UV Light Source General Information & Frequently Asked Questions

Delivery Times
Usually, you will have a unit sitting on your front door step within three weeks anywhere in the contiguous United States for the 11X14, 14X16, and 18X20 sizes.  Shipments overseas take several days more, due to special packaging requirements.  Light sources are shipped UPS Ground.  The shipping boxes are oversize, and it is not recommended to ship the units by air.  The oversize boxes do not fit the automated handling equipment used in air shipments, and consequently the units will get damaged in handling.
 
 
Unit size Unit Weight Shipping Size
11 X 14 25 pounds  30" x 20" x 12" 
14 X 16 30 pounds 30" x 30" x 12" 
18 X 20 55 pounds 36" x 32" x 13" 
20 X 24 85 pounds 60" x 40" x 13" 

The UV light sources are design to set on table tops, and are intended to be kept in one location.  If you have need to move your light source from location to location, such a teaching courses, let us know and we will build you a unit with a special high strength glue.  Also, a wooden crate can build to aid in transporting and protecting your UV light source, if you have the need.

Wooden Shipping Crate is Available to Protect Your UV Light Source

No longer worry about your UV Light Source arriving safely

Crate is lined with 2" foam in the corners, top  & bottom

Ideal for shipping to Workshops, Vacation Home, etc.

Crate can be designed for extra space for timer, print frame, supplies, etc.,

11X14 to 18X20 sizes . . . . . . . . .  $100.00
Other Sizes Available by Quote
 

Power Requirements
11 X 14 8 - 1" diameter tubes 120 VAC - 2.2 Amps - 265 Watts
11 X 14 HO 8 - 1" diameter tubes 120 VAC - 3.3 Amps - 400 Watts
14 X 16 12 - 1" diameter tubes 120 VAC - 3.3 Amps - 400 Watts
14 X 16 HO 12 - 1" diameter tubes 120 VAC - 4.5 Amps - 540 Watts
18 X 20 12 - 1½" diameter tubes 120 VAC - 3.3 Amps - 400 Watts
18 X 20 HO 12 - 1½" diameter tubes 120 VAC - 8.0 Amps - 960 Watts
20 X 24 16 - 1" diameter tubes 120 VAC - 6.4 Amps - 770 Watts
20 X 24 HO 16 - 1½" diameter tubes 120 VAC - 12 Amps - 1440 Watts
40 X 30 22 - 1" diameter tubes 120 VAC - 8.8 Amps - 1100 Watt
30 X 40 HO 22 - 1½" diameter tubes 120 VAC - 16.5 Amps -1980 Watts
Note:  GRA-LAB model 300 timer's are rated at 600 watts at 120 VAC.

If you have a digital timer that will not handle the above wattage for the light source you are interested in, a latching relay can be added to the light source for an additional charge of $75.00.

Use of Print Frame
Units are designed to fit most standard print frames.  All Bostick-Sullivan print frames fit the print format indicated by UV light source format.  For example, their 11X14 frame fits the 11X14 UV light, and the 16X20 print frame fits the 18X20 UV light source.  The door opening for the print frame is 3" high.  The distance from the bottom of the tubes to the negative is optimum so there is no tube shadowing effects.
 
Approximate Inside box dimensions:
11 X14 22" long by 14½" deep
14 X 16 22" long by 19½" deep
18 X 20 28" long by 23½" deep
20 X 24 40" long by 32½" deep
20 X 24 HO 51" long by 33" deep

Special UV box sizes can be built to accommodate any size print or vacuum frame.  Usually an additional two week delivery.  Sometimes there is an additional charge of $25.00 if its more than 2-3" larger.

Exposure Times
Exposure times for the 11X14, 14X16, and 20X24 are approximately 3 minutes for a medium density negative.  The 18X20 uses larger diameter tubes, which are less energy efficient, and takes about 4 minutes and 20 seconds for a medium density negative.  The one (1) inch diameter tubes put out more UV light than the 1½ diameter tubes.  Also, the one inch tubes can be spaced closer together, which will give more UV light per square foot of area.

High Output (HO) Exposure times versus Standard Black Light

Typically, the HO units are twice as fast the the Standard Black lights.  That is to say, the exposure times of the HO units are usually half of the times of the Standard Black lights.
 

Mike K. writes when he compares his 20 watt Black light UV Light Source to his new HO 60 Watt unit:

"I pulled out one of my most popular images.  It is a 10x12 enlarged negative with a density range of 1.92. On the old 20 Watt UV unit w/ 100% palladium I had to print this negative at 360 seconds (6 minutes).  My comparison shows that the new exposure unit with 60w bulbs prints the same negative in 105 seconds vs 360 seconds with the old unit.

One pyro/pmk negative that previously took 10-1/2 minutes printed in 215 seconds (3min 35 seconds).

I no longer have time to coat between sheets or read a book. ;-) "
Mike K.-

Large Cooling Fan for More Consistent Lamp Output.
The light sources are designed with an oversized fan and unique cross-flow air system that incorporates a door.  Open this door and place your print frame under the UV light tubes.  Keep the door closed during exposures.  Air flow is important because the cooling it provides helps keep the light output at a constant intensity.  Constant light output gives much more repeatable exposure times and results.  Fluorescent tube light output drops significantly as the tube's temperature increases; this is why the units have been designed with an oversize fan/fans and the cross-flow air system which incorporates the door.

UV Tube Life
The black light (UV) tubes are rated at 7,500 hours life, while most light bulbs are rated at only 1,000 hours.  You may wish to replace your black light tubes after 2000-3000 hours of use, because there will be about 12% reduction in intensity at these times.   One year of eight hour work days equals 2080 hours; so estimating your total "on" time for an average day and the number of days per year you print will give you a bench mark for when you need to change your tubes.  Two thousand hours would be about 5-10 years use for most photographers who use their light source once or twice a week.   Most lighting supply houses have them or can order them.

They are designated as: F15T8/BL preheat (11X14) or F20T12/BL preheat (18X20 for the standard units).

Replacement bulbs are available from Top Bulb contact Cheryl at 1-800-867-2852 ext 8742. www.topbulb.com

Trade-Up Option - Unsure of what size to buy?
Exclusive Trade-up option for UV lights sources purchased directly from Edwards Engineered Products (proof of original invoice required) allows the beginner to buy the 11X14, and at any time later trade-up for a larger size for the cost difference.  For example, if there is a $155 cost difference between the 11X14 and 14X16, their 11X14 unit will be exchanged for a 14X16 when they send in their 11X14 unit.  The cost of the new 14X16 unit would be the $155 difference.  The person is responsible for sending in their old unit and the shipping charges on the new unit.  What a deal, your light source does not lose its original value!!!

Vacuum Frames Available
Stand alone Vacuum frames are available in just about any size you want.  For light sources with a built-in vacuum frame, the vacuum frame pulls out as a drawer mounted below the light source.  Due to the weight of the drawer, the UV Light Source must be mounted to solid table or counter top with "L" brackets that are provided.  The front edge of the unit must hang over the edge of the table or counter by 2" to provide clearance for the vacuum pump hose to hang down.

The paper and negative are loaded onto the vacuum mat in the open drawer position, the glass frame is closed and vacuum pump is started, then the drawer is pushed in under the light bank for the timed exposure.  These unit's typical delivery is 6-12 weeks, depending on the unit size. Units are usually shipped on a pallet, and special handling maybe required for inside delivery or for stairs if no freight elevator is available.

Operating Instructions
Your light source is warranted for one year and is designed to give you many years of trouble free service.

Before plugging your new light source to a power outlet: Carefully remove any packing between each black light tube and carefully remove the masking tape from each of the tubes. Visually check tubes to make sure they are seated in sockets, with each tube-end pins, horizontal. The tubes may have shifted in shipping so to make sure they are seated properly,  twist the tubes back and forth in the sockets a couple of times, about 90 degrees rotation, and you can feel the tubes seating in the notches of the sockets.  If the unit sits for a while without use, or if the darkroom is unusually damp, sometimes some of tubes will not start.  Just turn the unit over and twist the tubes back and forth in the sockets several times, about 90 degrees rotation, and this is usually enough to clean the corroded contacts for the lamps to start.

The light sources are designed with an oversized fan and unique cross-flow air system that incorporates a door.  Open this door and place your print frame under the UV light tubes.   The distance from your print to the UV tubes has been designed to provide maximum uniform light intensity for optimum exposure levels, and maximum corner to corner consistency.  Place your light source on a white surface, such as a piece of mat or white foam core board, to benefit from the reflected light.  This helps insure your print is exposed with ample UVA and UVB wavelengths of ultraviolet light necessary for the platinum process.  Before your first exposure, it is best to stabilize the temperature by operating the unit for 30 seconds to one (1) minute.  Repeat the warm-up if the unit is off more than 2 hours.

Place light sources in a location with at least 4" clearance on each end (fan and vents end) to provide ample air flow.  Keep the door closed during exposures.  Air flow is important because the cooling it provides helps keep the light output at a constant intensity.  Constant light output will give you much more repeatable exposures times and results.  Fluorescent tube light output drops significantly as the tube temperature's increases; this is why the units have been designed with an oversize fan and the cross-flow air system which incorporates the door.

Plug the unit into an electrical outlet and check the GFIC (Ground Fault Interrupt Circuit outlet) before turning on the switch. Push in the reset button until you feel a click (if it has been tripped and is sticking out slightly).  Test the GFIC weekly by  pushing the test button and resetting with the reset button.  If you can reset with the reset button, then the GFIC will protect you from electrical shock when using your UV light source.

When the fan filter becomes laden with a white-gray powder, unplug your unit from the electrical power source or your timer, and gently pry off the outer plastic cover from the edges.  Note:  the small square slots to pry off the cover.  The cover holds the foam filter in the housing.  Wash foam filter in warm soapy water and rinse.  Wipe the filter cover and housing with a damp cloth.  Thoroughly dry the foam filter before re-installing the filter and cover.  Place foam filter in the housing and push the cover onto fan housing.  Plug unit into electrical outlet and test GFIC and reset with the reset.

Danger:  Do not remove top cover while the unit is connected to a power source like a timer or electrical outlet.  Keep hands and fingers away from the ends of the fluorescent tubes, tube sockets, and the fan(s).

WARNING - DO NOT USE or place your UV light source near pets, fish, infants or small children.  Do not allow children to look at the lights. Protect your eyes (sun glass or lenses with UV blockers, both A & B) and skin from exposure.  The light sources produce SEVERAL TIMES the amount of Ultraviolet Radiation we received ON EARTH from the SUN. Think about it, it hurts to look at the sun and most people cannot look directly at it.  Look at the sun or at arc welding, without protection, and eventually, it is highly likely that you will go blind.  The reason that we see few welders past the age of 50, even when they used the proper shielding and eye protection for UV, is that their eyesight is no longer good enough to weld after looking at the light or flame (which gives off UV) for 25 or so years.  The same applies to your UV light source. Looking at the UV light source is equivalent to standing beside someone arc welding, and you watching the arc without any eye protection.

PROTECT YOUR EYES FROM UV EXPOSURE DURING THE USE OF YOUR LIGHT SOURCE.

Caution: High Intensity UV Radiation
1.  This Light Source emits ultraviolet (UV) Radiation during operation.
      It is in Risk Group 2 per ANSI-IESNA  RP-27.3-96.
        *  Exposure at less than 0.75 meters (30 inches) should be limited:
        *  Exposure at 0.55 meters (22 inches) should NOT exceed 4 hours in any 8 hour time interval.
                *  See ANSI-IESNA RP-27.1-96.

2.  Certain Medications and Chemicals can increase an individual's sensitivity to UV Radiation.
        Consult your physician for specific information.

3.  Protective eye wear and clothing should be worn at all times involving long-term exposure in close  proximity to the lamps.

4.  These Lamps and Light Source are not intended and should not be used for diagnostic, therapeutic, or cosmetic purposes.

The following companies have safety glass that block 100% of UV light as defined by
ANSI standard, ANSI Z87.1-1989.
 
Lab Safety Supply 1-800-356-0783
Fisher  1-800-766-7000
Cole-Palmer 1-800-323-4340

 
 
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