8 foot flurescent lamp

Question

Hi guys and girls firstly to days my birthday I've got to 58 years old never thought ide make it especially with all the health issues I've had over recent times any way now to be serious can someone please show me the wiring diagrame for an 8 foot flurescent light single tube I'm curiouse how it's wired especially the capacitor position I know they have one in series but not sure if it's exact circuit position thanks in advance x

mapj1 · Accepted Answer

there are a couple of versions - first the simplest series choke an starter, just like a 4ft tube, herer the cap is just accross the mains as a power factor correction, a sort of impedance match between the 230V mains and the 150 or so of the tube once struck. 
 Better, especially in cold weather, were the ones with the ballast more like a tapped transformer, so the heaters had their own windings. and the strike voltage was a bit higher. Again cap for PFC. 
 Then there were resonant starters, where the cap has to be matched to the series choke and tune to 50Hz - here the cap goes where the starter would. and as the series resonance builds, the voltage on the tube rises, as does the filament current, until something strikes, or the filaments blow open cct. Very fast to strike, but needed cap and choke to be a matched pair and no good on gensets with poor frequency control. 
 Mike

broadgage · Answer

In my youth, we had a similar problem with a number of 8 foot fluorescent lamps in cold weather and low supply voltage. 
 I fitted a 30 volt transformer, wired as an auto-transformer to increase the supply voltage by about 27* volts, so with an actual measured voltage of 210 volts, the lights received 237 volts and worked much better. To avoid overstressing the lamps and ballasts, I fitted a changeover switch so as to supply straight mains, or mains plus 27 volts. The two switch positions were marked "summer" and "winter" Worked for years ! 
 * The transformer was ratted to supply 30 volts with a full 240 volts input, used on the reduced mains voltage the output was reduced in proportion to about 27 volts.

8 foot flurescent lamp

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