LED ligth(ning) on 240V no trafo

S

Super_voip

New Member

• Oct 6, 2009

• #21

audioguru, I have seen alot of the early LED traffic lights with blown strings. So they don't last forever. the period between changes is greater.

 

audioguru

Well-Known Member

Most Helpful Member

• Oct 6, 2009

• #22

The LED traffic lights in Canada don't use cheap Chinese LEDs from E-Bay.
They use high quality LEDs that so far do not burn out.

I bought some cheap LEDs from India. 5 out of 10 were defective.
I have Chinese LED products that have all failed.
I think every Chinese product fails soon.

 

C

case-sensitive

Member

• Oct 6, 2009

• #23

your LEDs are made in China anyway and re labled somewhere. Got some chips from Malaysia, Indonesie, and some Mexico (can't remember the last one for sure)

 

audioguru

Well-Known Member

Most Helpful Member

• Oct 7, 2009

• #24

case-sensitive said:

your LEDs are made in China anyway and re labled somewhere.

Click to expand...

No.
Lumileds (Luxeon) are made by Philips in Malaysia. They are not cheap Chinese junk.

 

C

case-sensitive

Member

• Oct 7, 2009

• #25

Malaysia any better?

Suppose the LED light fittings in the shops are Chinese as well, still they are claiming they last longer than CFLs (suppose CFLs are made in China as well)

But what about the schematics I posted 5 posts up, are they ok like that?

 

Last edited: Oct 7, 2009

audioguru

Well-Known Member

Most Helpful Member

• Oct 7, 2009

• #26

Philips don't buy cheap Chinese junk. They make very good and reliable LEDs in their own factory in Malaysia.
The cheap Chinese E-Bay ones are No-Name-Brand (made in somebody's basement) without any reliability and no quality control.

You posted PDF files that I did not bother to open. You should have posted PNG files that open by themselves.

 

C

case-sensitive

Member

• Oct 8, 2009

• #27

there you go. Pngs this time.

Did simulation with 76 LEDs, set their properties to 11mA and Vf 3.1V instead 5mA/1.66V.
The other simulation is LEDs replaced as resistor, aiming at 2.3V (would be 3.1 V/sqrt 2)?
The other is just the bit of data sheet with a graph current over voltage, so you could determine resistance at a certain voltage.

 

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