F96T12 DD VHO
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Just chilling I guess
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I was really thinking about this since I see the hot lead and the neutral lead and the filament is in the middle?
Am I over thinking it or is it really simple? Or am I just wrong?
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Lumex120
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/X rated
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I was really thinking about this since I see the hot lead and the neutral lead and the filament is in the middle?
Am I over thinking it or is it really simple? Or am I just wrong?
It's just a resistive load, so no. Incandescent bulbs are just small heaters.
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dor123
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Other loves are printers/scanners/copiers, A/Cs
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Discharge lamps such as fluorescent lamps and HID lamps, are short circuit when operated without a ballast, as the discharge don't limit the current by itself like the filament does.
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I"m don't speak English well, and rely on online translating to write in this site. Please forgive me if my choice of my words looks like offensive, while that isn't my intention.
I only working with the international date format (dd.mm.yyyy).
I lives in Israel, which is a 220-240V, 50hz country.
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lightinglover8902
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Power distributor: CenterPoint Energy. 120V 60Hz
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An incandscent light bulb has a filament resistive wire that glows and heats up when a electrical current is applied. The same thing that goes with halogen lamps, they do also have a filament resistive wire. Which depends on the halogen lamp size.
So, incandscent and halogen lamps are only resistive loads.
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Save the Cooper OVWs!! Don't them down by crap LED fixtures!!!
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F96T12 DD VHO
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Just chilling I guess
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I do use them as space heaters
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F96T12 DD VHO
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Ok thanks, this was making me wonder
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Ash
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You were not far off however. The relatively thick filament of low voltage Halogen lamps is, in fact, nearly short circuit when cold (so when the voltage is first applied). Only when it heats up, it builds up the resistance. So such lamps draw a big current spike when switched on. This happens but to lower extent with higher voltage Halogens, and to even lower extent with ordinary Incandescents
Also, many electronic ballasts present a momentary near-short circuit when switched on, that is caused by the input filtering capacitance that have to charge up in very short time
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589
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Tha SOX MADMANNN
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You were not far off however. The relatively thick filament of low voltage Halogen lamps is, in fact, nearly short circuit when cold (so when the voltage is first applied). Only when it heats up, it builds up the resistance. So such lamps draw a big current spike when switched on. This happens but to lower extent with higher voltage Halogens, and to even lower extent with ordinary Incandescents
Also, many electronic ballasts present a momentary near-short circuit when switched on, that is caused by the input filtering capacitance that have to charge up in very short time
Would inrush current limiting be a secondary reason 12v halogens have a transformer then?
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Ash
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It helps to some extent (the leakage impedance of the transformer is in series with the load, so limiting the short circuit current, yet it does not have as significant effect when in running mode), but hey, in cars the transformer is not needed to step the voltage, and it seems that there is no problem without it (such as welding relay contacts by the high current) ?
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589
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Tha SOX MADMANNN
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Thanks for the clarification. That's what I was thinking along the lines of the transformers use.
In my years I've spent in the car repair business I have not come across stuck relay contacts yet. Most vehicles I've come across actuate the lighting system via switch or solid state means therefore reducing the possibility of stuck contacts. I have seen burnt up headlight switches though. The only relay consistently that I have found especially in older vehicles is the turn signal flasher. They occasionally do fail closed.
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