Be sure to use the proper lamp for a given ballast. Mismatching a lamp and ballast may result in poor starting and poor performance, as well as shortened lamp and/or ballast life.

The manufacturer’s ballast and/or lamp warranty may be null and void. T8 lamps are designed to be used interchangeably on magnetic or electronic rapid-start ballasts or electronic instant-start ballasts. Lamp life is reduced slightly when used with an instant-start ballast.

Operating a ballast at an over-voltage condition will cause the it to run hot and shorten its life. Operating a ballast at an under-voltage situation can result in premature lamp failure and unreliable

Most ballasts today will operate satisfactorily within a range of 15% to 27% of their rated voltage. The higher quality CBM certified ballasts will operate satisfactorily within a range of 610%.

Ballast Sound Rating
Most ballasts will hum, some more than others. Ballasts are sound rated and are marked with letters “A” through “F.” “A” is the quietest, and “F” is the noisiest. Look for an “A” or “B” sound rating for residential applications.

Magnetic ballasts (core and coil) hum when the metal laminations vibrate because of the alternating current reversals. This hum can be magnified by the luminaire itself, and/or the surface the luminaire is mounted on. Electronic ballasts have little, if any, hum.

CAUTION: Do not insert spacers, washers, or shims between a ballast and the luminaire to make the ballast more quiet. This will cause the ballast to run much hotter and could result in shortened ballast life and possible fire hazard.

Instead, replace the noisy ballast with a quiet, sound-rated one. Sometimes checking and tightening the many nuts, bolts, and screws of the luminaire will solve the problem.


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