Vizio 47 vo47l power supply DPS-433BP

[sheen818]

in left lower side, C241(below arrow) is 470uf, 35v, always blow out after replace it. I know some components are bad. no idea which? Hope someone help me. after blowing out, tv is still working normal. I have some tech skills, but need to learn a lot. Thanks.

[budm]

Re: Vizio 47 vo47l power supply DPS-433BP

"in left lower side, C241(below arrow) is 470uf, 35v, always blow out after replace it." What exactly do you mean by 'BLOW OUT'? The top just exploded? Cap is installed with correct polarity?

[CapLeaker]

Re: Vizio 47 vo47l power supply DPS-433BP

can you make another picture from the other side of the board? Those caps have to be installed correctly, other than that, they will blow, as budm already mentioned. With the cap removed, maybe put your DMM in DC and see how much voltage is there where the + and - of the caps go.

[sheen818]

Re: Vizio 47 vo47l power supply DPS-433BP

please check pictures, thanks.

[sheen818]

Re: Vizio 47 vo47l power supply DPS-433BP

I can install caps correctly and measure some components around the cap, don't find bad parts. I only measure them with ohm, don't find short or open parts. I had already replaced all caps in this area. plug in power in a min, it burnt with fume and big sound immediately. Thanks.

[budm]

Re: Vizio 47 vo47l power supply DPS-433BP

I can see that the cap C241 is installed correctly, so the new one has domed top and blow up after a minute, I would would expect the other 4 caps (C240A~C, 1000uF 35V) caps to be damaged too if the Voltage had gone up way pass 35VDC since these 3 caps are part of the Pi filter.
Can you verify the Voltage on the caps to see what it is?
Notes: now I see that the pictures show the original caps not the new caps in place.

[ljintexas]

Re: Vizio 47 vo47l power supply DPS-433BP

use 470 by 50 volt cap

[budm]

Re: Vizio 47 vo47l power supply DPS-433BP

But what DCV do you get when you measure it? Also the pictures show the original cap (470uF 35V) in place, how about the picture that show the new cap in place?
"I can install caps correctly and measure some components " So did you install the new cap? You did not say " I did install the caps correctly"
BTW, did you also use low ESR type not general purpose caps, right?

[budm]

Re: Vizio 47 vo47l power supply DPS-433BP

use 470 by 50 volt cap

????

[CapLeaker]

Re: Vizio 47 vo47l power supply DPS-433BP

Cording to the pics, the cap is installed correctly. So what voltage do you get on CN2 with the 24V pins to SGND? That's where the blown cap is in between those points. May be worth looking with an oscilloscope to see the ripple on it.

[sheen818]

Re: Vizio 47 vo47l power supply DPS-433BP

no, these pictures are new caps.

[sheen818]

Re: Vizio 47 vo47l power supply DPS-433BP

pictures show new caps. I bought these caps on ebay and my ESR-micro v4.0s meter is broken, and no way to measure ESR. The seller don't know if it is low esr. I am looking for esr meter now, how about "DER EE DE-5000 Handheld LCR Meter"

But what DCV do you get when you measure it? Also the pictures show the original cap (470uF 35V) in place, how about the picture that show the new cap in place?
"I can install caps correctly and measure some components " So did you install the new cap? You did not say " I did install the caps correctly"
BTW, did you also use low ESR type not general purpose caps, right?

[sheen818]

Re: Vizio 47 vo47l power supply DPS-433BP

I only measure components when the board is no charge. I never measure DC because I am afraid to get hurt. how to do that? Thanks.

Cording to the pics, the cap is installed correctly. So what voltage do you get on CN2 with the 24V pins to SGND? That's where the blown cap is in between those points. May be worth looking with an oscilloscope to see the ripple on it.

[sheen818]

Re: Vizio 47 vo47l power supply DPS-433BP

I fixed my esr-micro meter. Then I remove 5 caps (C240A~D, 1000uF 35V) and C242(50v, 2.2uf) caps from board, C240, all of them got 0.06 ohem esr and around 1050uf, should be good. C242, 4.7ohem, 2.5uf, is good too. Decide to try again. For C241, I have 35v, 240uf, 85oC, 0.09 esr, and 470uf, 35v, 105oC, 0.11 esr(installed it last time). Which better? Thanks.

[budm]

Re: Vizio 47 vo47l power supply DPS-433BP

I only measure components when the board is no charge. I never measure DC because I am afraid to get hurt. how to do that? Thanks.

Just put the meter probes to the two legs of C240A and check the DC Voltage top see if it is more than 35V, then do the same on the cap that keeps blowing up.

[CapLeaker]

Re: Vizio 47 vo47l power supply DPS-433BP

I only measure components when the board is no charge. I never measure DC because I am afraid to get hurt. how to do that? Thanks.

I wouldn't be afraid to work on the cold section of the power supply. Where you would get hurt, that would be in the hot section. There can be 400v dc and that will go with a bang!

[sheen818]

Re: Vizio 47 vo47l power supply DPS-433BP

all of the caps(C240A-D, C241) are 24.01V or 24.02V. I replace C241 with 50V, 470uf. TV is working now a few hours, now is ready to blow out. voltage is ok, I think if current is problem? Thanks.

Just put the meter probes to the two legs of C240A and check the DC Voltage top see if it is more than 35V, then do the same on the cap that keeps blowing up.

[CapLeaker]

Re: Vizio 47 vo47l power supply DPS-433BP

Is that a Rubycon XYA series? Coming off ebay I wonder if it is a fake. Does the cap get hot? Did you check the ripple on that cap with and oscilloscope?

[sheen818]

Re: Vizio 47 vo47l power supply DPS-433BP

I bought this 470uf, 50V from local store. it's esr is 016. maybe half an hour, it bulged. replaced with another esr 0.09, 470uf, 35v cap, in 30 seconds, it bulged. only this cap bulged, no others, and voltage is 24v. why it bulged again, again? I think it bulged so fastly, should not be because of esr, it is something else. yes, the cap got very hot. sorry, I don't have oscilloscope, only have multimeter and esr meter.

Is that a Rubycon XYA series? Coming off ebay I wonder if it is a fake. Does the cap get hot? Did you check the ripple on that cap with and oscilloscope?

[CapLeaker]

Re: Vizio 47 vo47l power supply DPS-433BP

Did you replace the 24V rail filter caps? If you have a true RMS DMM, you could try to measure the AC component on that cap that wants to blow up all the time. If your meter is not true RMS, try to put a series cap on there. Other than that, I am running out of ideas.