Replies

1. 
   Bill_Hartmann | Dec 18, 2001 09:43pm | #1

   *
   Try different styles of bulbs. Try the very long life bulbs. They are basically the same as the 130 volt bulbs.

   Or try the rough service bulbs.

1. 
   xJohn_Sprung | Dec 19, 2001 12:26am | #2

   *It's the rough service bulbs that work for this. Dimmers work by turning off at the zero crossing of the 60 Hz power, and then waiting for some delay period and abruptly turning all the way on to re-join the gentle sine wave. Most of them have choke coils in series with them to smooth this out a little, but the rate of change of current at that point is still very large, which means that the coiled wire of an ordinary bulb's filament gets a strong hit of electromagnetism, which causes it to constrict on itself, then release like a spring. This translates into vibration. The higher rated dimmer has a bigger choke, which is why the upgrade has worked for you in the past. The rough service filaments are in big loose loops rather than tight coils, so they get whacked much less by the electromagnetism. And, being rough service, they stand up better to what little vibration there is.-- J.S.

1. 
   Dave_Richeson | Dec 19, 2001 02:53am | #3

   *John, you just saved me an hour or two of research. I am going to box my reference books back up. You da man!

1. 
   4Lorn | Dec 25, 2001 07:54am | #4

   *Those 130v lamps, bulbs, should be available from an electrical supply house, any of the better home centers or Graingers. They are sometimes listed as commercial or heavy duty. They burn a bit less bright but last considerably longer. This can help in difficult to get to fixtures or districts with poor voltage control, spikes or surges.

1. 
   John_Steinke | Jan 23, 2002 04:28am | #5

   *Try a better, electronic dimmer. Or, try one that has speeds set in "steps," rather than being infinitely variable. In either case, select one intended for it's use (motor, lights, etc.)