Can't speak for anyone else, but I built one of the Ubuild It UV boxes using the Workhorse 7 electric ballast and have 12 T12 BLB bulbs. They all come on pretty much all at once....ie no delay at all. Why not just turn the unit on first and then slide the contact print frame in? Probably makes no difference, just wondering since I do it that way with no issues. BTW, you are correct about the spacing, mine are right at 5/16 of inch apart and it is a tight fit to change blubs...good news is should not have to do it that often. The print frame is right at 2 1/2 inches from the bottom of the blubs, and have printed 4x5 - 8x10 (did one pair of 4x5's, kind of a poor mans 4x10) and have had no issues with light fall off.
That said, if I had room I still would have gone with the 48 inch blubs because they are easier to find, and at least the same price (if not less) than the 24 inch blubs.
Voltage in Sweden is 220-240 V and 50 Hz. Buying US ballasts etc is probably a bad idea.
Reading through these relpies I realise that the qoute I got from the dealer was based on a whole strip, with housing, bipin holders and ballasts. Since I won't use the housing and the ballast, that's definetely a money waster. I should be able to find just the bipin holders and separate ballasts.
I might go with the 20 watt tubes instead. The ballasts are much cheaper as are the tubes.
The screw-in tubes might be an option, I have found 15 watt BLB bulbs for approx 11 USD each, incl VAT. But 15 watts might be too little?
The mercury vapor HID lamps are not an option. Firstly they are not easy to find here. Second, they use a lot of energy, and I would like to keep that as low as possible, considering the well-being of our environment. The ones I've found here are 125 watt bulbs, and I'll need several of those to get enough light. I have seen the 1000 watt versions, but not in screw in. They needed a special connector, special cooling etc, and I felt it was a hassle to mess with. Also, they need a lot of space that I don't have in my darkroom.
I'll call another reatailer to see if they have just the bipins, ballasts and tubes.
A strange thing is that I can't find 40 watt electronic ballasts, only 36 watt. Philips told me that 36 watt ballasts won't work with 40 watt tubes. Are they full of it?
The marketing situation in Sweeden may be different from what it is in the US, but here it is actually less expensive to buy the two tube units intact, with holders, ballast and holders, than to buy the individual parts. The two-tube 48" fixtures are very inexpensive in the US because they are widely used in residential and commercial installations. You have to swap whatever tubes come with the units for UV tubes, but you may be able to buy the units without the tubes, or get credit for them in a swap out. The metal of the fixtures adds a little extra weight, but it eliminates the metal backing plate that you would otherwise need so for good grounding all you need to do is tie the ground together, and of course make sure that your house wiring has a grounding circuit.
Originally Posted by timeUnit
Originally Posted by timeUnit
You are unlikely to find 240 volt 50 hz units in the US. The common voltage in addition to 120 60 hz is 277 volt 60 hz (one leg of 480 volt 3 phase and neutral).
Your Philips representative is correct in his statement about ballasts. They must be specifically matched to the lamps that they are firing.
Lighting manufacturers are normally not involved in the ballast manufacture. These are usually separate companies. However, Philips probably could direct you to a manufacturer.
It is unlikely that you will find anyone here in the US that can supply you a UV exposure unit since they are dealing with the reverse of your situation insofar as parts availability.
A 240 volt 60 hz device here in the US could probably work with 50 hz supply in purely resistive lighting for you since it does not represent an inductive load.
Do you have any companies that supply aquariums? They would have high actinic light supplies for their salt water aquariums.
The other thing that you could do is to incorporate a step down transformer into your supply side of a 120 VAC device. If you decide to do that then you will need to size the transformer for the load that your device represents.
Step down transformers are sized on VA. This represents the volts times amps load. If you for instance had six of the 36 watt lamps that would be 216 watts divided by the load voltage would be 1.8 amps. Thus a 216VA step down transformer would theoretically carry the load. However factoring in the ballast loss and a safety factor, I would opt for a 1000VA transformer. If you decide to go this way be sure and insert a 4 amp inline fuse into the secondary of the transformer to protect the transformer in event of a downstream overload.
Yes, I checked my data sheets and I meant to say MERCURY VAPOR. That said, I still use an ordinary sunlamp. Others use reflector spots (#2 photoflood precisely) and one has a fancy-schmancy Theimer Violux UV lamp. He claims it puts out 3000 watts for a 16 on his meter.
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Sunlamps are efficient for alternative printing. Just remember that the UV radiation they put out is a hazard, especially for your eyes, so when exposing try to do so with some type of curtain around the light, or use UV goggles. They are no longer commonly available on the market precisely because of the hazard factor.
Originally Posted by Poptart
I see them all the time at thrift stores; are there any in Sweden?
I use a 300 watt sunlamp called "Ultra Vitalux" from Osram, right now. I find that it's not powerful enough and the light lacks uniformity -- it's much more powerful in the center than off center. Works OK or really small prints, but the bigger ones are a bust. Last time I used it I exposed a cyanotype for 46 minutes, and it still wasn't close to enough in the edges, so I need a better light source. The lamp is three years old now, but hasn't been used so many hours, still it might be to old to work OK. Anyway the lamp retails at about 80 USD, and I need maybe four for a 8x10 print, plus a powerful fan and housing. It would be a unit that uses 1200 watts, which seems like overkill to me. Sunlamp and HID are out I think.
The Actinic 05 tubes are at 20 and 40 watts, so any "regular" ballasts that would come with a complete fixture would be useless as they are 18 or 36 watts. Also, I have not found any fixtures for 24 inch tubes that are cheap, they are around 80 USD for a 2 tube fixture.
I spoke to a retailer yesterday and she will call me back with a quote for tube, holder (G13 socket), ballast, etc. She understood what I'm trying to build, I think... I think I'll go for 20 watt, 24 inch, "T36" tubes, that is 36 mm diameter (1,5 inch). She claims that those tubes work with 18 watt ballasts, but we'll see. Mr Miller here says otherwise... I'll try the tubes w/ ballasts and everything before leaving the store.
I've seen Actinic tubes at a big pet shop, but I was unsure if they were good enough for these puposes. I didn't even check the price. Also, they were the small diameter kind (18 mm) so I need more tubes for the same width.
I never thought this would be so difficult! Here (APUG) and on Unblinkingeye it seemed quite simple, but the small market in Sweden has really made this quite a task. Luckily I'm not in a hurry.
1) Always match ballast to lamp type. There are different types of 40 W lamps for example that have completely different electrical properties (voltage and current). The lamp voltage and current specs are hard to find, generally only available to ballast designers. This makes some lamps of same wattage and different shape very incompatible. Lamp and ballast life are at risk by using unmatched combinations. In some cases more dangerous problems may develop. Having same length, wattage or connector means nothing. Electrically they are very strange animals when they light. (Negative resistance plasma, etc).
2) I have been interested in trying a type of marine high actinic with most output at 420 nm because the graded papers I could find data one have peak response about 425 nm...I probably am luck to even read the graphs that closely. There are many different spectral variations in marine lamps for different types of plant and animal growth/health. Some have broad spectra, some a couple peaks.
Since I am not in a position to do alt process yet (it takes me forever to research before I do anything, space time, money, etc, etc).
I have never seen any followup as to whether anyone tried those lamps. I may be my own guineapig...most people sensibly don't try to reinvent wheels and do what others have success with.