180704-2401 EDT


The article may suggest that inductive kick starts the lamp arc when the starter contact opens, and there may be such a kick. But I would not agree that this is of any importance.

What is important is that the filaments are hot and thus electron emitters, and that there is sufficient supply voltage to cause arc conduction in the fluorescent tube. This has to and does reoccur every 1/2 cycle. You can see a high initial voltage drop across the tube that drops substantially as current increases thru the half cycle. When voltage drops below holding voltage then the arc stops. On the next half cycle the cathode shifts to the other end of the tube, and a new arc has to be started. After this initial heating, and on a continuing basis this all occurs with no opening and closing of the starter.

The purpose of the starter is to initially heat the filaments so that they are good emitters of electrons. Current thru the heaters to support the arc keeps the heaters hot from cycle to cycle after the filaments have been initially heated, and the heater thermal time constant is long enough that too much cooling does not occur from cycle to cycle.