Fluorescent Tube Lighting
Вставка
- Опубліковано 8 жов 2016
- A look at switch start linear fluorescent lighting, how the tube, starter and ballast are wired and theory of operation.
Also features an old more unusual type of tube connection.
Support this channel at Patreon: / jwflame
Twitter: / jwflame
Facebook: / jwflame
Instagram: / jwflame
Website: xo4.uk/?fLr
Contact info, sending stuff in etc.: xo4.uk/?YTT - Наука та технологія
I am a time served electrician of 58 years old.
I wish we had lecturers at college like John Ward when I was an apprentice!
Looking back, they just seemed to want to show how smart they were as opposed to training people.
Harry Harrison so true
Hi John I just wanted to thank you for all of your videos , I find them a great help.
that is the best explanation I have ever seen. I have looked at diagrams for years. never really understood how they actually worked? thanks
JW well done with these videos. Ive rewittien our safety documents of working with power in Australia for the company i work for. Everthing explained in so much detail and easy to follow.
Thanks for watching
John, your an excellent tutor without a doubt. Thanks very much for all your electrical tutorials
I don’t think I could get through college without your videos mr Ward, thank you. Great at explaining things
Hi John. Very interesting your video on fluorescent lighting. You have explained it very well. Look forward to more of your videos.
Another wonderful watch. JW's style is almost columboistical ... you think you've seen it all when JW pronounces "just one more thing" !I didn't know that I wanted to understand fluorescent tube fittings until I watched this, so once again many thanks to JW, who makes learning a pleasure. It was illuminating to see that the technology is essentially unchanged for over half a century. It is with a small sob I bid farewell to these icons of the lighting industry as I am about to upgrade my garage work area with LED downlighters .. sob.
Fantastic video, thanks John. With best wishes from the Netherlands!
Thanks very much for an excellent video. Now i finally understand whats happening in the starter.
Sooo good to watch - Great clarity - I learnt a lot.
Many thanks !
The only thing missing from the video was why the filaments at the end of the tube are pre heated, which is the same reason that CRT's in TV's and and monitors and valve's in old electronic equipment heat the filament to help them emit electrons. Once the tube is conducting I believe the current through the tube keeps the filaments hot.
I have a video suggestion. I think a lot of people are interested in converting their existing fluoro lights to use LED fluoro replacement tubes, but are put off by the need to make minor changes to the wiring. I think a video explaining how to do this and the issues to look out for would be great.
Thank you John, clear and concise. Appreciated.
Best explanation I've seen....thanks John...
I'd love to see that old B22 fitting working again! Maybe all it needs is a new ballast?
Very informative. Would be interesting to revisit this with some more of the older types you rarely see these days. The 4-pin thermal and twin glow starters spring to mind, ballast lamps, transformer quick start circuits etc.
I could always hear the damn things, glad to see them on the way out.
Thank you for your great videos, I appreciate them very much!
I've seen adapters for those b22 fittings so you could use a 2 pin tube
Excellent explanation John. There is one other mode of failure. When the filament burns out or breaks off, the bulb will not light . This is also true if the ballast is the starter less type. Even the high freq ballasts need a filament for the arc to land on. In the US we can still get most any T12 lamp including the HO variety, however, the VHO ,(very high output), are quite difficult to find.
Many thanks for such a clear explanation.
There is an adaptor kit for those old B22 tubes so you can retrofit a regular T12 5ft tube into them. plugs into the socket one end and has a pin holder the other end. Used for those historical places which want to keep the look of the old fixtures, and who can find a stock of 5ft T12 lamps ( in warm white of course, no cool white in the 1950's) to put in there.
As to the 3ft Thorn fitting, that is probably older than you John, it certainly predates the EMI buying of Thorn. The days when things were actually made in Britain, using British made steel and copper, and which were designed to last decades in use.
No random wrong apostrophes in the 1950s either...
Thank you for the detailed explanation.
Beautifully explained.
I echo Harry Harrison's sentiments exactly.
I too am a time-served spark.
(At 56, a couple of years younger though!)
Great video John! Thanks!
We are slowly replacing the oldest fittings at work, as and when they fail, due to the lamps being very hard to get hold of. They take 8ft 100w t12 tubes. Shame really, but the light output of a twin 5ft t5 is equivalent or even better, whilst only consuming 70w in total
Cracking video and excellent explanation. Cheers.
Excellent video. Thank you.
I needed this cheers.
excellent explanation 👌
Thank you John
Very informative, I do wonder if more that one person attempted to connect a fluorescent tube directly to the mains with one of those B22 fittings and experienced pretty disappointing results.
Would it be just a dim glow or would it pop the filament? The reason I ask is that the filaments weren't designed to self-limit their current like a normal bulb does - the ballast/choke is there to do that already. Straight on unballasted mains, wouldn't they just burn out?
The filament burns out with a bright flash and bang, sometimes knocking out the fuse, to make it glow you need only 12 volts. Only way for it to dimly glow on mains is when the filament is already broken, then it has just a gas discharge from buffer gas (argon or krypton) between the empty filament holders.
I would imagine as Big Clive would say "It went BANG!"
Good one J.W.
very educational thanks again
Great info
i just removed some 50 year old round sylvania fittings, still worked!
They recently replaced a lot of fluorescent fixtures at work, so I had a look if I could still use them as holders for LED tubes. When I saw the 1967 date on the back I gave up on the idea, the plastic on the ends was quite brittle as well.
But still, that's some amazing service life, considering that they were on most days. I doubt any of the electronic ballasts will last that long ;-)
Electronic ballasts vary wildly in quality, but if you get something decent they really can last in excess of 100000 hr rating... Indeed very old fluro's do last well (but even those I have had failures on, winding shorts out and you get a rather smelly meltdown).
Known as "preheat" in the States. But you didn't mention the cap across the starter. Believe that's there to allow AC current to flow between the tops of the filaments after the switch opens (after the starting pulse).
The cap across the starter is to filter out RFI when the starter is operating.
I have a couple of these fixtures in my garage. They're having issues starting up.
One day I noticed running my hand along the tube during startup excites the gases in the tube and it promptly lights.
Just thought I would share this little tidbit of information.
Tubes like to have a grounded metal strip running along their length to help start.
This might suggest the fixture isn't properly grounded
wonder if its static electricity helping ironisation
thanks great vid.
Are we ever going to see you play that organ? And sorry, I have to ask...are there ashes in that urn?
very interesting. do you have any videos regarding the organ in the background?
That nice vase. It's a storage for assorted parts, isn't it?
i don't hear a wife and kids so who knows!
I've noticed that some of the later fluorescent fixtures used here in Canada incorporated the starter and the ballast in one sealed unit. This is a pain, as if the starter fails, you have to replace the entire ballast unit.
Hi John. Great vid as ever. That said, could you 'do' one on the necessary conversion (re-wiring) needed for them to run LED tubes? I get that it is to do with removing the choke / ballast and replacing the starter with a fuse instead but am not 100% sure of the revised set up. Thanks.
Most clearly explained... as usual :) Question - does the fitting's metal case need to be grounded?
T12 tubes are still made for medical usage,UV killers(bug zapper),and standard T12 lamps are still made by Philips.
Thanks!
Hi JW i want to power in my workshop so i will need 2x16amp plus normal plugs sockets double ones to run compressor and 2 cnc machines one being a milling machine plus lighting so could you advise on what i will need swg armoured cable thanks Rob
John.....thanks very much for your videos, they are very informative for a keen amateur like me.....I've never understood how these tubes work but now do. You mention "power factor in another video"...is that one you've done? I can't find it on your channel.
Power factor hasn't been done yet.
A quick query - will the filaments not begin glowing as soon as power is applied, even if the filament circuit is closed at that point via the neon gas? The implication is that the filaments won't heat until the starter's bimetallic switch closes, but I thought that was merely the instant before starting circuit reverts to open-circuit state, because the bimetallic strip is no longer being heated.
Being a electrician as I am forever that's is a thorn 3ft fluorescent light fitting it's runs off on a 240v.30w ballast and via that 3ft 30w t8 thorn fluorescent tube.and should have a thorn 155/500.4--65w.200-250v starter lamp switch made in great Britain items.must be in use for that 3ft 30w fluorescent tube light fitting.and that other starter lamp switch only in use a 6ft 70w t8 fluorescents tubes only.via that 70w 220-240v starter lamp switch.and have a good summer holiday there John ward.from this electrician that's me in general.
Well you live and learn another mystery explained..................................Cheers
thanks nice movie
Interesting video John. My garage light is the old bayonet type fluorescent light which looks very similar inside to that one you showed. It still works aswell which is a bonus. Shame the bulbs are no longer available though. Why is the old one near silent in operation yet a brand new one I have in the Kitchen I can hear humming away throughout the house?
The hum is caused by magnetostriction in the choke. Magnetic components (transformers, motors, chokes) used to be built with lower flux density, more margin to saturation of the iron, making them quieter. Now they push the iron really hard, to save on material and shipping weight (from china). It might also be some resonance in the case.
But a brand new fixture (as in bought in the last few years) really shouldn't have a magnetic ballast any more, it should be electronic, at least in the EU this is required by law. An electronic ballast shouldn't hum, it also lights up near instantly and does not have a starter.
If the hum bothers you replace the tube with a LED retrofit tube. Even as a drop-in replacement the reduction in current draw should stop any hum, and you can remove the choke if all else fails since LED tubes do not need it at all. Most old fixtures can be retrofitted with LED tubes at lower cost than replacing them, as long as the fixture is still in decent shape mechanically.
I don't know the date, but adaptors were made to enable the bi pin tubes to be used with the old fittings that had the B22 lampholders at each end.
John
What is the oldest present tube light you have found?
My friend has one that came out of the back of a bakers van 40 years ago, he has used it in various caravans and living boxes overs the years and it is still running!
He has never changed the bulb in 40 years!
I have an old fluorescent fitting in my garage, dating from about 1959, which has a modern bi-pin tube in it but the starter has four pins. Does anyone know what that's all about?
I believe four pin starters used the extra pair of pins for a small heating coil that drives the bi-metallic starting mechanism in free air, predating the gas discharge 2 pin starter shown in this video.
Never seen that old type of connector before... :) (Of course it's about 10-20 years older then I am... :D)
Did you notice what excellent quality the fitting was, even though its obsolete? . Good old British manufacturing as it was after the war. Not like the flimsy foreign shite we have no choice but to buy nowadays.
That booklet you lifted up JW towards the end, below it I thought I saw an old Pyrotennex booklet, a cartoon guy in blue overalls. I remember looking at my Dad's booklet when I was little in the 60's or 70's, not a clue what the materials were about but I was fascinated by the cartoon character.
Perhaps you can show us through it one day.
What is the best way to determine if a flickering fluorescent tube is a faulty starter or tube?
The tube goes visibly black near the ends, which is usually a good sign of a well used lamp. But a faulty starter may take a long time after power is applied before it attempts to strike the tube, or it may not attempt at all. Blink happy fixtures usually means a worn out tube, the starter is trying its best but the tube can't successfully strike anymore with the supplied voltage.
whats make the bimetallic contact open the circuit itself ?
Hi John, have you done a video about HOW TO CONVERT FLUORESCENT TO LED light please?
is there any way to check with multimeter one of these tubes if it works?
You can indeed check between the pairs of pins on one end or the other for continuity, to ensure the filaments are still intact. BUT, there is no way to check for a working tube long-ways across the gas in the tube with just a multi-meter. Need to just stick it in a fixture for that :)
Can you do a video on the pro/cons of the electronic vs older ballast? Thanks.
Its pretty easy to compare and contrast the two types. older "magnetic" ballasts/chokes are by far more rugged and used to be cheaper to produce, after all they are just a coil of wire on an iron core so they practically never fail. But they fall short on efficiency, wasting a fair bit of power as heat, and can leave a visible flicker and audible hum of 50 or 60Hz, corresponding to your countries mains frequency.
Electronic ballasts offer greater energy efficiency and usually operate the tubes at high frequencies, which means flicker-free and hum-free. But the "instant start" variety can be pretty rough on the tubes, by not preheating the filaments at all and forcing them to start with a high voltage pulse.
So basically it comes down to magnetic ballasts are tried and true, but everything is solid state circuitry nowadays and you can't really find many (if any) magnetic ballast fixtures anymore. Gone the way of the incandescent light bulb.
Exactly...
Second-hand / new-old-stock Tridonic ballasts are easy to find and very good quality, very long lifetime, much better than magnetics...
Did you say you have done a video on power factor or are going to? If you've already done one could you put a link up here, please? I couldn't find it with a normal search.
cheers. :)
Not done yet, it's on the list of videos to do.
Hi, What is the wire/ conductor that is used for the internal wiring?
Solid core, single insulated. Not sure of the size, but probably 1.mm² or similar (this video was made over a year ago).
How would you connect an extractor fan to this?
I think actually the ballast includes some kind of voltage inverter/booster to increase the voltage to start the current through the gas in the tube - as it's high resistance. So the circuit diagram drawn in the vid is not right(?) my monitor has to inverters on the power board and is marked very high voltage so I that is why I think this involves very high voltage to get the lamp/tube started - some kind of transformer/inverter in the ballast. I could be wrong.
Old ballasts like the one in the video are just a big coil of wire on an iron core.
New lighting and other items such as monitors will contain 'ballasts' which are actually electronic circuits.
This video format is Big Clive ish 😊
So once the tube has been struck, it is driven cold cathode style? Or are the filaments self heating?
the filaments are heated duig striking via the starter, once struck the current flow keeps the warm, thats why when a tube dies and fails to strike, the ends start to glow due to the starter not kicking open cicuit
John McLaughlin Ah, I figured as much.
Any fixture with a starter or so-called "preheat" fixtures should not cause constant glowing filaments, unless the starter happens to weld its contacts closed. I believe its rapid start ballasts that fail in that manner, but do not use a self-contained starter as such.
didn't know that thanks :)
I've noticed that in the USA, the heater elements are always being energised. This is quite unlike the fluorescent tubes in the UK which are only energised during striking. This does result in different behaviour during failure.
Can Led Ribbon Lighting and fluorescent Tube be on the same circuit... controlled by a 30 year old Switch...?
i want that light my autistic lad collects fluorescents and i aint seen a bc fitting for 30 years
If the starter is just a switch then why are there so many different rated starters and what happens if you use the wrong starter?
Thanks for the video! Do you have one, or will make one, on how instant start fluorescent tubes work? They are still fairly common in the U.S. - in supermarkets, for example. They are 8 foot T12 tubes with ONE pin on each end.
How old is Your tube with Bayonet caps ?
At least 50 years, they haven't been made since the 1960s.
@@jwflame Hmm i saw that these tubes where stopped manufacturing in 1980s ?Where you found this Bayonet cap tube ?
This one was removed from an old house, it was in the attic and hadn't worked for many years.
I have a stores full of the old T12s, don't know why i kept them!
whereas i need some 6ft t12, hard to find! i have about 1 spare, and then i will have to change fittings it seems
A 6ft T8 should work quite happily in the same fitting. The end connections are the same, just the tube itself is a smaller diameter.
ShokaLion thanks, will the ballasts (very old) be happy with them?
jusb1066 The existing ballasts should be fine yeah. That's exactly the arrangement I have in my garage; old T12 6 foot fittings with 6 foot T8 tubes in them.
ShokaLion
cheers, ive checked, can easily find t8s,both in wickes or delivered at toolstation, well happy!
I work in a 24 hrs shop, and we rarely ever turn off the lights, we'd only use a couple of starter for a whole rows of light by connecting them, turn the light on and after the light has been started, remove the starter and move on to the next light as you don't need the starter while the light is on.
Quite a hassle when the power goes out though
What sort of stupid logic earning lots of money by running a 24hr shop but not spending pennies worth of starters for each light. Similar to car drivers in asia who switch off engines at traffic lights to save 6 drops of fuel but then pumping in 40 drops to get it restarted, not to forget wear and tear on battery and starter motor
If I decide to disconnect the ballast and put the line straight through for an LED tube, I take it the capacitor is irrelevant - if fitted at all. If it is fitted, is there any advantage in removing it?
LEDs are typically capacitive loads so another capacitor would make the power factor worse rather than improve it. Therefore best removed. However power factor is only relevant to larger commercial / industrial installations where it may affect the price paid for electricity.
Single tube for single tube circuits as oppose to a starter for multiple tubes at the same time? What are you talking about??? 'Single' starters are for use for single lamps circuits yes, but the other kind I think you are referring to are single/twin starters i.e. FS2 starters that operate a single tube of 4-22w on 110/120v ac or two 4-22w tubes in series (one starter for each tube) on 240V. Also 3' fluorescent tubes are still 30w. When you give erroneous statements it makes me doubt anything else you say!
Very out-of-date information, no more used that simple basic neon starter type fluorescent light, only can be found used in 15W type kitchen counter light.
3' and 6', strange, in australia i've really only seen 2' and 4' (18/36 watt or 20/40 for the fat ones) except for fish tanks
4', 5' and 6' are the most common here, with 5 probably slightly more popular. 3' are unusual and the tubes typically have to be ordered specially, 2' are available but seldom used - smaller fittings generally have folded tubes such as the 2D style.
8' tubes were common once in large shops and commercial buildings but are not manufactured now so most have been replaced.
I've actually noticed 6' variety noticeably more costly and hard to find specialist high quality tubes for, basically decided to settle on 5' variety as much as possible.
Despite the rise in popularity of some LED fits (of wildly varied quality), I have found very good value in HF Fluorescents (Tridonic PRO or ECO-dimmable ballasts) and special High-CRI tubes giving exceptional quality light =).
Why does your voice go from normal pitch to a high tone all the time? Very annoying.
We are slowly replacing the oldest fittings at work, as and when they fail, due to the lamps being very hard to get hold of. They take 8ft 100w t12 tubes. Shame really, but the light output of a twin 5ft t5 is equivalent or even better, whilst only consuming 70w in total
Note importantly, the T5 tubes are specified for use only with Electronic Ballasts.
T8 Tubes, confusingly, are 'rated' for use with Magnetic ballasts that waste considerable amount of energy again... e.g. 58w ballast with 20w lost in ballast
BUT when T8 ran with good electronic ballast similar to T5's they actually used LESS than that rating e.g. 50w + 5w in ballast (as well as giving more light, handling lots more start cycles, lasting longer, and giving non-stroboscopic light if the ballast is any good).