Panasonic 50" VT20 arcing at edge of panel to frame

[tw2005]

Re: Panasonic 50" VT20 arcing at edge of panel to frame

That should be possible I suppose although if there is a build up of charge and no metal to zap to would it zap my ear when I'm listening for the spark?

I've got the V20, same bezel which is metal but std FHD panel. No issues yet at 17000hr, I can't get my head around how suddenly it just starts doing it. Dust or debris is the obvious thought.

You say you've cleaned it all. The image of the ribbon at the SS board to panel though looks a little weird like dust or something underneath it. Rust is visible on the metal plate and marks on the board.

has it ever been wet? And you've owned this from brand new?

For manuals you could try TC-P54VT25, bigger but should be same construction and engineering .

Are you in SE Q

[infrag]

Re: Panasonic 50" VT20 arcing at edge of panel to frame

yep, that's normal. It remains armed , if you hit the remote it'll fire up quicker with no relay latch as it is already latched but as you say if it does does get a command to turn on after that time you 'll here the relay de-energise.

Ever heard the relay latch and delatch at weird times through the night without touching anything?

No never as it always gets switched off at the wall by us after we wait for it to go into standby mode.

[infrag]

Re: Panasonic 50" VT20 arcing at edge of panel to frame

I've got the V20, same bezel which is metal but std FHD panel. No issues yet at 17000hr, I can't get my head around how suddenly it just starts doing it. Dust or debris is the obvious thought.

You say you've cleaned it all. The image of the ribbon at the SS board to panel though looks a little weird like dust or something underneath it. Rust is visible on the metal plate and marks on the board.

has it ever been wet? And you've owned this from brand new?

For manuals you could try TC-P54VT25, bigger but should be same construction and engineering .

Are you in SE Q

I've had the TV from new. Only done 3750 hours.... There are little bubble or solder blob like things I noticed in some of the ribbons. Thought that was normal for the TV? No water ever no. Not sure why there is white stuff on the metal. I didnt notice it till I looked that the photo I'd taken. The ribbon you refer to is I assume the ribbon thats encased in glass? I dont see how that could rust though? Second photo is badly focused too. I can take some more photos of the ribbons if that is of interest?

[jjanssen7]

Re: Panasonic 50" VT20 arcing at edge of panel to frame

I think you may have been on to something here:

"For the sake of completeness when I first had the probelm I ended up pulling a lot of the metal buffer cables off and metal frames when I couldnt find what was causing the arcing. When I re-assembled the arcing was gone. I did not know what but it worked fine for a period of time. Now the arcing is back like I expected. (I left the back of the TV off as I knew I hadnt really fixed the problem"

If it were my TV, I'd remove all the boards and check places where they ground to the chassis. Use a soldering gun to put fresh solder on the grounding pads on the boards top side and bottom side. Check and clean the discharge ribbons (x-main/x-sus on other brands... the ribbons opposite the buffer board side). Those are "free" things you can do that ensure everything is grounded properly.

The reason I say that is replacing one board fixed it temporarily... replacing a board can reseat those grounds for a short time.

[tw2005]

Re: Panasonic 50" VT20 arcing at edge of panel to frame

Ah that rust you mention on the board heatsink? The white shit? I bought a 35$ board to test if it was that board. It made no difference. Should have swapped it back before I took that photo. I've had the TV from new. Only done 3750 hours.... There are little bubble or solder blob like things I noticed in some of the ribbons. Thought that was normal for the TV? No water ever no.

3750 hours, broken from lack of use

Read this

https://www.badcaps.net/forum/showthread.php?t=44737

I've got a S20, same era or generation , I've looked at the panel and ribbons on the SS side, just looks weird on yours , could be the lighting. The rust is on the panel chassis edge. The heatsinks on the SS are alloy.

Got no idea of solder blob things. better get some clear images of the solder blobs unless you're talking C boards and the ribbons to the panel top and bottom.

[infrag]

Re: Panasonic 50" VT20 arcing at edge of panel to frame

And no I'm in Western Australia.

Is there any merit and getting another power supply for this TV? Can get on for around $50. AU
I've already tried a replacement Zsus board. Made no difference. It was $35 on ebay so thought it was worth a go as I had nothing else to go on. I dont really want to throw too much money out the window though if the panel itself could be the problem.

[tw2005]

Re: Panasonic 50" VT20 arcing at edge of panel to frame

I don't see it being a P board. And yes WA is out of my reach. It you were handy I'd love to eyeball it myself. I had a 65V10 arcing out from the SS to the panel chassis that was due to polyester caps breaking down. would run until warm then 8 blinks.

Could hear it arc then in a dark room saw it, expected dust build up and then with the SS out the caps were split from heat.

I wonder, any cracked polyesters on this anywhere even on the SC? I think we had someone with burnt cap on the SC once but that was a shutdown with error blinks

[tw2005]

Re: Panasonic 50" VT20 arcing at edge of panel to frame

Here's an image from a v20

[infrag]

Re: Panasonic 50" VT20 arcing at edge of panel to frame

The white stuff on the ribbon is encased in glass. The frame I've looked at and it seems like scrape marks rather than rust/corrosion. I could be wrong though. I've definitely had no water spills or water anywhere near this TV. The only thing weve had is some humidity lately but that shouldnt kill a TV.

I've taken the PS our and tested some of the caps out of circuit... they were all spot on according to the meter. I swapped the SS board out and it performed exactly the same.

The TV has never shut down while its on so its bloody weird.

I feel like the TV has barely been used over its life (I said medium use before I checked the service menu). Would begging/asking Panasonic for help for my dangerous arcing from the front of my TV get me anywhere you reckon?

I love this TV still so I dont really care about getting another model... Just want the stupid arcing to stop...

[tw2005]

Re: Panasonic 50" VT20 arcing at edge of panel to frame

The white stuff on the ribbon is encased in glass. The frame I've looked at and it seems like scrape marks rather than rust/corrosion. I could be wrong though. I've definitely had no water spills or water anywhere near this TV. The only thing weve had is some humidity lately but that shouldnt kill a TV.

I've taken the PS our and tested some of the caps out of circuit... they were all spot on according to the meter. I swapped the SS board out and it performed exactly the same.

The TV has never shut down while its on so its bloody weird.

I feel like the TV has barely been used over its life (I said medium use before I checked the service menu). Would begging/asking Panasonic for help for my dangerous arcing from the front of my TV get me anywhere you reckon?

I love this TV still so I dont really care about getting another model... Just want the stupid arcing to stop...

Highly unlikely. They're not terribly interested especially 7 years down the road. The 2011 models were plagued with bad earths blowing SC boards and loose screws. Did they do a recall or anything? Nope. A few of these V20 blew early on SC boards to. Mine had 2500hrs and another had 3000hrs.

Anyway, maybe comparing yours in a different light but yours looks dirtier, there's unusual spots under the glass, there is a brown stain or spot near that ribbon in front of the panel, the metal work looks etched in places and I can see debris.

I have no answers, it's a real mystery. maybe the panel is breaking down, honestly don't know but if you can get the bezel off safely and insulate it, if that solves it and it keeps running for a while so be it. It is possible what appears to be rust on that edge maybe orange reflection of the ribbon.

[infrag]

Re: Panasonic 50" VT20 arcing at edge of panel to frame

Well thanks very much for your help. I'm guessing that the only real idea then is that its the panel and theres no real fix? I'd hoped this wasnt the case but it is what it is.

Theres someone selling a 65vt20 on gumtree that wont turn on. Are my TV's parts interchangeable at all?
They are asking for too much but maybe I can put in a lowball offer...

[petehall347]

Re: Panasonic 50" VT20 arcing at edge of panel to frame

you could try spraying insulating lacquer onto the metal frame .
or brush on like this stuff .says 60kv ...
http://uk.rs-online.com/web/p/electr...quers/1991480/

[maxvalutech]

Re: Panasonic 50" VT20 arcing at edge of panel to frame

Just a thought - do you live near saltwater?

[budwich]

Re: Panasonic 50" VT20 arcing at edge of panel to frame

hmmm...
just back to the meter testing you mentioned earlier... you tested the grounds thru resistance and NOT voltage right? A voltage test is not really useful.

hopefully, you aren't ready to give in yet... :-)

how about some more testing... it might be a bit more dangerous since you don't know what voltage you are dealing with so some care should be used.

anyways, you can try the following. remove the outside frame (use "bezel" to designate this frame). So according to your previous posts, if I understand which frame is which, there is no longer any arcing from the panel frame to anywhere... right? If true, then now you need to do some measurements ... carefully. Find a known, good, best ground... place one meter probe there. Then take the other meter probe and "touch" / check the remaining panel frame members and determine any voltage readings that you may see. Check both ac and DC ranges (use high first and down from there, or auto range if equipped). This will hopefully give you a better idea of what you are dealing with and might give you clues as to where the voltages are coming from. Go from there.

[flocko]

Re: Panasonic 50" VT20 arcing at edge of panel to frame

My thoughts for what they are worth, I would check your incoming mains supply. Earth to phase (live) and earth to neutral. I am not sure if you have earth leakage protection on your household supplies in Australia, but in the days when I worked with earth loop systems, these have in the past given me some very strange faults with electronics, as this seems to be a grounding problem with the frame of the set well worth a check

[budwich]

Re: Panasonic 50" VT20 arcing at edge of panel to frame

I've had the TV from new. Only done 3750 hours.... There are little bubble or solder blob like things I noticed in some of the ribbons. Thought that was normal for the TV? No water ever no. Not sure why there is white stuff on the metal. I didnt notice it till I looked that the photo I'd taken. The ribbon you refer to is I assume the ribbon thats encased in glass? I dont see how that could rust though? Second photo is badly focused too. I can take some more photos of the ribbons if that is of interest?

have you removed the "solder like blobs" from those places?

[tw2005]

Re: Panasonic 50" VT20 arcing at edge of panel to frame

My thoughts for what they are worth, I would check your incoming mains supply. Earth to phase (live) and earth to neutral. I am not sure if you have earth leakage protection on your household supplies in Australia, but in the days when I worked with earth loop systems, these have in the past given me some very strange faults with electronics, as this seems to be a grounding problem with the frame of the set well worth a check

Majority of homes or modern homes have them. Possibly in the 90's they became mandatory. Unless you test them regularly you can never be 100% sure they are doing their job.

Looked in the video it's arcing from the glass panel

[tw2005]

Re: Panasonic 50" VT20 arcing at edge of panel to frame

Well thanks very much for your help. I'm guessing that the only real idea then is that its the panel and theres no real fix? I'd hoped this wasnt the case but it is what it is.

Theres someone selling a 65vt20 on gumtree that wont turn on. Are my TV's parts interchangeable at all?
They are asking for too much but maybe I can put in a lowball offer...

No, and you'll need more info like how many blinks of the RED standby LED. Most likely failure will be shorted SC board

There are several versions, you'll need the right one but realistically the only way assuming it's the SC is to rebuild it.

Not a beginners job

[maxvalutech]

Re: Panasonic 50" VT20 arcing at edge of panel to frame

I got a Samsung plasma about 4 years old and found problem was Y board so took it out - on rear where insulating pad is all around was moisture - normally a bit of this and non conductive but this seemed more than should be - cleaned it up put board back and all goes well. I recall owner told me they lived on a clifftop road directly above the sea and had recently moved. North east breezes in our town feature in summertime and bring along salt laden moisture which is deposited on whatever is around even inside. We too had unusual high humidity when the TV went down. To my mind the salting attracted the moisture and so interfered with board circuitry. In the old days of CRT when sets in holiday homes hadn't been used for awhile the people would arrive and switch on TV to be met with snap crackle pop from arcing caused by salting and moisture content - cleaning up the tube and throat connections usually fixed things. For our own TV it was covered with a blanket when not in use as our house was right on the beach.

[infrag]

Re: Panasonic 50" VT20 arcing at edge of panel to frame

Well I have to say I dont live anywhere near the sea or salt that I know of. The TV was not that dusty either.

I understand the idea of insulating the metal bezel of the TV. However before I try that idea out I have a couple of questions.

Why is this metal in the first place? Secondly the metal has a pad on it that rest against the glass. I guess this is to make sure the metal doesnt directly touch/scratch the glass. This pad is conductive. I've used a meter to check and its a fairly low resistance from it to the frame. Why is this conductive if its not meant to discharge the panel in some way? Also wouldnt the electricity thats arcing just flow through this pad? Why the arcing in the first place if this is in contact with the glass/screen nearby where its arcing?

Second question is if I insulate the metal and/or remove that pad where would the charge that builds up go? Would it cause damage to anything else possibly or arc to me if I put my finger near the glass (or rather my kids to be exact) ?

I might try out the idea mentioned about trying to measure the voltage of the spark. Even if it doesnt help anything the idea seems interesting

Does anyone know the voltages I'm meant to measure the test points on the power supply /other boards to see if its perhaps over voltage or something like that?