Philips Electromagnetic Lamp manual 114, Starter types

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2.2 Starter types

Fig. 106. Working principle of a glow- discharge starter circuit.

1.The heat from the discharge in the starter bulb causes the bimetallic electrodes to bend together.

2.When the bimetallic electrodes make contact, a current starts to flow through the circuit, sufficient for preheating the electrodes of the fluorescent lamp.

3.The bimetallic electrodes cool down and open again, causing a voltage peak, which ignites the fluorescent lamp.

starting process again until the lamp ignites. If the lamp will not ignite (end of life) the starter will continue producing peaks (flickering) until the mains voltage is switched off or until the electrodes of the glow- switch starter stick together. In the latter case the short-circuit current is continuously running through the lamp electrodes, which can be seen at the glowing lamp ends.

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Once the lamp is properly ignited, the lamp voltage is too low for a glow discharge between the starter electrodes. So these electrodes stay ‘cool’ and in open position.

A capacitor across the starter electrodes prevents radio-interference of the lamp.

There are five types of glow-switch starters, specified for a certain mains voltage and/or lamp wattage ( S2-10-11-12-16).There are also resettable glow-switch starters: SiS2, Si S3 and SiS10.These starters switch off after a certaintime in case the lamps do not ignite and have to be reset manually by a push button. Switching the mains supply does not reactivate a switched-off resettable starter.

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