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ReNae Stueve · 07-11-2004, 07:42 PM

RE: Humming Ballasts. There are several types of Ballasts on the market, each designed to operate different lamps. If you have a fixture that takes F32T8 Lamps of any spec, you have a lamp that is 1" in diameter and designed to be pushed by an electronic ballast. This is the most current commercially used set up and should not produce any hum, but harmonic distortion is an issue, however not if you have a single 4 lamp fixture on the line.

The F34T12 RS lamps, at 1-1/2" diameter, are pushed by an electro-magnetic ballast, and these ballasts can make a nasty noise.

These are both called Rapid Start. Look for the RS on your lamp logo. No starter is needed. The starters are still used today in lamps 24" long and under, in any tube diameter.

The problem with the Home Depot style fixtures is that even though the ballasts and lamps are labeled GE or Sylvania, they are mass produced "B" quality for home use, typically garage lighting where hum and VCP, CRI are not an issue.

If you have a commercial electrical supply house in your area, ask if they have the GE UltraMax Ballast and SPX series lamps. This combination all but eliminates hum, distortion and the terrible eye fatigue you will get from residential brands because they have included a very effective Striation Control with this combination.

Try, Graybar.com or search Lithonia Lighting or Genlyte-Lightolier for store locator's.

07-11-2004, 07:42 PM	#35
ReNae Stueve Associate Member Joined: Dec 2001 Location: Kapolei, HI Posts: 171	T12 vs T8 RE: Humming Ballasts. There are several types of Ballasts on the market, each designed to operate different lamps. If you have a fixture that takes F32T8 Lamps of any spec, you have a lamp that is 1" in diameter and designed to be pushed by an electronic ballast. This is the most current commercially used set up and should not produce any hum, but harmonic distortion is an issue, however not if you have a single 4 lamp fixture on the line. The F34T12 RS lamps, at 1-1/2" diameter, are pushed by an electro-magnetic ballast, and these ballasts can make a nasty noise. These are both called Rapid Start. Look for the RS on your lamp logo. No starter is needed. The starters are still used today in lamps 24" long and under, in any tube diameter. The problem with the Home Depot style fixtures is that even though the ballasts and lamps are labeled GE or Sylvania, they are mass produced "B" quality for home use, typically garage lighting where hum and VCP, CRI are not an issue. If you have a commercial electrical supply house in your area, ask if they have the GE UltraMax Ballast and SPX series lamps. This combination all but eliminates hum, distortion and the terrible eye fatigue you will get from residential brands because they have included a very effective Striation Control with this combination. Try, Graybar.com or search Lithonia Lighting or Genlyte-Lightolier for store locator's. __________________ ALWAYS REMEMBER Life is not measured by the number of breaths we take, but by the moments that take our breath away.