jbm@eos.UUCP (Jeffrey Mulligan) (09/26/89)
I friend recently loaned me an unused mercury vapor lamp from his greenhouse, and when I powered it up, I fried the bulb. Before I go out and buy another one I wanted to find out if there might be another problem besides an old and possibly flaky bulb. I opened up the power supply box, and all it had inside were a BIG transformer (putting out about 240 vac), with a BIG cap (24uF, 500V) in series with the output. Why is this cap there? Current limit protection to keep the transformer from burning up? (There was also a 1/2 watt resister across the cap terminals, which I presumed was to discharge it after a power down.) The box from the lamp mentioned a "ballast resistor;" I am worried that perhaps the bulb fried because I didn't have one. At the time I assumed this component was internal to the power supply. Any and all help will be appreciated. jeff -- Jeff Mulligan (jbm@aurora.arc.nasa.gov) NASA/Ames Research Ctr., Mail Stop 239-3, Moffet Field CA, 94035 (415) 694-3745