How long should an LED strip light last?

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GLS

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Just over a year ago I bought a 4' LED strip light batten to replace the old bulb type. Today about a quarter of the batten is dark and the rest refuses to light up fully. Is the thing now dead, as there doesn’t appear to be anything like a starter or replaceable parts that I can see. The LEDs appear to be a sealed unit.
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Most LED light units are sealed and cannot be repaired plus many do not last as long as the OEM will claim. I have had LED bulbs that have only lasted a year before either going dead or just flickering and this makes them an expensive option. I suppose when we had a tungsten filament in a partial vacuum there was little to go wrong and we accepted they will fail but LED bulbs have electronic's to drive the LED's and therefore more component parts that can fail.
 
There will probably be a 230V-12V psu inside the tube. I would say the LED's are in series and the first "dead" one has failed. You could try bypassing it and the rest of the LED's should work.

As usual the 30,000 hrs or whatever is bulls**t in a lot of cases.
 
Your need to understand the theory of LED's, in simplistic terms they are just a PN semiconductor junction and are current driven not voltage so any PSU will be current regulated and not voltage regulated. In the most basic form you can just use a simple resistor in series with the LED to control how much current flows, known as the forward current. The issue is that we have Ac at 230 volts which is not an issue but ideally it needs to be smooth Dc and more precise current control all in a small form factor.
 
This is typical of 'cheap' LED Luminaires. (if it was 😁) They tend to have pretty crude drivers and use LEDs with wide range parameters. This means that the some of the LEDs may be over-driven and fail early. They use parallel arrays of series diodes and current control may not be very good, especially under mains fluctuations/temperature variations etc They also push the diodes to the edge of spec to get the brightness. Basically rubbish design.

I use Philips. They seem to last reasonably well apart from when they are hit hit with a large piece of wood.
Once they fail, they are a throw away item, unless you do what I do and cut up the LED strip and use as 12V bulbs.
this is the driver from the Philips tube I broke.

IMG_6280.JPG


that is a good driver. (UL recognised)
Mains rectified, then DC-DC converter to produce a controlled current at the strip. All the control is on the bottom side

This is a cheap LED lamp.
IMG_6281.JPG


And the driver circuit:-

LED driver.JPG



Basically a bridge rectifier and the current control chip PT4515C with the control resistor
 
The ones I have in my work shop have been in over 5 years and still work as they should(y) Now i just hope that I have not jinxed myself:eek:
 
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