You can probably find strips for the half the price Shopjimmy charges from Chinese sellers. They could be originals, poor quality substitutes or good quality substitutes. I had issues with Rzconne branded strips so best to avoid those.
This is the first LED TV I've ever really taken a crack at....so I'm just ASSuming that all these LED's are in a series (I haven't disassembled the panel yet)....and like old school christmas tree lights, if one goes open, the whole string goes dark?
This is the first LED TV I've ever really taken a crack at....so I'm just ASSuming that all these LED's are in a series (I haven't disassembled the panel yet)....and like old school christmas tree lights, if one goes open, the whole string goes dark?
This model is know for bad backlights (Insignias, RCA/Proscan/Haier, LG LN LA and LB, Samsung E, F, H, J, N model years). The LED driver circuitry can detect a shorted LED and shut them down leaving the TV still on so you can perform the flashlight test to see if you have video. Symptom is usually a quick flash of the backlights when turned on. If the LED fails open, the backlights won't flash. Samsung don't have protection so you end up with a lot of bad LEDs.
This model is know for bad backlights (Insignias, RCA/Proscan/Haier, LG LN LA and LB, Samsung E, F, H, J, N model years). The LED driver circuitry can detect a shorted LED and shut them down leaving the TV still on so you can perform the flashlight test to see if you have video. Symptom is usually a quick flash of the backlights when turned on. If the LED fails open, the backlights won't flash. Samsung don't have protection so you end up with a lot of bad LEDs.
As mentioned on page 1, its not shutting down, the driver out has ~340v present.....but no lights. FLashlight trick shows image (test pattern).
Does anyone know how Hisense/Insigna datecodes breakdown? This set is "14D10A".... What is the breakdown for this?
I ordered some strips for this set. Being a freebie, it was worth the $40 gamble, the set came from a clean home....its in mint condition with remote that's not worn & grimy.
I don't have that model but an earlier version. They are a good indicator for testing leds. If the strips have an equal number of led in them then you would expect to see the same voltage for each strip. If lower, it could be an indication of shorted led(s).
The only problem with them is that they supply a much lower current than the leds normally receive. A faulty led could at low current appear to be OK but fail when driven at a much higher current.
They are however a useful tool to have.
Edit.
Just had another look at the specs of the one you refer to and the much higher current of 150mA makes it much more useful than mine which outputs a maximum of 50mA
With LED TVs, I find around 80% of failures tend to be backlights mostly caused by being driven at the maximum spec. Getting a higher current LED tester is better but a basic one is good for basic troubleshooting. I use my LED tester more than my multimeter.
I contact those seller and ask them to clarify the current rating but all of them just tell me to read the description.
This is my believe.
The 150mA does not show power it can deliver, 300V @150mA = 45W.
If you look at the spec of 1A, it shows power of 30W = 3V LED * 1A, or 200V @150mA.
No way the size of the test can do 300V @1A (300W, that will be huge power supply).
The one rated at 1A should be able to deliver 300v @100mA, or 200V @150mA which will be 30W.
The one that I have can do 30mA at 300V = 9W, so the one with 1A that claims 3 times the power is what they are claiming.
I think Vince bought one of these high current one so I ask him to perform the test when he gets it.
1A description:
Currently, this function (2019 06) has no similar products on the market, the power is three times higher than that of similar products on the market, the long-term working power reaches 30W and the maximum power is 36W At higher electrical current, the tested light bar voltage value is closer to the current operating voltage of the constant current plate. (The current of similar products on the market is only 30 mA, the power is not enough, the high and low voltage gears cannot be changed and the transformer is much smaller)
So the 1A version, if the spec is true, then it will be useful up to 200V @150mA, better than the 30mA LED tester.
I had a RCA SRC5565 that kept blowing LEDs on the same strip even with the backlight reduced to 10/100 in the service menu. I was using 1.5W LED modules initially but was running low so replaced the whole strip with 1W. I ended up ordering 2W ones and replaced the entire strip a second time. I got a RCA with the same panel and replaced the one bad LED with a 2W and turned the backlight down to 20/100. A LED on a different strip had burnt out 2 days later. With 2.7V LEDs 1W=370mA, 1.5W=550mA and 2W=740mA. There is a setting in the service menu to adjust the PWM current but it didn't save when I set it lower.
The strips came in yesterday....so today's task was installing them. I won't go into the disassembly & reassembly ordeal or post all the pics I took, as this would be nothing new for you seasoned TV techs (albeit this was my first surgery of this kind on a LED TV).
In the end, it was a success.
The culprits....not sure which is bad...I replaced them all. I did order one of those LED strip testers, I'll play around with it with these strips when it gets here.
FWIW, I narrowed down the bad strip. Using my bench supply with no current limiting, turned all the way to zero volts with my ammeter in series, I slowly increased voltage until ~150mA was reached on the ammeter....which it appeared to have the LED's fully illuminated. I didn't drive them any harder than that, I didn't want to cook the good ones, I can see some practical uses for these. @ 150mA, the voltage was ~+17v. The 3rd strip I tested failed to light (open)...the other 9 were good and consistent with eachother on power consumption.
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