Samsung plasma pn50a550s1fxza

[flocko]

Re: Samsung plasma pn50a550s1fxza

And when you first ground you hear the relay click in? do you hear it click out again or does it come in and stay in . have you checked all the fuses are good

[audiodreamer]

Re: Samsung plasma pn50a550s1fxza

There appears to be two relays on board. One seems to be doing anything. It clicks in and stays. There also appears to be three fuses. They all check good.

Maybe I am not checking the right places for these voltages although I was checking just like the standby voltage.

At upper and lower fuse I have no voltage. At the middle fuse there is 167 volts.

[flocko]

Re: Samsung plasma pn50a550s1fxza

You can recheck the voltages, just above the jump we are connected to, you will see a white socket with three pins 5.3v ground and Ve use chassis as ground (black lead set to Dc volts ) test to see if you have them?

[audiodreamer]

Re: Samsung plasma pn50a550s1fxza

That is a big negative. No voltage.

[flocko]

Re: Samsung plasma pn50a550s1fxza

Hi just read all your posts again, and want you to check the soldering on the relays, I missed the fact that you say you think only one is clicking?I hope this is were the problem is? as having no output voltages with no blown fuses or anything that looks burnt would not ring true. Just one other thing when you check voltages on the hot (primary) side you use the neg- legs of the big main caps as ground and test in DCv There are no service manuals for this board the nearest one to it is the BN44-00237A . so please look that up, you will find manuals on here

[audiodreamer]

Re: Samsung plasma pn50a550s1fxza

I have to ask. When you say primary voltage I think my incoming line voltage of 120. Is this incorrect? I see two larger brown caps on left side of board is this what you are referring to?

So to make sure I would check the right place from which points do I need to check for voltage? And I am checking for dc volts not ac volts.

Can you tell me what voltage should be present at the relay that I think is not working and when does it activate? Will it be active when the jumper is applied?

I am trying to think of good questions that will help you help me troubleshoot this board.
If I happen to get this going you people are truly genious to do this blind.

Mike

[flocko]

Re: Samsung plasma pn50a550s1fxza

Yes any voltages taken on the primary (hot ) side on or after the large main caps are to be read in DCv,did you look for the manual for the BN44-00237A? this will help you understand why i think your problem is with the non acting relay. as you need both working to feed the power to the rest to the hot side of the board ? you have the feed that taps off for the stby and you have one relay click when grounding PSon, but to get the rest of the power board to come to life you need both relays working, I hope this is helping you? re-flow the solder to the relays and then see if you have the board working again Flocko

[audiodreamer]

Re: Samsung plasma pn50a550s1fxza

Is there in chance you could point me in the direction of that manual?
Thanks Mike

[flocko]

Re: Samsung plasma pn50a550s1fxza

Hi Mike go to the tv repair ref library in the troubleshooting tv and videos go down to tom66 first post there you will see a link for free service manuals, click on that

[audiodreamer]

Re: Samsung plasma pn50a550s1fxza

After rechecking both relays appear to be working.

Back to the fuses. One is incoming power of 120 volts. checks good. One in the middle of the board labeled FS801 T2AH/250V, it has 167 v at it. The one at the top is labeled FB803 T5AH/250V, it has no voltage at it. Should it?

[flocko]

Re: Samsung plasma pn50a550s1fxza

do we have a problem with the relays? How are you testing FS801 (you want volts DC Hot side of board. test this how you were told ) are you getting the same reading both sides of the fuse?, what Dc voltage are you seeing across the big cap with relays in ?

[audiodreamer]

Re: Samsung plasma pn50a550s1fxza

Both capacitors have what looks like 393 volts. FS801 voltage was both sides of fuse to chassis ground.

[flocko]

Re: Samsung plasma pn50a550s1fxza

You have PFC on the main caps 393v so the that is working ? you are still not testing right? you only use the chassis ground on the cold side? so check the fuse FS801 again but do it the correct way using the -neg leg of the main cap? tell us what you have on both sides in Dc volts. i can only help if you give me the right info from your testing This is why I think nobody from your side of the pond has come to your assistance and you are left hanging?

[saaber]

Re: Samsung plasma pn50a550s1fxza

Hello and good morning! I hope these pictures are ok. If there arany that need to be retaken or from different vantage point please let me know. I hope I got what would seem important.

Thanks for everyone's time

Mike G

Yes I agree
See my answer on this site, but I also have to change your language !
http://upsonline.ir/

[audiodreamer]

Re: Samsung plasma pn50a550s1fxza

You have PFC on the main caps 393v so the that is working ? you are still not testing right? you only use the chassis ground on the cold side? so check the fuse FS801 again but do it the correct way using the -neg leg of the main cap? tell us what you have on both sides in Dc volts. i can only help if you give me the right info from your testing This is why I think nobody from your side of the pond has come to your assistance and you are left hanging?

My apologies! I read that but it did not register until now.

[audiodreamer]

Re: Samsung plasma pn50a550s1fxza

Truth be told I had misread about checking voltage to negative of big caps. I was reading it as check voltage on the caps not using the negative to check all voltages on hot side of board.

[flocko]

Re: Samsung plasma pn50a550s1fxza

You were asked to take the voltage across the main you gave me that 393v and that tells me the PFC is working, now I need to know what you have on both sides of the fuse FS801? but taken correctly

[audiodreamer]

Re: Samsung plasma pn50a550s1fxza

Both fuses at this time check 393 volts on both sides.

Before I knew not to use chassis as negative for checking voltage on hot side of board I was probing at different locations on board and had what appeared to be a short (sparks jumping to test lead).

Yesterday morning on cold side of board I had 5.3 volts not on stby terminal. That was not there before. So I plugged all boards in as they should be. I am not sure why but at this time my continuously clicking relay has stopped. Have not had the chance to check any further.

Whatever it is probably just a fluke and temporary.

[flocko]

Re: Samsung plasma pn50a550s1fxza

Check the back of the board, closely inspect the soldering for signs of cracking you would not be the first or last to find it ? re-flow all the big heat sink components + transformers + relays and the like with new solder, then recheck for the output voltages on the board (cold side use chassis as ground DCv) if you get all apart from the Vs you will need a resistor 470-1000 ohms to short VSon to 5.3v To bring the VS to life