UV Display LampsCaution: As with any mid-wave or short-wave ultraviolet source, you must not allow anyone to look into the light or shine it on bare skin as it will cause damage to the eyes and/or sunburn to any exposed skin.
Although we take our big lamps in the field, the display lamps are primarily intended for inside conditions. These high-powered ultraviolet display units will light up your fluorescent collection for an awesome exhibit. The units are available in long-wave, mid-wave, and short-wave ultraviolet models as well as combinations of the various wavelengths.
We currently make models from 9 watts to 190 watts. The bigger units operate on 110 volt AC, 60 Hertz power, but I can custom make them to operate on 230 volt AC, 50 Hertz as well. For 230 volt AC, please allow a few weeks extra for manufacturing because I do not keep all of the necessary parts here in stock. The standard display units are made in a metal fixture with a black powder coat finish, stainless steel lids and a black plastic handle. The metal boxes come in 4 basic sizes - small 3" x3" x15" (7.62cm x7.62cm x38.1cm), medium 4" x4" x18" (10.16cm x10.16cm x45.72cm), large 4" x8" x18" (10.16cm x20.32cm x45.72cm), and extra-large 4" x5" x24" (10.16cm x12.7cm x60.96cm). As special orders, I can make the display units out of oak or Baltic Birch plywood. When working with the wooden boxes, I can resize many of the dimensions to fit your needs. I currently offer the smaller units in 12 volt DC versions or 110 volt AC versions. The enclosures for my line of 9 watt lamps are black ABS project boxes. They come in two sizes 2.5" x4" x7.5" (6.35cm x 10.16cm x19.05cm) and 3" x6"x8" (7.62cm x 15.74cm x20.32cm).
Models of Lamps
36 watt units and 60 watt units
I no longer make a 25 watt unit. The size of the box and the filter are the same for 25 watt bulbs, 36 watt bulbs and 60 watt bulbs. Since the 36 watt bulbs are so much stronger than the 25 watt ones, it does not make sense to me to make a 25 watt unit. These units all use the 4"x4"x18" box. The standard unit is set up for 110 volt AC, 60 Hertz power, but I can make these units with 230 volt AC, 50 hertz power.
95 watt and 190 watt SW Units
The 190 watt unit has two of the 95 watt bulbs and the filterglass is 4"x19 5/8". Philips rates the bulb at 32 watts of UVC at 100 hours of use. For comparison, a Philips 25 watt SW bulb emits 7 watts of UV C. These units require a fan to cool the bulb. 190 watt SW units.
BallastsA few years ago, I switched over to hi-efficiency, electronic ballasts for all of my larger AC lamps. The electronic ballasts cost quite a bit more than the magnetic ballasts, but they give off more light and they do not wear out the bulbs as fast as the magnetic ballasts. The smaller 9 watt (see description below) AC units do still use magnetic ballasts. Futher, in both the AC and DC versions, I am using 13 watt ballasts to drive the 9 watt bulbs. The SW bulbs are rated by Philips to have an average life of about 10,000 hours. Using a stronger ballast greatly increases the amount of UV that is emitted by the bulb, but it does shorten the life of the bulb somewhat. The 9 watt PL-S bulbs, have capacitors built into the base of the bulb to allow them work properly with the magnetic ballasts. The DC lamps use a different kind of ballast and the capacitor is not needed, so I take the capacitor out of the base of the bulbs used in the DC lamps. The reflectors are made from highly polished aluminum. The short-wave (UV-C) and mid-wave (UV-B) models feature Hoya filter glass (U-325) for the very best in ultraviolet transmission and resistance to solarization.
9 Watt Field and Small Display Units
These units come in attractive black ABS enclosures with a black plastic handle. They are lightweight and are very comfortable to hold. The bulbs are available in SW, MW and LW and I make units with single bulbs, two bulbs and also all three wavelengths. For people on a very limited budget, the most cost effective way is to buy one unit and the extra bulbs to convert it from one wavelength to another. The dual and triple bulb units are approximately 6" x 8" x 3" with the handle sticking up an additional 2.5". The single bulb units are a little smaller. Each wavelength has it's own switch and any combination of the bulbs may be on at the same time. I offer 9 watt models in both 110 volt AC and 12 volt DC versions. The DC versions do not have an internal battery. They come with a male cigarette plug on the power cord to plug into any standard battery pack. The 12 volt ballasts are custom manufactured and they were designed to "overdrive" the bulb as if it were a 13 watt bulb. This does shorten the life of the bulb a little, but the original rating is for 10,000 hours of use. I felt that the increase in UV output was worth the slightly shorter life of the bulb. This only applies to the DC models.
*** Special Bulbs ***One very strong selling point for the Philips bulbs that I use, is that they put out more UV over the life of the bulb than the standard quartz bulbs and they also have much less mercury in them. Philips also uses a different kind of glass so that none of the ozone producing UV gets emitted from the bulb. Most of the standard quartz bulbs do produce ozone. Philips figured out that part of the reason that the standard quartz bulbs lose efficiency is that the mercury gets into the structure of the quartz and changes it so that less UV gets through. Because the mercury absorbs into the glass, the standard quartz bulbs have to put in about 5 times as much mercury, so that there will be enough mercury left at the end of the useful life of the bulb. Philips found that putting a coating of yittrium oxide on the inside of the bulb helps to stop the mercury from getting into the glass. This coating allows the bulb to emit much more UV over the life of the bulb. Tests have shown that at 10,000 hours, the quartz bulbs are emitting only about 53% of the UV that they did when the bulbs were new. The Philips bulbs, on the other hand still emit about 80% of the UV that they started out with. The quartz bulbs do start out with a little more at the beginning since the quartz glass allows about 92% of the UV through, while the boro-silicate glass only allows about 88% of the UV through. The cross over point where the Philips bulb starts outperforming the quartz bulbs is about 2,000 hours, so for the rest of the 8,000 hours of typical use, the Philips bulb produces much more UV than the quartz bulbs.
UL ListingNone of my lamps are UL listed at this time because that process is very expensive and out of my price range to make happen. The UL Listing costs about $6,000 for each model of lamp. However, there is another way to meet the requirement. The UL Listing only applies to the part that plugs into the 110 volt AC. If a UL Listed 12 volt power supply provides the power for the big display lamp, the whole unit meets the UL requirement. I am told that the Fire Marshals at the big shows are requiring display lamps to be UL Listed. These DC units should satisfy the Fire Marshal as long as the power supply is UL Listed. I am in the process of making some 36 watt display units (and probably the 60 watt unit also) in 12 volt DC versions. The 12 volt versions are a little more expensive because of the inverter ballasts and also because of the power supply. In addition to making my line of DC display lamps, I am looking into the possibility of offering to convert other types of lamps to DC. If you think you would like to convert some of your lamps to DC, please e-mail me to discuss it. I won't offer the service if there is no interest in it.