Author Topic: Small UK owned streetlight design company cannot design own LED drivers?  (Read 4002 times)

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Offline treez

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Hello My friend works for a small  Street-lighting company in the North of UK.
He says  that  whilst working there he is condemned to never being able to use his SMPS design skills…is this likely to be true?   :-//
His company buy  offline LED drivers  as follows from eg Philips………………
http://www.docs.lighting.philips.com/en_gb/oem/download/xitanium-led-drivers-outdoor/Xitanium_150W_0.1-1.05A_Prog_GL-F_sXt_929000709003.pdf

…they then fit these offtheshelf  LED drivers into the lamp head, and voila….sell the streetlight.   :clap:

Electrolytic capacitors
All the available offtheshelf , offline, isolated  LED  drivers  for streetlighting , contain electrolytic capacitors. This is because  this is the only practical way of preventing serious levels of 100Hz flicker in the light of the LED streetlight. (film capacitors could be used to help prevent high levels of  100Hz flicker, but it would be way too expensive to replace electrolytics with film capacitors) Serious 100Hz flicker is not illegal for streetlighting  (neither is it in any way harmful)…however,  high levels of 100Hz flicker are illegal in Europe for indoor lighting…and the fact that this is the case, is used as a scaremongering tactic to deter  European customers from even accepting high levels of  100Hz flicker in streetlighting.

Electrolytic capacitor free streetlight driver
Anyway….he was told by his boss that he would be tasked with designing Electrolytic capacitor free offline streetlight drivers using SMPS……(the boss even managed to get a business development grant in order to investigate this)……the thing is, the 100Hz flicker problem virtually certainly means that this project is a hopeless  loss maker……..seriously 100Hz flickering streetlights are never going to sell …at least not anywhere in Europe. (there’s no sane reason for this, but its just the way things are and will stay.)
Not only that, but a reasonably priced, isolated  offline electrolytic-capacitor-free streetlight driver would likely use a single_stage_Flyback SMPS……..Due to being a Flyback, (and the high RMS current in it since it appears straight after the unsmoothed mains bridge output) such a converter would likely be less efficient than  an offline led driver comprising a Boost PFC followed by say a 2-transistor-forward converter. (admittedly the latter would have an electrolytic capacitor bank after the Boost PFC stage……but it would likely be more efficient than a single_stage_Flyback of the same power level….so its another nail in the coffin of the electrolytic-capacitor-free, isolated LED streetlight driver…(OK there are ways of doing it more efficiently, but these are too expensive)

As such, my friend believes that this electrolytic-capacitor-free streetlight driver task that he has been tasked with is a "no-hoper"…  :horse:  as soon as the Business development fund money has run out….then so will the task just  die off.

Compete with the major electronics corporations
The other alternative is to actually design an offline, isolated LED streetlight driver with electrolytic capacitors and try and compete with the major electronics corporations such as Philips, Tridonic, Osram, Samsung etc etc…………….
This is surely hopeless…   :horse: ..there’s no way a small company would be able to get  the kind of component cost-downs that the big electronics corporations can. Not only that, but  the mainland European  electronics corporations, have benefit-clique style relations with the European semiconductor fabrication plants, so they can get components far cheaper than a UK company would be able to. (there are no major semiconductor fabrication plants in the UK, neither are there any  significant  UK owned electronics component makers).

So do you believe it is true?….can a small UK company never be able to design its own offline, isolated, SMPS based LED streetlight drivers as part of  competing in the streetlight sales arena?
The company are deterring him from trying to leave by saying that he will be able to design offline streetlight drivers at the company. In truth, he believes that this is never going to be the case…the streetlight market is one of huge volumes, and the huge European electronics corporations have  it totally wrapped up.

Chinese imports
My Friend believes  that the real reason that  they want him to stay…… is to do bits of general  software and general analog interface circuitry…something that in truth, they would be better off getting a different engineer for. Also, the company buys in lots of Chinese made SMPS based  lighting, and middle-mans it onward, and it is deemed that it  kind of helps to support this business if you have an  SMPS engineer in-house…(every now and then an imported  Chinese SMPS may fail, and it is deemed to help  if you have an engineer in house who can make out some kind of technical-sounding report on what  may have caused the failure)…..in truth, this job hardly needs anyone with SMPS design skills…since the company don’t even have the schematics of the Chines import products.
Another point, is that when UK leaves the EU…the UK government are likely to impose high  tariffs on these Chinese imports, and so this may well close down a lot of small UK owned lighting companys……..because the Chinese import business is said to be the major profit making activity of small UK owned lighting companies.

In the UK, there are actually a number of “electronics design” companys which are no more than “puppet companys”…pretending to be what they are, when in fact, the “real” company is in China…and the Chinese simply use the” UK company”  as a vehicle through which they can import their Chinese products into the UK and the EU  without paying the import tariff….the UK “puppet company” is usually a very convincing disguise…they are staffed with  British “engineers” and sales  staff etc etc…you would just think it was a totally British company….you would never realise that everything was being designed in China, and then transferred across to UK. The Chinese secretly direct all operations in the UK “puppet company”. I think the UK government will hunt down these puppets after Brexit, and impose huge tariffs on them…closing them down.

So do you believe it is true?….can a small company never be able to design its own offline, isolated LED streetlight drivers as part of  competing in the streetlight sales arena?   :-//

 8)

« Last Edit: August 05, 2018, 09:08:56 am by treez »
 

Offline tggzzz

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Are your other threads
https://www.eevblog.com/forum/chat/why-do-cash-strapped-electronics-manufacturers-in-uk-go-to-expensive-areas/msg1448687/#msg1448687
https://www.eevblog.com/forum/chat/how-does-a-small-company-start-making-led-streetlight-drivers/msg1442260/#msg1442260
https://www.eevblog.com/forum/projects/common-mode-emc-problem-in-offline-led-driver/msg1435168/#msg1435168
https://www.eevblog.com/forum/projects/mains-transient-protection-circuit-looks-very-bad-should-we-bin-it/msg1393480/#msg1393480
https://www.eevblog.com/forum/beginners/long-mains-cable-leading-to-product-filters-noise-out-or-brings-more-noise-in/msg1373512/#msg1373512
in any way relevant or associated with this topic?

Hello My friend works for a small  Street-lighting company in the North of UK.
He says  that  whilst working there he is condemned to never being able to use his SMPS design skills…is this likely to be true?

"Your friend" in the "North" should ignore his engineering judgement and believe everything that other people tell him, without reservation. Or not.

Quote
As such, my friend believes that this electrolytic-capacitor-free streetlight driver task that he has been tasked with is a "no-hoper"…as soon as the Business development fund money has run out….then so will the task just  die off.

My Friend believes  that the real reason that  they want him to stay…… is to do bits of general  software and general analog interface circuitry…something that in truth, they would be better off getting a different engineer for. Also, the company buys in lots of Chinese made SMPS based  lighting, and middle-mans it onward, and it is deemed that it  kind of helps to support this business if you have an  SMPS engineer in-house…(every now and then an imported  Chinese SMPS may fail, and it is deemed to help  if you have an engineer in house who can make out some kind of technical-sounding report on what  may have caused the failure)…..in truth, this job hardly needs anyone with SMPS design skills…since the company don’t even have the schematics of the Chines import products.

If "your friend" is unhappy, they should leave and become a consultant.
If "your friend's" calling in life is to design SMPSs, then they should emmigrate to somewhere where SMPSs are designed.
Othewise they will have to compromise and change.

Quote
So do you believe it is true?….can a small company never be able to design its own offline, isolated LED streetlight drivers as part of  competing in the streetlight sales arena?   :-//

Of course they can design one.
« Last Edit: August 05, 2018, 09:13:21 am by tggzzz »
There are lies, damned lies, statistics - and ADC/DAC specs.
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Online Zero999

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I do think a lot of flicker would be a problem with street lights. I've noticed it with old sodium lights and found it distracting. An LED light with a large chain of LEDs and a capacitive dropper could be worse, as the duty cycle would be low.

Not using electrolytic capacitors, sounds daft to me. They can be very reliable, if used properly. There are some power supplies where I work which have electrolytic capacitors and have been continuously powered for over a decade with no problems.

There could be other reasons for needing large capacitors, such as power factor correction, which might be a requirements for modern street light LED drivers.

Of course it's possible for a small company to design their own LED driver, but whether it's profitable to do so or not is another matter.
 
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Offline treez

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Thanks, I believe there is some SMPS design work in UK….but generally for low volume markets….or startup companies who just need some power in whatever physical space to power whatever prototype they have.
Also, I appreciate that you both know that a single stage Flyback PFC LED driver can be done,  and not need any electrolytic capacitors (no large capacitor banks)..and be PFC’d

Quote
I do think a lot of flicker would be a problem with street lights.
Thanks, whether it is or not...the public have been whipped up into such a furore of fear of high levels of 100Hz flicker that there is no chance of selling these kind  of lamps into the streetlighting market. In my opinion.....it doesnt matter for streetlighting.

Ive never seen a light output waveform for a sodium streetlight, but i understood that their "persistence"  meant that they dont flicker at all?
« Last Edit: August 05, 2018, 09:21:39 am by treez »
 

Offline tggzzz

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Thanks, whether it is or not...the public have been whipped up into such a furore of fear of high levels of 100Hz flicker that there is no chance of selling these kind  of lamps into the streetlighting market. In my opinion.....it doesnt matter for streetlighting.

Some people are more sensitive to flicker than others. Hence your not being affected isn't a good indicator.

Quote
Ive never seen a light output waveform for a sodium streetlight, but i understood that their "persistence"  meant that they dont flicker at all?

Have you tried measuring it?
There are lies, damned lies, statistics - and ADC/DAC specs.
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Online jpanhalt

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@treez
This question seems to be a recurring theme for the more than 4 years I have read your posts, e.g., https://www.electro-tech-online.com/threads/uk-universities-have-stopped-teaching-analog-electronics-on-electronics-degree-courses.139537/#post-1162906

Remember, you can't do great things, if you are not there.   "Being there" means accepting what you can't change and contributing to what you can.  Or, start your own business.

I suspect you are in the former group.  So, at your next job, show you know how to make a decision without worrying it to death on the Internet.

With best regards, John
 
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Offline bob225

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At the end of the day its down to cost,

Why R&D and spin your own when you can buy in the equivalent electronics from a supplier with years of experience in the field and they have the items on the shelf for when you need them with warrantee

or

£50-70k a year engineer, tied up for possibly years on 1 project with £100k worth of inventory and a lab full of equipment - then the cost of having the equipment certified and not forgetting you will have stock sitting on the shelf, EOL comes around and its dead stock only fit for the skip
 
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Online NivagSwerdna

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He says  that  whilst working there he is condemned to never being able to use his SMPS design skills…is this likely to be true?   :-//
His company buy  offline LED drivers  as follows from eg Philips………………
http://www.docs.lighting.philips.com/en_gb/oem/download/xitanium-led-drivers-outdoor/Xitanium_150W_0.1-1.05A_Prog_GL-F_sXt_929000709003.pdf

…they then fit these offtheshelf  LED drivers into the lamp head, and voila….sell the streetlight.   :clap:
And they make money?  If so, it's a winner.

The alternative has huge risks and potentially limited up-side.  Maybe your friends design skills aren't up to those in the competing product, maybe the cost of the development cycle would be high, maybe sourcing individual components and assembly would be problematic.  In summary maybe it's just not worth the risk/cost of in-house?
 
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Offline IanB

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The obvious question here is about the difference between design and manufacture. If Phillips sells a power supply module for lighting, do you think, maybe, that Phillips had in-house engineers design it? And that perhaps those engineers were based in Europe?

Maybe Phillips has significant expertise in this area built up over the years with a staff of very experienced designers who have done many, many products in their career?

Maybe Phillips doesn't just go out to the Shenzhen marketplace and pick an off-the-shelf product to buy and re-sell that ticks certain boxes?
I'm not an EE--what am I doing here?
 
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Online Zero999

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Ive never seen a light output waveform for a sodium streetlight, but i understood that their "persistence"  meant that they dont flicker at all?
Why would there be any persistence in a sodium discharge lamp? There's no phosphor. When the current is zero, the lamp stops emitting light, except maybe a tiny bit from the hot electrodes. I think you're confusing them with fluorescent lamps, which have a phosphor and persistence.

Sodium lights do produce some flicker, but not much, because the lamp conducts most of the time.

LED lights aren't always better for the environment, than sodium lamps. The broadband emission is more similar to moonlight so can have a negative impact on wild life, such as turtles nesting on beaches, where the offspring can be confused and go towards the city, rather than out to sea. Sodium lamps have a narrowband output in the yellow region, which is more turtle friendly. Of course it's possible to use yellow LEDs, but they aren't as efficient as sodium lamps, which incidentally are actually more efficient than LEDs, at higher light intensities, although they have poorer colour rendering and lower efficiency when it's darker, hence why they're now being used for street lighting.
 
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Offline treez

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Re: Small UK owned streetlight design company cannot design own LED drivers?
« Reply #10 on: August 05, 2018, 10:52:41 am »
Thanks...
The point of Chinese imports of  electronics  products into the UK is a point of concern for  small UK electronics engineering companies. Many of them are masquerading as electronics engineering companies, (with a token group of British made products ….etc etc). As such, they are more easily able to act as “middle-men” for large quantities of Chinese electronics into the UK and beyond.

The EU has recognised that this  has  actually  been going on throughout Europe….and so the EU is literally closing down ports on the European mainland so that   there are fewer conduits through which Chinese imports can get into the EU without being detected by EU customs. The remaining few ports are tightly regulated by  EU customs so that all Chinese imports are registered, and exposed to the tariff system of the EU. British ports, up until now, have been free of this regulation of  UK ports, so Chinese imports can even get in  to UK without EU customs knowing. Suffice to say that nobody in UK actually wants UK companies to pay tariffs into the EU central bank anyway. What would be the point of that? None.

The EU has even arranged a rail ink direct from China into the EU…It has a few stations which again , the EU has tightly regulated with its customs officials. Trains are convenient because they can’t swerve off the tracks and avoid the customs officials.
The point is that UK is totally flat broke….2 trillion in National Debt……and UK has sold off most of the industry needed to pay off the debt…..so after brexit, the UK government will tariff high heck out of Chinese imports  into UK, and will enforce this from within UK…this will result in a lot of  small UK “electronics companies” going straight out of business....
....because their lucrative Chinese import middle-man business will be smashed.
« Last Edit: August 05, 2018, 10:55:05 am by treez »
 

Offline treez

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Re: Small UK owned streetlight design company cannot design own LED drivers?
« Reply #11 on: August 05, 2018, 10:57:46 am »
Quote
Why would there be any persistence in a sodium discharge lamp?
Thanks, i just notice that when they are switched off, they seem to still be shining on for a while, before eventually dwindling out
 

Offline bob225

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Re: Small UK owned streetlight design company cannot design own LED drivers?
« Reply #12 on: August 05, 2018, 01:02:18 pm »
this will result in a lot of  small UK “electronics companies” going straight out of business....
....because their lucrative Chinese import middle-man business will be smashed.


Your 20-30 years late, electronics is a very niche market compare to what it was back in the 90's most of the manufacturing and skills base has gone to Asia, its uneconomic to repair electronics as the cost is usually 40-90% of a newer comparable product (retail type electronics)

I can get a prototype PCB manufactured in china for a 10th of the cost of a uk suppler, I can even have it built in china for a 1/5 of the cost


Margins are so tight in the uk, Especially in pc building you need to turn over 8-10 machines a week to put food on the table
 
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Offline treez

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Re: Small UK owned streetlight design company cannot design own LED drivers?
« Reply #13 on: August 05, 2018, 01:44:25 pm »
Bob225 I Agree entirely with what you say...and if you read my posts above, you will see that i agree with what you say.
The situation is, that the "middle men" companies  of UK will be heavily tariffed by the uk government after brexit..this will smash them.
These middle men companies exist entirely for the import of chinese goods into UK..
 

Offline janoc

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Re: Small UK owned streetlight design company cannot design own LED drivers?
« Reply #14 on: August 05, 2018, 01:46:33 pm »
so after brexit, the UK government will tariff high heck out of Chinese imports  into UK, and will enforce this from within UK…this will result in a lot of  small UK “electronics companies” going straight out of business....
....because their lucrative Chinese import middle-man business will be smashed.

Seriously  :-DD just  :palm:

And you think that the good serious UK companies will spring up overnight to replace all those now heavily taxed goods that your economy actually relies on. And will be able to replace them at the same costs as you were used to, right? Not at all jacking up prices when there is no competition (and also because manufacturing costs in UK are 10x  higher than the Asian ones).

Good luck explaining to the UK consumers why a new iPhone costs 50% more in the UK than across the border in Ireland or France (if you think Apple or others will suddenly move their manufacturing to UK to avoid tariffs you have to be smoking crack). If your government actually does this, great - a perfect example how to commit a political suicide.

Seriously ...  :palm:
 
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Offline tggzzz

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Re: Small UK owned streetlight design company cannot design own LED drivers?
« Reply #15 on: August 05, 2018, 02:51:57 pm »
I wondered how long it would be before someone picked up on treez' arguably political statement, and mutated the thread in to a political Brexit discussion.

I avoided commenting in treez' statement for just that reason.

Yes, that is a hint.
There are lies, damned lies, statistics - and ADC/DAC specs.
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Online Zero999

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Re: Small UK owned streetlight design company cannot design own LED drivers?
« Reply #16 on: August 05, 2018, 03:57:36 pm »
so after brexit, the UK government will tariff high heck out of Chinese imports  into UK, and will enforce this from within UK…this will result in a lot of  small UK “electronics companies” going straight out of business....
....because their lucrative Chinese import middle-man business will be smashed.

Seriously  :-DD just  :palm:

And you think that the good serious UK companies will spring up overnight to replace all those now heavily taxed goods that your economy actually relies on. And will be able to replace them at the same costs as you were used to, right? Not at all jacking up prices when there is no competition (and also because manufacturing costs in UK are 10x  higher than the Asian ones).

Good luck explaining to the UK consumers why a new iPhone costs 50% more in the UK than across the border in Ireland or France (if you think Apple or others will suddenly move their manufacturing to UK to avoid tariffs you have to be smoking crack). If your government actually does this, great - a perfect example how to commit a political suicide.

Seriously ...  :palm:
Yes, that's why electronics are low cost commodity items today. Just look at the prices of TVs back in the 60s, compared to averages back then!

There is an argument for making electronics more expensive, to cut down on waste for the sake of the environment, but it's a totally different one, than that made by those who want to bring back manufacturing jobs.


Quote
Why would there be any persistence in a sodium discharge lamp?
Thanks, i just notice that when they are switched off, they seem to still be shining on for a while, before eventually dwindling out
What sort of sodium lamps are those? Low pressure or high pressure?

It's most likely due to incandescence and the persistence of the image on your retina could also explain it.

Unless there's some new hybrid sodium-fluorescent technology I'm not aware of, sodium lamps do not use phosphors.
https://en.wikipedia.org/wiki/Sodium-vapor_lamp
 
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Offline doobedoobedo

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Re: Small UK owned streetlight design company cannot design own LED drivers?
« Reply #17 on: August 05, 2018, 05:20:04 pm »
Treez likes to pretend he's British, and knows about the UK. I personally think that everything he says is made up. I very much doubt if he's ever been here or even knows anyone here.
I'm sure he'll like this post too.
 
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Offline IanB

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Re: Small UK owned streetlight design company cannot design own LED drivers?
« Reply #18 on: August 05, 2018, 05:20:48 pm »
Why would there be any persistence in a sodium discharge lamp?

Because, hypothetically, it could act like a capacitor, or charge storage device, and the electric field in the tube may take time to discharge?

Because, hypothetically, the electrons surrounding the sodium atoms that have been raised to a higher potential by the electric field may take time to decay back to the ground state (there may be a time constant for that decay).

I do not know the physics, and the above hypotheses may be wrong, but I do not see a basis for simply ignoring the possibility without evidence to the contrary.
I'm not an EE--what am I doing here?
 
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Offline IanB

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Re: Small UK owned streetlight design company cannot design own LED drivers?
« Reply #19 on: August 05, 2018, 05:28:36 pm »
the EU is literally closing down ports on the European mainland so that   there are fewer conduits through which Chinese imports can get into the EU without being detected by EU customs. The remaining few ports are tightly regulated by  EU customs so that all Chinese imports are registered, and exposed to the tariff system of the EU. British ports, up until now, have been free of this regulation of  UK ports, so Chinese imports can even get in  to UK without EU customs knowing. Suffice to say that nobody in UK actually wants UK companies to pay tariffs into the EU central bank anyway.

You realize that this reads like total bullshit, right? That it fails to recognize the reality of the trade, legislative and fiscal environment within the EU? That there is no such governmental entity as "The EU" capable of doing the things you suggest it is doing? And even if there were, the UK is inside the EU so such actions would apply just as much to the UK as to Germany, France or the Netherlands?
I'm not an EE--what am I doing here?
 
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Offline amyk

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Re: Small UK owned streetlight design company cannot design own LED drivers?
« Reply #20 on: August 05, 2018, 05:43:56 pm »
One way to make flicker less perceptible is to increase the frequency into the kHz range. That also means smaller capacitors, and as such you might not need electrolytics.
 
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Offline IanB

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Re: Small UK owned streetlight design company cannot design own LED drivers?
« Reply #21 on: August 05, 2018, 05:47:59 pm »
I think flicker is potentially very significant with moving objects like vehicles. Has anyone seen cars with LED tail lights that flicker like crazy when the car is moving? It drives you nuts. Imagine if that happened to every car driving under street lights?
I'm not an EE--what am I doing here?
 
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Online Zero999

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Re: Small UK owned streetlight design company cannot design own LED drivers?
« Reply #22 on: August 05, 2018, 05:54:25 pm »
Why would there be any persistence in a sodium discharge lamp?

Because, hypothetically, it could act like a capacitor, or charge storage device, and the electric field in the tube may take time to discharge?

Because, hypothetically, the electrons surrounding the sodium atoms that have been raised to a higher potential by the electric field may take time to decay back to the ground state (there may be a time constant for that decay).

I do not know the physics, and the above hypotheses may be wrong, but I do not see a basis for simply ignoring the possibility without evidence to the contrary.
Well if you read the rest of what I wrote, I didn't say it's impossible for a sodium lamp to emit any light, after the power has been removed.

By the way, neither of the theories you've proposed, seem to be plausible. The capacitance between the electrodes will be tiny and the electrons in the plasma return to their ground state fairly rapidly. If you look at a mains powered neon lamp, the flicker can be clearly seen. The flicker from sodium lamps is less noticeable but I've seen some stroboscopic effects, in a car driving under sodium lamps. One thing I've noticed is the bars on a metal railing often become visible, despite travelling faster than the blur point.

One way to make flicker less perceptible is to increase the frequency into the kHz range. That also means smaller capacitors, and as such you might not need electrolytics.
The trouble is, if the lamp is running off a mains supply, there will be 100Hz ripple on the DC bus, which needs to be removed with a large capacitor, before the high frequency driver.
 
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Online Gyro

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Re: Small UK owned streetlight design company cannot design own LED drivers?
« Reply #23 on: August 05, 2018, 06:00:31 pm »
I think flicker is potentially very significant with moving objects like vehicles. Has anyone seen cars with LED tail lights that flicker like crazy when the car is moving? It drives you nuts. Imagine if that happened to every car driving under street lights?

I thought I was the only one who got wound up by flickering tail lights!
Chris

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Offline treez

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Re: Small UK owned streetlight design company cannot design own LED drivers?
« Reply #24 on: August 05, 2018, 06:37:44 pm »
Thanks, yes and i agree with your sentiments...the point is that post brexit, being a middle man (for chinese imports into UK and beyond) will not be nearly so lucrative as it is now. (due to uk government tariffing the heck out of it)
...the middle man mark-up will not be anywhere near as good.
Hence a lot of companies will disappear.
 


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