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20W LED tube interchangeable with 20W fluorescent tube.

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grizedale

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Hello,

We want to put a 20W LED tube into a socket for a fluorescent tube with a high frequency, switch mode fluorescent ballast driver.

...we dont want to remove the fluorescent ballast as it would be inconvenient.

Are there any standard solutions for this?

-we still want it to be quite efficient, so dont want a linear driver to be added in for the LED current control...we want efficient switch mode current control of the LED current.


...Ultimately, we would like to design a 20W LED tube (containing auxiliary circuitry and converter , etc) which could run off ANY fluorescent ballast.
..that is, it should be able to run off either a 50Hz magnetic ballast, or any high frequency switch mode fluorescent ballast.

....do you know if standard solutions exist for this?
 

I guess you must remove ballast and starter....
**broken link removed**
 

Hi, Thanks, unfortunately i can't say too much as i signed a NDA.

I can say that ripping out the fluorescent ballast is not convenient in this situation......it would be too expensive in this particular application.......

-not only that...but the customer doesnt really know if they want LED.......they'd like to try it , and if they dont like it, they'll go back to their fluorescents....so another reason to leave the fluorescent ballast in.
 

I guess LED tubes are too expensive now and 30 000 - 100 000 hours of work time .... This is not true We are use LED lights so ... and after few months ... 10% of LED become bad.
 

...the thing is the customer wants a shade of LED light that isnt achievable with fluorescent tubes.....so we need to use LED tubes.
 
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So you're saying the ballasts aren't built into each tube?

You'd have to describe the ballast circuit for me to be sure, but most ballasts really won't do anything without a resonant load on them. So I don't see a good way to do it by using the normal ballast connections. However if you're allowed to rewire the ballasts a bit you could change the connections to just give the DC output of the bridge rectifier, and use that for your own ballasts which converts that DC voltage to drive the LEDs.
 

In some cases the ballasts are outside the tube fitting.

.......Basically, our sales people are telling us that the customer specifically doesnt want to remove or interfere with the fluorescent ballast in any way........so all we have is the actual fitting for the fluorescent tube itself......and we must put the new LED tube in there....and it must sucessfully run off the fluorescent ballast.

I am not sure why our sales people are entertaining the customers idea to keep the fluorescent ballasts.

It sounds like madness....?...do you agree?

Or does this kind of think happen somewhere?

....LED tubes running off fluorescent ballasts.
 

Maybe it's possible to just replace the ballast with a bridge rectifier and get back a DC voltage...? It might still oscillate and deliver power. Maybe have step down transformer so that you get something reasonable like 100V instead of 600V or whatever.

But in that case you still end up with an unregulated DC voltage, so you still need to build your own DC-DC converter, which will have losses on top of the losses from the first ballast. You're not going to get great efficiency.
 
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....yes i agree about the low efficiency.

.......I am sorry but there really is a need to run the LED tube straight off the fluorescent ballast.

Is this as crazy as i think it is?
 
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For running off of high frequency ballasts, it sounds pretty dumb. Doesn't mean you can't make them happy though, if they're willing to pay.... Have they actually given a desired efficiency spec, like in lumens per watt or something?
 
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i think they just want to see what kind of efficiency we can come up with, and then theyll muse over it and see if thats ok.
 
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Well, somebody's doing it already......(Driving an LED tube from a fluorescent ballast driver).......

**broken link removed**

.....I cannot understand how they are managing to sell these.
-if they can sell these then they can sell ice to Eskimo's.

No matter what the EverLED-TR is like, it can never be anywhere near as good as a LED tube with matching LED Driver..
..i notice in the instruction manual pdf doc, they ask customers to report "unusual operation" to them..
..if the overall product catches fire....who is liable i wonder?.....is it the fluorescent ballast manufacturer, or EverLED?...
.I think i'm now going to go away and find a machine that converts beer into brandy....somebody must be doing that somewhere too.
 

Hello,

I am still trying to discover if this product, the EverLED-VE LED light tube, has passed UL or CE approval, or in fact, has it passed any approvals tests such as Safety and EMC related?

**broken link removed**

(as mentioned in previous threads, its a LED tube which runs off literally any kind of fluorescent ballast)

I have written to EverLED about this but get no reply.
There is no evidence of any approvals on the website.
 

Just buy a couple and break them open. I'd be really curious to see how they work.

edit: their claim of 80lm/W is pretty dubious. Or they're using lots of fancy, small, high efficiency LEDs. And they certainly don't account for any inefficiencies in the preexisting ballast. That's understandable, since they have no way of knowing what your ballast is like, but it means that overall efficiency from the user perspective will be significantly lower.
 
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i'd like to but some but there $79 plus shipping to UK.

They done have European distributors and i wonder if its legal to actually ship these into UK at all(?)
 

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