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Lanterns/Fixtures => Videos => Topic started by: elektro666tech on September 21, 2010, 02:54:11 PM

Title: What should we do with T8 fluorescent tubes :D
Post by: elektro666tech on September 21, 2010, 02:54:11 PM
Hello everyone :)
In this topic I'll show you a few videos showing us what should we do with these horrible, thin T8 fluorescent tubes. I really hate them, cause they replaced T12 fluorescent tubes, and they look stupid in classic fixtures.

http://www.youtube.com/watch?v=oInioyv1xKc

http://www.youtube.com/watch?v=mFbFBYWXKSM

http://www.youtube.com/watch?v=dCU71BL1sFk

Enjoy :D
Sorry for my english.
Title: Re: What should we do with T8 fluorescent tubes :D
Post by: Jace the Gull on September 22, 2010, 05:34:39 PM
Your English is very good! I have seen worse....after working and being a member in LG and GoL....and I noticed this pages also helps others improve their English!

Anyway nice videos! Pretty funny I say...but hey at least your 36 watt T8s still gets preheaters in Europe.....we don't have preheaters for any lamps over 2 feet anymore!
Title: Re: What should we do with T8 fluorescent tubes :D
Post by: elektro666tech on September 23, 2010, 01:58:58 PM
Your English is very good! I have seen worse....after working and being a member in LG and GoL....and I noticed this pages also helps others improve their English!

Anyway nice videos! Pretty funny I say...but hey at least your 36 watt T8s still gets preheaters in Europe.....we don't have preheaters for any lamps over 2 feet anymore!

Preheaters ? Do you think about starters ?
If yes, I'm surprised, that 36W T8 is able to start without starter ::)
Title: Re: What should we do with T8 fluorescent tubes :D
Post by: Medved on September 26, 2010, 01:34:54 AM
Preheaters ? Do you think about starters ?
If yes, I'm surprised, that 36W T8 is able to start without starter ::)

Starter is not a magic: It's only a device (voltage controlled timed switch; with limited life, so need to be replaceable), what ensure the combination of electrode temperature and peak voltage is present for the ignition.
The "preheat" circuit ensure it by first closing starter contacts,preheating electrodes and then create the HV pulse be the contact opening.
In Europe the preheat concept allow the use of simple series choke as a ballast, what is not as heavy, reliable, nice to the lamp (low crest factor) and has quite low losses (mainly, because the total VA's the winding has to serve is quite low - for F36T8 it is only ~90VA), so that's why it is virtually the only concept used for virtually all lamps in 230V areas.

If the ballast ensure same conditions by another means, the starter is then not used:
- Instant start uses OCV so high, the lamp ignite even with cold electrodes. But this high OCV would mean, then the transformer is necessary (~700V for F36T8), so the total winding VA's to handle would be (again for F36T8) about 400VA, so it would be about 4x bigger and 4x more lossy then the series choke, what is the major reason for it not being used. Moreover it has low cyclic life, as it start the discharge at cold electrodes. Used only where only 2-terminal lamps were necessary (explosion proof sockets - making them for more then one contact per each side was difficult)

- Rapid start heat filaments by low voltage supply, what heat them up, so the OCV for the lamp to start does not have to be so high, ~400V suffice for F36T8, what yield to lower total VA's then the instant start, but still quite high, or it has to use mainly capacitor to ballast the lamp, what has high crest factor, so stress electrodes. It has been used in the form of a "resonant - start", where it used resonance to boost up the voltage (note, then this concept is the base operating principle of all HF electronic ballasts used today).
Beside this it is quite complex circuit, what in the view of higher losses, necessity to use 4-pin lamps and generally poor starting reliability mean it has no real advantage for 230V area.

Title: Re: What should we do with T8 fluorescent tubes :D
Post by: elektro666tech on October 04, 2010, 04:53:06 PM
I think that it is not good, that T8 will replace T12 tubes :(
T12 tubes are much more better in many applications, and they looks much more better in classic fixtures. T12 starts faster, and easier than T8, especially in low temperatures.
Title: Re: What should we do with T8 fluorescent tubes :D
Post by: dor123 on January 16, 2011, 07:08:32 AM
T8s (except 15W 30W and 50W) have higher ignition voltage then T12, because they have different buffer gas: krypton. They have also an addition of argon to lower their starting voltage, but it is still higher, then T12s that uses pure argon.
So they can't be operated on existing rapidstarts for T12s, but they can be operated on existing switch start/preheat magnetic ballasts.
T8s have the same lifetime as the T12s but have less wattage then T12.
However modern fluorescent lamps have thicker electrodes, so lamp EOL commonly results in a dead glow starter with may results in infinity preheating or 50hz flickering, so the glow starter should be replaced with the lamp.
Title: Re: What should we do with T8 fluorescent tubes :D
Post by: gailgrove on January 31, 2011, 12:39:00 PM
I can't see the first two videos, they are marked private, and how exactly is throwing a lamp against a brick wall in any way helpful ???  :-\
Title: Re: What should we do with T8 fluorescent tubes :D
Post by: joe_347V on January 31, 2011, 10:04:55 PM
I don't like the electronic instant start ballasts that T8s are often paired with rather then the lamps themselves. I would like them much more if they were ran on T8 magnetic rapid start ballasts, preheat ballasts or to a lesser extent even the programmed start ballasts.
Title: Re: What should we do with T8 fluorescent tubes :D
Post by: dor123 on February 04, 2011, 05:08:40 AM
I can't see the first two videos, they are marked private, and how exactly is throwing a lamp against a brick wall in any way helpful ???  :-\
@gailgrove: You are right. When i trying to enter the two first videos, Youtube forces me to sign in.
Title: Re: What should we do with T8 fluorescent tubes :D
Post by: gailgrove on February 04, 2011, 06:43:39 PM
I did sign in but it still didn't work :-\
Title: Re: What should we do with T8 fluorescent tubes :D
Post by: Jace the Gull on February 13, 2011, 11:26:24 AM
I did sign in but it still didn't work :-\
the member of the video may need to add your name to the list to allow you to see it.
Title: Re: What should we do with T8 fluorescent tubes :D
Post by: elektro666tech on February 14, 2011, 01:49:51 PM
Here are actualized links :-)
Shooting T8 from spudgun: http://www.youtube.com/watch?v=olnioyv1xKc
Shooting T8 into the bricks ;D : http://www.youtube.com/watch?v=mFbFBYWXKSM
T8 crash test ;) : http://www.youtube.com/watch?v=dCU71BL1sFk

Enjoy :) I hope that links works correctly
Title: Re: What should we do with T8 fluorescent tubes :D
Post by: elektro666tech on April 24, 2011, 11:38:08 AM
All links works correct, you can see and comment the video :-)