Electronic flourescent tube starter - Page 1
Forum section: electronics / beginners

author: jjj333
author_rank: Contributor
timestamp: June 17, 2022, 02:53:30 pm
content: Since these starters are very expensive, I thought of soldering a few myself.I saw a SIDAC circuit and bought a few of them, but it failed to work!I must be doing something wrong! My tube has no capacitor. Maybe it's that why it won't work?Here's a page that shows more of how they work:https://www.bristolwatch.com/ele/sidac.htmI'm in N-Australia and we got 240VAC, so I built this circuit:

author: Kyle_from_somewhere
author_rank: Regular Contributor
timestamp: June 17, 2022, 03:28:23 pm
content: It would be better to just buy a starter, they only cost a few cents and are disposable parts.I think that you are using the wrong search terms if what you find is expensive.

author: Zero999
author_rank: Super Contributor
timestamp: June 17, 2022, 05:08:39 pm
content: Why not upgrade to LED?

author: retiredfeline
author_rank: Frequent Contributor
timestamp: June 17, 2022, 05:54:57 pm
content: https://www.bunnings.com.au/osram-fluorescent-tube-starter-2-pack_p4320433< $1 qty 25

author: Benta
author_rank: Super Contributor
timestamp: June 17, 2022, 06:39:58 pm
content: Dunno what you mean by "very expensive". I see them at 3...10 Euro. Example:https://www.amazon.de/Globe-Warehouse-Leuchtstoffr%C3%B6hren-Schnell-Starter-4-125W/dp/B00LSKTVHE

author: jjj333
author_rank: Contributor
timestamp: June 18, 2022, 01:18:21 am
content: Thank you for all the price comparisons. - Actually, I was l rather looking for some truly technical advice on why the circuit fails to work?Yes, that would really help me.

author: Kyle_from_somewhere
author_rank: Regular Contributor
timestamp: June 18, 2022, 01:24:12 am
content: Quote from: Zero999 on June 17, 2022, 05:08:39 pmI think that's usually covered by the "boots theory".

author: Circlotron
author_rank: Super Contributor
timestamp: June 18, 2022, 02:49:35 am
content: I really don't think that circuit is going to work as well as expected. When the voltage across the SIDAC gets high enough it turns on and shunts the tube, causing the filaments to heat. Then they turn off at or near the current zero crossing and so is unlikely to produce a high voltage kick great enough to make the tube strike. After the filaments have heated, that side of the circuit needs to be opened at thepeakof the current waveform to enable the iron cored ballast inductor to provided the needed striking voltage.

author: jjj333
author_rank: Contributor
timestamp: June 18, 2022, 05:50:09 am
content: Thank youCirclotronfor that. I don't know why they show this circuit if it fails to work? I liked it because it uses only a few parts.On Youtube a technician soldered a circuit for a fluorescent tube without a starter. He didn't show the circuit schematic of it, but I worked it out; for it's merely a rectifier. Q: Why has the tube only one wire on each side? How can it heat the filament? I wonder if it works on 240VAC (of course with the certified Caps or 600V) ones.)()

author: jonpaul
author_rank: Super Contributor
timestamp: June 18, 2022, 06:46:56 am
content: lighting Industry used electronic ballasts since 1970s.After 1990s, Hg fl lams are phased out due to mercurynowadays we use LEDs.Your circuit cannot workJon

author: Zero999
author_rank: Super Contributor
timestamp: June 18, 2022, 08:06:51 am
content: Quote from: Kyle_from_somewhere on June 18, 2022, 01:24:12 amWhat’ the boots theory?

author: strawberry
author_rank: Super Contributor
timestamp: June 18, 2022, 09:39:50 am
content: sidac firing voltage might be too high 2x240V for mans voltage 340V or something to do with ballast inductance...heated filament reduce tube firing voltagecould use cold cathode HV ignition circuit(fire small transformer to ignite tube at mains peak)

author: Gyro
author_rank: Super Contributor
timestamp: June 18, 2022, 09:54:43 am
content: ... although cold cathode start wouldn't be good for tube end blackening.

author: SeanB
author_rank: Super Contributor
timestamp: June 18, 2022, 10:54:12 am
content: Just use the single device in circuit, not 2 in series. The sidac will turn on and start to heat the cathodes, and then at every zero crossing will turn off, and once the cathodes are hot they will start the tube conducting, which clamps the voltage across the tube to around 90V, so the sidac will then stay off till the tube is turned off long enough for the heaters to get cold.The electronic starters use a bridge rectifier to make DC, then a simple thyristor to short the tube when power is applied, with a sidac or series diacs to get the thyristor to trigger at around 140VDC across the pins. Then there is a second circuit, consisting of a high value resistor fed from the bridge rectifier, which charges a capacitor up to turn on a transistor, via a low leakage high voltage zener diode, that shorts out the gate of the thyristor, so it will not fire. This is there for EOL of the tube, so it will attempt to heat the cathodes for around 30 seconds, then shut down and refuse to try to heat the tube at EOL, so it stays off, and does not keep trying to flicker and start. Other types use a triac, and a single diode to rectify the incoming voltage to drive the sidac and sense circuit, same principles.

author: Kyle_from_somewhere
author_rank: Regular Contributor
timestamp: June 18, 2022, 04:01:01 pm
content: Quote from: Zero999 on June 18, 2022, 08:06:51 amOften people with a limited budget will buy something cheap, that then doesn't last very long, or costs a lot to run. But if you have more money, you can buy something that's expensive at first, but costs so little afterwards that it works out cheaper over time. Boots are the most famous example.Fluorescent tubes fit the model perfectly. Half the cost to buy but twice as expensive to run, and when they broke I could usually only afford to replace it with another identical one. When I got a windfall I banished them all from my house.

author: strawberry
author_rank: Super Contributor
timestamp: June 18, 2022, 08:07:52 pm
content: gas discharge and incandescent light sources are more reliable even after 50y of storageLED electronics(electrolytics, moisture sensitive circuits) most LED are indoor use only

author: Wallace Gasiewicz
author_rank: Super Contributor
timestamp: June 18, 2022, 10:28:18 pm
content: Some fluorescent systems cause a lot of RF pollution. I think the electronic starter is the one. You have to weigh the potential of interference in your particular application. A bad fluorescent lighting situation is quite problematic if you are working with RF.

author: jjj333
author_rank: Contributor
timestamp: June 19, 2022, 01:18:08 am
content: Thank youstrawberry, Gyro & Seanfor your good advice. The thing I'm still missing is a working SIDAC circuit for the 240VAC power supply we got here. So I can far easier solder several of these instant starters because I bought 20 of these SIDAC devices. - I saw this EA circuit on Google, but I love circuits, which achieve their objective with minimal components and they are easier to build. That's why I bought these SIDACs.I live on an age pension and that's why I need every dollar for food and basics.- Sadly, since non-of the expert technicians in this forum is able to help me make the SIDAC circuit work, I'm forced to forget and lose the SIDACs ($40) I bought and settle for this EA circuit, using 8 parts; since I only need to buy 15x cheap B151-500R. I'll just Uhu-glue the parts onto small pieces of table gladding (sample) material and wire/solder 15 of them up for all my fluorescent tubes.

author: jjj333
author_rank: Contributor
timestamp: June 23, 2022, 01:16:25 am
content: Quote from: Kyle_from_somewhere on June 17, 2022, 03:28:23 pmI have lots of those ordinary "tube eater flicker starters". I just had a look on eBay for these Instant Electronic Fluoro Tube Starters:they ask $30.85 to $73.95 for eachlousy starter.I'm sure your "search term" found instant or electronic fluorescent starters at "only a few cents" each. Be so kind as to tell me where they sell at this low price? Thank you in advance...Since I have less money, but more time "it would be better" and far cheaper to solder 15 of them myself. - Don't you think so?

author: Kyle_from_somewhere
author_rank: Regular Contributor
timestamp: June 23, 2022, 04:51:30 am
content: I don't understand why you're having this difficulty. You can buy them in big packs at the hardware store for less than a dollar each

author: Zero999
author_rank: Super Contributor
timestamp: June 23, 2022, 06:20:18 am
content: Quote from: Kyle_from_somewhere on June 23, 2022, 04:51:30 amThose are the old flicker starters, consisting of a glass bulb filled with argon at a low pressure and a bimetal strip. The original poster wants electronic starters which have a TRIAC circuit.Quote from: jjj333 on June 23, 2022, 01:16:25 amIt's hard luck I'm afraid. Electronic starters are expensive and probably won't get any cheaper, unless you can get some surplus stock.You have three choices:Stick with a glow starter.Replace the ballast with an electronic one. This will probably only cost a bit more than an electronic starter and save money in long run, as the tubes will last longer.Change the lamps for LED. This will save even more money in the long run, as LEDs use less power. Don't cheap out, buy quality.You could make your own electronic starters, but it's not worth it, which is why I didn't include it in the list of options.

author: jjj333
author_rank: Contributor
timestamp: June 23, 2022, 07:33:11 am
content: Thank you Kyle from somewhere for your options. In my case, your best option may not benefit me, for I may be dead by then...So I chose the 4th option and already ordered 20 of these BT151-500R for only $5.27 incl. postage from AliExpress. The other parts I already have in stock. So, as soon the BT151 arrives I'm going to (Uhu-) glue and wire up the parts. I already prepared some old flicker starters for that purpose. I think it won't take me more than 1-2 workdays, for I constructed far more complex circuits successfully. That much practice I have.End of the problem.- I just tried my luck here in this forum with my SIDAC circuit consisting of only 4 parts. Sadly, none of you experts were able to make this SIDAC circuit work... Hence, I have to rely on ("help yourself so helps you, God") my limited knowledge and practical experience.

author: strawberry
author_rank: Super Contributor
timestamp: June 23, 2022, 09:19:18 am
content: Quotedone some raw estimates with LED vs fluorescent tube. both gave ~100lumen/W (both in compact socket E27...version is much worse)they make general LED tubes less rated power so to appear significantly more efficient(or maybe they cant dissipate enough heat in that same form factor) LEDs get really hot and that accelerate wearoutfor LED point light source so must use light filters (eats efficiency)If someone can run LED chips at ~45degC they could last some 20..40years or until luminofor wearoutwearout vs temperature must be some exponential curve

author: Zero999
author_rank: Super Contributor
timestamp: June 23, 2022, 12:45:13 pm
content: Quote from: strawberry on June 23, 2022, 09:19:18 amI doubt the accuracy of your measurements. 100 lumen/W is pretty much as good as you're going to get from a fluorescent lamp. A good quality LED can more than double that. Generally modern white LEDs are just over twice as efficient as fluorescent tubes.Personally speaking, I haven't replaced all my CFLs with LED in one go, like I did with incandescent lamps. I just replace the bulb with LED, when it fails.

author: jjj333
author_rank: Contributor
timestamp: June 24, 2022, 07:44:10 am
content: All I needed is how to make the presented SIDAC starter circuit work because I built the simple circuit, but it just didn't work. - I'm not an electronic engineer, but able to build any working circuit successfully for as long it's a circuit that works!Thus, today I fiddled around with adding a 1uF capacitor; first in parallel which turned it on but made it buzz. Then I tried to connect the same Cap in series and it worked perfectly!!The original SIDAC starter circuit shows a 3uF3 Cap, but all of my lamps haven't got this Cap. That's why my SIDAC circuit didn't work without any Cap. I simply didn't know that!I just built the SIDAC starter circuit without that Cap... and that's why it failed to work! For that, I needed your expert help!That's a bit crazy but that's how electronics function; one wrong or missing part or connection and it fails to work. You know that...Hence, my working SIDAC starter circuit should rather look like this:

author: CaptDon
author_rank: Super Contributor
timestamp: June 24, 2022, 01:41:27 pm
content: I think part of the problem is that capacitor you keep putting in series. I guess it is for power factor correction but it is being used in a wrong way. I would maybe put that capacitor on the line side of the ballast across the line and probably add a fuse in case the capacitor shorts. In your original diagram you are creating a certain amount of Xl and immediately offsetting it with Xc so the impedance ends up being Xl - Xc. Here in 120vac land we only see a ballast and a starter. Generally the starter has a .01uf at 1Kv ceramic capacitor in parallel inside the starter. If the starter opens during the part of the cycle where the the voltage isn't enough to fire the lamp it will re-strike another time or more.

author: jjj333
author_rank: Contributor
timestamp: June 24, 2022, 02:53:06 pm
content: Quote from: CaptDon on June 24, 2022, 01:41:27 pmFrom what I can observe putting the capacitor in series works perfectly. Everything seems to work normally after the instant start. Nothing gets hotter than normal and I started the tube instantly over 20 times. I'll see if it causes any problems in the long run.Changing to LED tubes is not an option for me, because I have got 24 solar panels on top of the roof and don't pay for electricity. Bad luck Putin!

author: strawberry
author_rank: Super Contributor
timestamp: June 24, 2022, 03:28:30 pm
content: Quote from: Zero999 on June 23, 2022, 12:45:13 pmT8 18W = 1200..1800lmT8 9W = 1200lm / osram 7W = 1100lmLED is more efficient100k hours is theoretical life for LED chip at room temperature (in practice got to run x4)white LED efficiency drops by 20% @100degCneed new lamp designs for better thermal management and forget about E27 T8 T5 .... nostalgic retrofit rubbish

author: jjj333
author_rank: Contributor
timestamp: June 28, 2022, 12:00:33 pm
content: I did the testing on a smaller circled fluorescent tube and noticed that bigger tubes require at least 3.3uF Caps. Since these caps are expensive I substituted them with cheap 2 x 10uF (5uF) and they really work well. Since I cannot fit them into the starter body, I solder them onto a 10cm long wire. So I can hook them on top of the lamp's metal frame. I insulate all 240VAC connections with masking take and a few drops of white water glue.Safety: I used this masking tape insulation method for 50 years without a problem. After the water glue dries it makes it very lasting (over 20 years!) Well, any other insulation method/ housing, unless it's fireproof, will burn off as well when something goes wrong. - Even if it burns off, little damage will occur, because it's up in the air near the lamp metal. End of drama !!

author: Shock
author_rank: Super Contributor
timestamp: June 29, 2022, 01:33:47 pm
content: When your house burns down (and insurance doesn't pay out) because you tried to save a few bucks on a repairing a starter come back and let us know. Most of them fail due to faulty caps but if the fluro is dying it can lead you to think it's a starter problem when it's actually just a tired tube.I brought a bunch of decommissioned hanging fluro fittings from a temporary install and they each came with the bulb and starter. So almost have a lifetime supply, I find it amusing when the wife says one is broken and 5 mins later it's back working. Used to be annoying going out to get a starter to find it was the bulb and vice versa.As they were temporary installed they each have a mains plug and socket and someone must have daisy chained them up in a big loop (am sure that ain't code). The nice part is they were all steel hanging workshop style fittings and the plugs sockets are salvageable.So not only can I run them with LEDs when I expand my workshop later but they will last forever and the spares are going up in value and keeping me in parts. For a few bucks a piece it's been a bargain. I got some high quality low hours mains switches and sockets in the same manner so instead of buying chinese junk that doesn't match I just supply my own stock. In 20 years 3 fittings have died so I've saved about $40 so far. Living the dream lol.

author: SeanB
author_rank: Super Contributor
timestamp: July 09, 2022, 09:52:08 am
content: Also got a supply of tubes of various types, mostly used for corridor lighting. So far the 4 Osram LED retrofits are doing well, on 24/7/365 except during rotational load shedding, but since they were the more expensive type, costing 4 times the regular Osram one, I would say they might actually reach the design life. Regular tubes last around 5 years, running off a daylight switch and well oversized contactor, so I do have a decade or so of spare lamps for there. The low power tubes that came out at the same time as LED, 13W instead of 18, using the same ballast and an electronic starter, did not last as long, likely due to the lower mercury dose, but those starters are still going strong with new regular 18W tubes.