Samsung Plasma PN51D550C1FXZC

[tom66]

Re: Samsung Plasma PN51D550C1FXZC

Ok I found something very strange. When I remove the power from the circuit, the VE on the y main stays at around 90V and isn't discharging. Any ideas? Also, what can I check on the scope to troubleshoot .

Well, with no load on the Ve circuit, how will it discharge?

You can try checking the output of the X-main, this is the side connected to the orange plasma panel ribbons.

Also note Satiniser's comments as sometimes shorts can be hidden behind other devices - you should check all IGBTs for shorts.

[satinser]

Re: Samsung Plasma PN51D550C1FXZC

Yes in particular RJP30H1 as I pointed out on the both occasions when we had this model in for repair they had also gone short. Their a bit of a pain to replace though, you have to remove 2 of the large 150uf 250v green caps to gain access to the screws to the heatsink. Incidentally as pointed out its very difficult if not impossible to get hold of these boards. So for quick turnaround best to repair them. Never had a problem with them failing again though.Touch wood!

[tech2014]

Re: Samsung Plasma PN51D550C1FXZC

thanks guys. Obviously I missed a part on the xsus board. I will look at RJP30H1 and the other IGBTs.

[tech2014]

Re: Samsung Plasma PN51D550C1FXZC

satinser, thank you very much. I checked the RJP30H1 and both were shorted.