Sylvannia Curly Lightbulb Won't Shut Off

It sounds as if the switch isn't always opening.

Call Ghost Busters.

The only thing I found on the internet didn't make any sense to me.

That was that CFL bulbs don't tolerate heat well.

The only thing I can figure is this bulb is telling you that there are some induced currents in the wiring after the circuit/switch is turned off. I'm not sure this would show up on a normal meter.

Other opinions to follow, I'm sure.

Sounds like the overunity canceling circuit in the bulb is going bad.

clearly the switch is failing

this does sound like the neutral leg in this circuit is being switched leaving the fixture connected to the line voltage and there is a high resistance connection in the fixture or the neutral wire to ground. This would not show up with an incandescent bulb.

The bulb or the switch?

I've had no incidents since I changed the bulb. When the switch is OFF, I read no current on my tester? However, putting that errant bulb back in starts the blinking.

Now, that bulb has been in that fixture for about a year plus. Yes it is glass enclosed and there could have been a heat problem.

I'll change the switch just in case and so far, it looks like the problem was just with THAT one bulb.

What is "over unity canceling circuit in the bulb" ????

can only 1 switch activate this light? it wont light up without current so its getting a supply somewhere, lights don't store a reservoir

I have no idea. Some Electrician wired this room 15 odd years ago.

lights don't store a reservoir

Don't they? It seems these bulbs do have capacitators that store electrical energy.

What is "over unity canceling circuit in the bulb" It is a specially designed circuit so you cannot get light for free. It is a total conspiracy between the power company and the bulb manufacturers.

That was a sardonic joke he told because so many charlatans (we KNOW you are not one, don't sweat it) keep trying to sell us on "over-unity" energy generation devices, i.e., systems that supposedly take in no external power, and produce some usable amount of output power, generating the "excess" from some hitherto unknown (read that "magical") force of nature.

Over-Unity refers to an "equation" describing the input and output sides of the energy system where "input < output". Unity (and even that is impossible, unless all internal inefficiencies and losses are accounted for in detail) would be stated "input = output".

In real life systems (light bulbs of any kind are great examples) "input >>> usable output" (Is MUCH GREATER THAN. Factors of 10+) due to normal losses in energy conversion, heat, component resistance, etc.

As you can see from this, it was a joke, and truly has no bearing on your problem.

And it would probably have been much funnier without the explanation, but I've seen how hard you work at solving your design issues, and keeping them solved, so I figured you deserved the courtesy.

Bravo Sir ! GA to you, You shouldn't have self rated off-topic, but you'll get your post turned into a GA soon.

Do you have a transmitter or antenna close by the offending bulb? I remember in the day of CB radios that I could light fluorescent bulbs just by keying the mic on mine.

'course I might not have been completely legal in the output area.

Or possibly a microwave oven?

YES! I have a micro wave oven about 5 feet away from the fixture.

Now that'd be the reason why the overunity protection was damaged.

If this wass the source, you would only see the effect when the micowave oven was running.

Should be true. Netmaker, since this is on a boat or dock, is their a marine radar sweeping nearby? That would be much more likely to be running at odd times that a microwave, and much less likely in that environment to be noticed.

If there is, is the antenna inline with the lamp when it flickers? Either pointed at it, or (much less possible, and possibly a danger point) pointing directly away from it?

Toward it isn't much of an issue, as long as no human is in line with the feed horn, but given how much energy that would probably take to transmit the effect over much distance, I'd be looking into possible long-term tissue-cooking effects from a faulty installation and stray RF energy if that Radar were effecting it.

I can explain why the feed-horn orientation could cause a danger, but unless it looks like it might, I'd be wasting your time. Especially if competent marine-electrical engineering is already managing/monitoring that. And I'd be surprised if someone isn't, in your case. You seem to have your environment pretty-well squared away, from your previous posts.

That explanation makes sense. I do not understand all of it, but I have had these bulbs in other fixtures with no issues. Perhaps this one is just really sensitive.

The problem, as others have remarked, is most likely electrical leakage past the switch when it is off.

With both CFL and LED lamps, a few microamps of leakage will build up in a capacitor in the lamp's circuit until a threshold voltage is reached and then discharge through the lamp causing a flash which repeats regularly. Not enough leakage to make an incandescent lamp glow.

I have experienced that same problem several times here in the tropics, caused by both moisture in the switch wiring and also by tiny ants that get into the switch and become carbon resistors!

Ah. See my post 21, but I can see why, with designed in "leakage" current to a control device this could happen. NeilA, is that the case with your circuit, that there is an additional "control" device (dimmer, digital timer, occupancy sensor, etc.) in the circuit?

None of my questions will help NetMaker, probably, though it's always possible, but I need to understand what was flawed in my understanding, I think. Your answers will certainly help me with that, and subsequent research I'll undertake.

Thanks for indulging me. I know this is an excursion away from Netmaker's post.

Replying to your query, micahd02: no, in my cases there were no additional control devices, just resistive leakage due to moisture or a partially-conductive switch. The effect was of repeated distinct flashes every 1 to 5 seconds, rather than flickering but I guess that depends on the circuitry of the lamps. None of mine claim to be dimmer-compatible which may make a difference.

K Thanks. I DO need to do some research on this, then. If you find out anything else, please let me know. One of the problems this is causing me is that LEDs NEED extremely smooth DC, while CFLs NEED AC, with no DC component at all. Which means that whatever is happening in the "leaky" part of the circuit (AC, obviously) is perfectly suited to the CFL, except that you can't capacitively store AC. So the leakage is probably chopped by arcing within the switch. But NONE of that would reach the LED, since it is rectified and very heavily filtered by design, within the base circuitry included in the LED. So, the only effect of the problem which could reach the LED

(Ah, I think this might explain the entire thing to me)

is that the POWER (waveform not important at this point) reaching the LED circuitry is chopped (a dirty square wave, due to arcing, but effectively a square wave nonetheless).

If the LED circuitry cleans up the dirt from the arcing, it will by design pass the square wave without attenuating the leading and trailing edges (LED filters have to be very wide bandpass to provide a clean enough signal to the LED), which, if the signal has enough residual power (it doesn't take much, by design) it could still effect the electron orbit escalation in the atoms of the emitter chip, so that as they fall back they give off a faint amount of light. And since it IS intermittent, it would be a faint flicker.

There now, you've helped me immensely. I feel better because what I knew about LEDs is NOT negated by your observed experience, and I see better how LEDs integrate into existing AC circuits, and see some of the practical troubleshooting info I needed for the future, as well.

Most productive, and my heartfelt thanks for indulging me in the chase.

While an LED runs "best" with DC, it will light with AC, provided that the maximum reverse voltage (and the current limits) are not exceeded. It is, after all, just a diode, producing light when forward biased, and blocking current when reverse biased.

Exactly!

I have retrofitted neon indicator lamps with LEDS - I simply used a re-calculated series resistor and a series diode (to give higher reverse blocking) - there is a 60hz flicker because the LED is only on for half the wave form, but to indicate if a relay coil is picked up or not it was a dirt cheap fix.

Many auto led tail lamps also have an annoying flicker - when you scan past the tail light at night you can see the flicker - incadescent don't do that.

All of that is true, but only when the LEDs are not being driven at anything approaching maximum output, which socket-based-incandescent replacement LEDs are. And like most technologies nowadays, LEDs are indeed incredibly complacent with being abused as by a half-wave rectified, and unfiltered LOW voltage source; you did say that it is important not to exceed i(forward), so you are aware of this limitation, I know. The problem comes in when we apply an AC line voltage to an LED lamp, and push it for maximum light output. Heat goes up quickly in the control circuitry (LEDs do NOT produce heat directly, but heat in anywhere in the system can destroy and LED, or at least cause premature "droop" in output, which is permanent) and can render the LED either nearly unusable at half or less of it's intended light output, or destroy it outright. And unfiltered AC components in the drive voltage are one of the biggest culprits in this kind of loss. Hence, since we ARE talking about Netmaker's application being a socketed replacement for a commericially available incandescent, any AC in the line makes a LOT of difference.

Oh, yeah, and the way an LED produces light (I wasn't going to go into this, but, well, it will help) is that the DC voltage essentially injects a uni-directional energy into individual electrons orbiting (for want of a better word, but it isn't really an "orbit" per se) the nucleus of the atoms making up the LED emiitter. As the energy is injected into the electron (charges) they approach a higher than normal energy state, which speeds up their motion, causing them to move "up orbit" (think of a satellite that is stable in a mid-space orbit, maybe 5,000 miles up. Speed it up, and all things being equal, it will move higher into space, until the centripetal force holding it in orbit matches the kinetic energy of its flight around the orbit, and it stabilizes again).

But, unlike the satellite in the parenthetic example above, the electron does not "want" to be in that higher orbit. And it's energy state is higher than it "wants". Also, while it is "up there", there is a correspondingly empty hole in the valence shell of the atom.

So, the electron sheds energy as velocity, drops back down orbit, neatly slots in home, and the energy shed is delivered as light, in place of the pure electrical energy that it took on in the first place. But since more electrons are arriving by the micro-second (pesky tourists), the electron has to do the dance again, and again. But since AC power just kicks the energy level up on the rising side of a half-cycle, not far enough to reliably slot into a higher orbit, and then siphons it right back off about 180 degrees later, all you get is agitation of electrons, but no reliable light, and heat because of friction between electrons.

(Non sequitur alert)

Mad tourists with nothing to see because of a brown-out, crammed into an overcrowded and overbooked the hotel they didn't want, but stuck because they can't get elevated to something better with no better rooms or hotels available, and everybody else suffering the brown-out don't generate as much destruction as electrons in the same state. (Sorry, I'm reading a novel about tourists in South Florida in Summer. It strikes me that way. [; >~

And to think my kids want me to retire there. I just tell them I don't want to retire around a bunch of OLD PEOPLE. (End non sequitur alert)

So, for the sake of your LEDs, try to lay off the AC, OK?

You've seen LEDs do this? Do you know, at the electron shell orbit level why this is happening?

I recognize stored charge, an incipient oscillation in the charge storage/discharge cycle, but I would have thought that the analog wave-form most stray cycles of this nature generate would not push electrons "out-orbit" before the charge dissipated too far to be effective in this manner.

I obviously don't know enough about the attack/decay waveform of the energy packets that drives this conversion if a stray charge is causing flicker like that.

Don't know about lighting applications, but I've definitely known LED indicators to glow due to pickup from adjacent AC wiring in the loom.

Thanks. Direct induction (i.e., not just a stray charge stored capacitively, and "leaked" into the circuit) would fit my understanding much better. But this SOUNDED like the stored/leaked scenario, which is what set me off.

I agree with the induction process. I've seen it, too. Although, given the physic of LEDs, the induction has to happen "up-stream" from any power conditioning (rectification and filtering, primarily) which occur in the feed circuit to the LED.

And that WOULD be likely to happen in parallel wiring looms.

How old is the wiring in your house? In the "Dark Ages", prior to the 1950's, some lighting circuits were run with the neutral switched - not the line. (I got tingled real good washing a light fixture on my Grandfather's porch in the 1960's - switched neutral - house wiring dated to the 1920's.)

Very much so. This also sounds plausible.

Thank you.

Which part of the world are you in ? High humidity trapped in fixture results in grounding between fixture and CFL body- and so lamp may seem to stay on after it has been turned on for sometime. But never i dry climate of India.

I have experienced deadly shocks when I touched suitcases in German hotels (heavy carpets, heaters on in winters, closed windows). But never i dry climate of India.

Plenty of humidity in south Louisiana...much like near Mumbai or even Cochin along the coast. I worked in both areas and the humidity was much like at my home....only the Indian food was much hotter!! HA Ha !

I used to make these lamps before they sent the production line to China.

The concern about closed fixtures has to do with causing the "glow bottle" (aka Starting Switch) to become active after the lamp was operating.

The function of a ballast (and this glow bottle) is to create enough of an open circuit voltage to start the arc and then to limit the current after the arc is stabilized. If the ballast is a magnetic type, it is likely to be a choke which would allow leakage current to flow through it and the lamp coils as long as the glow bottle was cold (off). If enough leakage current flowed, and the glow bottle experienced 70 to 90 volts, it could start interacting. As someone pointed out, if you have one of those pilot illuminated switches, the possibility exists while the glow bottle is still warm. After it cools down, it is much less likely.

An electronic ballast needs significant power to create the same effect. It might still be possible but only while the lamp (and glow bottle) are still warm. The flash would be very brief, but you would definitely see it.

The flash was continuous for minutes...steady on and off blinking. It has not been repeated since I changed bulbs to an incandescent.

"The flash was continuous for minutes...steady on and off blinking"

This, in an LED, makes absolutely no sense at all, without some kind of complex chopper circuit working to provide power during the entire flash cycle. And it COULD, I suppose, be provided by a switch that was arcing internally, chopping the voltage. But THAT would not be in anyway predictably rhythmic, since by it's very nature the opening and closing of the arc is sporadic, chaotic, and random.

So, I understand everything else I've said or that has been said about LEDs, but I think all of what has been said going both directions is just academic discussion, in that it still doesn't begin to shed light on the problem Netmaker has posted, where the LEDs are concerned.

As far as CFLs go, I do not know enough about their control circuitry to try to decipher whether anything said her explains them behaving this way.

Over to you CFL guys on this, while I think some more about it.

Micahd standing by.

Sorry, momentarily back. Netmaker, I am making a perhaps invalid assumption. You said steady and blinking. I am assuming by that the flash was also very regular in frequency, timing, duration, intensity, etc. at least as far as you could observe with the naked eye (no one is asking for photos of Oscilloscope waveforms, or a Fourier Analysis here, just eyeballs). Is that right? Or was it sporadic and overall "flaky" where those factors are concerned, even though it continued for several minutes?

Micahd NOW by:

Forget LEDs in this discussion - that was an aside. Read the thread. It's about CFLs.

Forgotten. LEDs came up later. OTOH, I didn't understand what "Curly Bulbs" are. Curly must refer to the coiled shape of the CFLs actual tube, huh?

Duh....Yup!

Sometimes I'm slow.

Other times I'm really slow.

Today I'm trying to get up to speed with those other times.

Sorry if we were getting too technical for you.

Of course an incandescent bulb would not blink. It does not have a built in glow bottle.

I mis-spoke earlier, in that, it is the ballast that limits the current in a CFL or any fluorescent lamp. When power is applied, the glow bottle heats up causing the bi-metallic strip to close (and extinguish the glow plasma), thereby applying power to the coils to heat the coils. Then when the switch cools, it opens the switch, and there is an inductive voltage spike applied to the gas inside the lamp. If it ignites (ionizes) the gas, the open circuit impedance drops from mega-Ohms down to a couple hundred Ohms. This normally prevents the glow bottle from lighting up again.

In an Over Temperature Failure mode, the heat from the lamp causes the bimetal strip in the glow bottle to close, extinguishing the lamp and applying heat to the coils, and then cooling enough to strike the arc again.

This can only happen if power is applied and the lamp is in a sealed enclosure. I think you originally stated that you turned off the power and it kept running. Perhaps you only turned it off for a little while and tried it again before it had cooled for at least 15 minutes. In any case, all you need is some way to vent the fixture where the glow bottle resides (usually in the base).

Lastly, the CFL lamps made in the USA were "U" shaped or two of them joined together. The twisted glass bulb you described was made only in China.

NUOJ:

Thank you. I had never understood (NO, I didn't do my homework, either, in that I didn't look it up) exactly what the sequence of events t were which resulted in a glowing florescent light. You've enlightened me greatly. No pun intended.

But this in only for CFLs (or other florescent lights), and not for LEDs.

But netmaker (I THINK it was in netmaker's OP) said he saw LEDs do it, to. Anyway, SOMEONE in this thread said it. LEDs are the only reason I wrote all that techno-jargon about electron valence shells and up and down orbit motions.

It doesn't even apply (at least not that way) to florescent gases in an arc environment.

And if you DID get an LED into an arcing environment, you'd let the magic smoke out, and the dark would flow in and overload it permanently.

The LED reference was with respect to a pilot light in the switch allowing leakage current through the circuit. I don't think that could be responsible for the problem as it was described. It might cause an occasional but very brief flash. More likely, the glow bottle (auto start device) started to cycle after the fixture heated the whole thing up. CFL's have to have some air to prevent overheating of the glow bottle.

Here are a few observations I have noticed, I am not sure if they are related to your flickering led lamp issue.

I changed the incandescent lamps in my house to led bulbs in an effort to save money, I.e. less wattage, same lumens. In the bathroom while the led bulb was lit, it would sometimes flicker, when I replaced it with the original incandescent bulb the flickering would stop, I noticed that the inside of the fixtures socket had what looked like carbon tracking or corrosion marks, I thought that maybe, somehow the threads of the new led were different than the threads of the original bulb and could there be some type of resistance for the electrical path ? I put a replacement led bulb in, thinking that the first led bulb was somehow defective, same flickering occurred, so I changed the fixture socket and that cured the issue, no more flickering. My deduction was that the voltage requirements, or a consistently steady requirement was much more critical for an led bulb than for an incandescent, not being an electrical engineer, I had to don my sherlock Holmes hat. I thought about this some more, when I have used my clamp on amp meter to check the running apms on a cooler motor to verify within range on the motor name plate, I've noticed that in the hundredth digit there is a difference when using a new motor and and old harness and using a new motor and using a new harness, apparently the corrosion on the wire nut connected wires in the conduit box created the difference, when I cleaned the connections and put on new wire nuts the numbers on the meter were not so far apart

Useful.

Thank you.

And consistent with the OPs issue, if the blinking is random in duration, frequency, etc.

I guess we still have to wait for clarification on that.

it was one of those explosion proof ,glass enclosed,

Hold on a sec, is this Ex d light fitting installed in a hazardous area? Most (at least in Europe) aren't certified for use with CFL / LED lights because the electronics can overheat and potentially exceed the temperature rating of the fitting.

Be happy it didn't catch on fire! I had one that started emitting a smell like an electrical fire and the base turned brown, but I removed it before the flames started.

No more CFC lights in my house!

Things I have discovered using CFL's: The load on a switch becomes inductive, this becomes evident when the only switches available are substandard copies of questionable quality, especially three-way lamp switches. You can see and hear the effect on toggle wall switches. There is no longer information on what orientation ( base down, up, or horizontal) for operation printed on the packaging or the base of the bulb.

I'm surprised to see you refer to the new "Curly" style bulbs. I consider them old and environmentally dangerous, and am surprised that they are still available. They ARE more efficient than the still older incandescent bulbs, but they are very fragile and contain a small but significant amount of liquid mercury.

I've been replacing both incandescent and CFL lamps with LED lamps for several years. Most of the LED lamps are MUCH more robust than either the incandescent or CFL lamps. I still haven't quite finished the process, although I'm a big step closer, since Costco just came out with a Feit LED shop lamp. I just replaced a failed dual 4-foot Fluorescent with http://www.costco.com/Feit-Electric-4%E2%80%99-LED-Shop-Light-2-pack.product.100155638.html. The web page lists the unit at $90 for a two pack, but our local Costco is selling single units for $40. It claims 38W, compared to 80W for the standard balast-type fluorescent unit it replaces, and it gives off MUCH better light, to my eyes.

As to the flickering of a supposedly OFF lamp, I suspect it has to do with very low energy requirements to produce some small amount of light. Although it was originally posted relating to LEDs, it would probably also relate to other low energy lamps. Take a look at the thread including my post #61 of 2/7/13: http://cr4.globalspec.com/thread/82870#comment920170.

Fluorescent lamps have had their day because LED's out perform them. But if it is mercury you are worried about, then I suppose you don't mind giving up fossil fuels which contribute an enormous amount of mercury to the environment. In fact, if you put all the fluorescent lamps that have ever been made together you would only have a contribution equal to about 0.1% of all the sources of mercury in the environment.

Oh, and you better cap all of the active volcanoes in the world. They are major polluters.

No argument here. I and my students spilled significant amounts of mercury from physics experiments and broken thermometers, and I kept on teaching fo many years in the room I knew had significant amounts in the cracks between the floor tiles. As a kid I made more than a few silver coins shiny by coating them with mercury, and of course still have one or two amalgam fillings from at least half a century ago.

I've also held the lead based solder in my mouth while building and repairing electronic devices, and... Yet I'll reach the three-quarter century mark in a few months, and still have most of my body parts working reasonably well, so I do believe the bad effects of heavy metal exposure are greatly over-exaggerated for most people.

Still, the bad effects of excessive exposure to mercury have been documented at least since "Alice in wonderland", so I do believe in avoiding unnecessary pollution wherever possible.

I'm much more afraid of the direct and indirect effects of Roundup than I am of heavy metals, at least in the long run.

"Oh, and you better cap all of the active volcanoes in the world."

Now THAT would be an engineering feat to see! Especially when the Volcanoes got tired of it and all blew at once!

I know, it was figurative, but, sometimes, words just draw such an amazing picture, it can't be totally ignored.

Your noise source is most likely the microwave oven, but not when it's operating, but when it goes into "clock display" mode. There's that phantom power that is always being drawn, and though it's very low current, it can be electrically noisy, especially if the electrolytic capacitor closest to the input terminals is leaky.

Couple that with a poor ground and or neutral connection and you have the makings of what you're describing. Easy to check though, just unplug the microwave and see if the bulb still flickers, if not then your done, otherwise check every connection back to the breaker panel and the neutral bonding point, usually a quarter turn with a screwdriver cures everything.

I once had stray voltages, and when I looked in the darkened cabinet where the neutral was bonded to the water pipe, I could see a flickering blue glow, tightened the connection and clamp, problem solved.