Answer / karthik

The starter is basically a time delay switch. Its job is to
let the current flow through to the electrodes at each end
of the tube, causing the filaments to heat up and create a
cloud of electrons inside the tube. The starter then opens
after a second or two. The voltage across the tube allows a
stream of electrons to flow across the tube and ionize the
mercury vapor.
Without the starter, a steady stream of electrons is never
created between the two filaments, and the lamp flickers.

Answer / bhanu pratap

Tube light requires two things to function . Very high starting voltage , and high voltage to continue the operation . The starter is a circuit which breaks at regular intervals . When you break a circuit and start again , high voltage spark takes place . This voltage is further amplified through the choke which is a transformer . Thus at the beginning the starter gives high voltage sparks . Due to this the current begins to flow through the tube and the tube begins to glow. Once the tube starts , the required voltage to sustain is quite low , which is provided by the choke .

If the starter is bad the tube does not start . If the choke is bad or if the gas is low , the tube does not sustain its light .

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