Causes : Loose fixtures,ballast mounting loose,defective ballast
Symptom: lamp discolored ,dark bands near ends
Causes : Defective starter, defective ballast , end of lam mercury accumulation (gray streaks on lower port of tube, rotate lamp tube to correct)
Symptom : lamp blinks
Causes : lamp failure (end of life if lamp balckened ), defective starter (especially a new lamp has been installed) defective lamp, low input voltage , low ambient temperature
Symptom: only lamp ends light
Causes : Defective starter
Symptom : short lamp life
Causes : input voltage too high or too low, poor contact in lamp sockets,switch on/off too often
