energy use is minimized by optimizing LED output. The number and arrangement of LEDs insures that homogeneous light will reach all corals in the tank. Measurement taken from SICCE USA: Measurements for the AM466 taken underwater at 23 inches below the unit yielded a PAR value of 245 (µmol photons/m 2 /sec). This compares favorably with readings taken in air at the same distance from a 250-watt metal halide lamp. Readings taken at other points were as follows: 7" directly below the unit PAR = " right of center and 23" deep PAR = 104 9" forward of center PAR = 226

3 Q. What is the PUR spectrum of the unit? A. PUR is difficult to measure and varies from one species to the next. The most useful comparison is between the absorption spectrum of chlorophylls a and b and the emission spectrum of the light source. The graphics below show, top and bottom, the chlorophyll absorption spectrum and the emission spectra for one of the two types of LEDs used in our unit. A comparison of these spectrographs shows that our blue LEDs emit strongly in the ~450nm range, corresponding to the intersection of the chlorophyll blue absorption peaks. The middle graphic shows emission spectra for two types of white LEDs with Kelvin temperatures lower than those of the LEDs in our design. From this graph it can be seen that the higher the Kelvin temperature the more energy is emitted on the blue end of the spectrum, where chlorophyll absorbs most strongly. Q. How does this compare to metal halide? A. Examine the graphic below, which appeared in an online Aquarium Digest article. It compares a generic LED unit with both chlorophyll absorption and a generic metal halide lamp. As you can see, the light energy from the metal halide is more widely spread across the whole visible spectrum, while more of the LED energy is concentrated in the wavelengths most useful to reef organisms, i.e., those absorbed by chlorophyll. You can see the purple line in the graph (metal halide) shows the strongest peaks in the nm range, in between the absorption peaks for chlorophyll. This is why, even at a lower lumen output, the LED unit provides superior illumination for photosynthesis.

4 Q. Why don't we use fewer higher lumen output LEDs? A. To obtain the desired light output, the design uses a larger number of LEDs and supplies them with nominal current per manufacturer s specifications to obtain the maximum useful lifespan of 10 years as claimed. Competing units use fewer LEDs and run them at maximum allowable current. This achieves the lumen output with fewer LEDs but lowers the overall lifespan of the unit. A simple comparison is the difference in durability of a car engine driven normally versus one driven always at racetrack speeds. The latter wears out a lot sooner, as any pit crew can attest. The unit is designed to imitate natural sunlight in the most realistic way possible. By utilizing a large number of LEDs, we eliminate the curtain effect that highoutput LEDs usually create as a result of their spaced out distribution. Q. Is this unit energy efficient? A. Comparing the AM466 (120 watts total power consumption) to a 175 watt metal halide lamp yields an energy savings factor of 20%. For the AM650 the comparison of 180 watts to 250 watts of metal halide reveals the LED unit is about 28% more efficient. Because metal halides waste approximately 50% of their energy output in radiation that is not actually utilized by reef organisms (see PUR discussion above), the effective efficiency comparisons are approximately double those given for illustration purposes. For a dollar comparison of the AM650 using TVA residential electric rates, 180 watts for 50,000 hours is 9000 kwh, or about $810 worth of electricity over the life of the unit. For 250 watts of MH incandescent for the same time period, the cost is $1125, not counting the cost to replace the lamp at least once during that time. With the lamp cost included, the savings total about $350 over the life of the LEDs. NOTE: Because TVA power rates are among the nation s lowest, savings in other parts of the country will be higher. The calculations were based on a residential cost of 9 cents per kilowatt-hour. Q. In terms of efficiency, how does your unit compare to other LEDs? A. It is important to remember that our design utilizes white LEDs that are guaranteed by the manufacturer to emit in the 10,000-12,000 K range. These LEDs cost more than those with lower Kelvin temperature, but their use permits us to have fewer blue LEDs to achieve the desired overall color temperature of 14,000 K. The reason we wanted to use fewer blue LEDs is that they waste a lot of energy, not being as efficient as the white LEDs are. Our unit therefore makes the most of the watts it absorbs, because 80% of the output is from the white LEDs. Also, our power packs are cutting-edge in efficiency, so only a very small percentage of watts is wasted in the conversion of the supply voltage to operating voltage. When comparing our unit with theirs, competitors may claim a higher efficiency based upon lumen output per watt of electricity consumed. However, the relationship between power consumption and lumen output for LEDs is non-linear. Higher-wattage LEDs are less efficient, not more so. As the wattage absorbed increases, lumen output does not increase proportionately. For example, at one watt the output might be 100 lumens, but at 2 watts the output will only increase to 170 lumens, not 200 as might be expected. To obtain the desired color temperature, all manufacturers of aquarium LED lighting units must use a combination of blue and white LEDs. Competing units frequently use a ratio of blue to white LEDs that approaches one-to-one. In order to achieve the same total lumen output as our unit, therefore, they must use many more LEDs, and thus the units consume more energy.

5 Q. Why can you not change out the LEDs when they go out? A. The individual LEDs are first glued, then soldered to the circuit board and the whole thing is encased in waterproof plastic. This automated process is far cheaper than installing individually removable LEDs. The high-output LEDs used in the unit cost more than standard components. Automated assembly means these better LEDs can be used without increasing the cost of the unit. The circuit boards consist of an aluminum base layer with the electric circuit printed on top, separated from the aluminum by a thin layer of insulating material. This design guarantees maximum thermal transfer from the electrical components to the aluminum base. It was chosen because, in order to last, LEDs must operate at the lowest temperature possible. Above all, excess heat that accumulates inside them must be dissipated. Some designs rely on ventilation fans to dispel heat, but this will not guarantee the proper temperature for the LEDs themselves. Another benefit to eliminating the need for a ventilation fan is that the unit is completely silent, as it contains no moving parts. This also eliminates the need for maintenance, such as cleaning dust from ventilation openings. Further, the unit can be made completely watertight, since no air flow channels are required. Q. Without a fan, how can you avoid heating the aquarium water? A. The thick layer of acrylic that separates the electronic components from the water surface is not only an aesthetic and design component, it acts as an insulator, preventing radiant heating of the water. Q. How well does this unit stand up to moisture conditions around the aquarium? A. Our lighting system is one of the few that is totally immune to humidity and to splashes of water, since it is built with a double O-ring that makes it watertight, preventing any possibility of water coming into contact with the electrical components. The connector and power cable are watertight, too. Q. Do you have evidence of your light growing corals? A. The choice of how many white and blue LEDs to use has been tested in our laboratories until the balance that gave the best results with corals was obtained. This test lasted more than a year, with the collaboration of experts in the industry. Q. What about the controller design? A. We designed our lighting system in order to have a large number of LEDs that are supplied with power that is less than nominal current specified by the LED manufacturer. For example, the blue LEDs are operated at 70% of their nominal operating current. This insures the maximum possible lifespan for the unit. To guarantee the best quality control, we calibrate all the power packs coming out of our company one by one to verify that they supply stable output current. Q. Why isn t the sunrise/sunset controller integrated into the unit? A. The sunrise/ sunset controller can be easily connected to or disconnected from the power supply cable. This permits removal of the controller in case of damage, without having to disconnect the light itself, leaving the tank in the dark. Another benefit of this design is that it permits the controller to be upgraded without the need for replacing the entire unit.