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Retr0Bright: How do I know if my UV bulb is working?

LC_575

Well-known member
I just bought a set of 4 UV bulbs for a nail dryer machine. However, each bulb shares the same socket mount as a CFL desk lamp I own. It works with it's standard 13W florescent bulb. Each UV bulb is a 9W bulb, and fits in the desk lamp perfectly. However, when I turn the lamp on (w/ the UV bulb installed), it appears that the bulbs (all four) don't work. No clicking of the bulb heating up, no light, no sensory indication of successful operation. Now I know UV bulbs don't put out much light, but even in a perfectly dark room the bulb produces no light. What's going on? Do I have a bad batch of bulbs or is my lamp not appropriate for the task?

Also, do these bulbs take more than a minute to heat up? I've only left mine on for no more than 10 seconds.

 

Anonymous Freak

Well-known member
Find out what kind of socket the UV bulbs are actually meant for. It might be that the physical socket is the same, but has different electrical properties.

For example, does your CFL have its own ballast, or is it "just tube"? If it's just a tube, with no ballast (the bulky electronic part of a CFL that uses a standard socket,) then the CFL is likely expecting fairly high incoming voltage (Fluorescent lamps require fairly high voltage, so desk-type CFLs use a step-up transformer internally.) They also use DC rather than AC. If your UV bulb is a standard incandescent UV, then it is expecting mains voltage, AC. You might very well have blown the bulb; although if you didn't hear/see anything, that's not too likely.

 

redrouteone

Well-known member
Also you could turn the lights out and stick a sock under the lamp. The phosphorus left behind from the detergent fluoresces in the presence of UV light.

 
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