normande 32 -vestel

[willyam1]

hi.
tv come with problem thet its work ok and after 50-60 min shut down to stby.
it was like the customer said.
i open it and start to check trying to operert it but its giving flick to the backlight and then stby.
p.s17PW26-4 V.1.
ALL CAPI OK NO BULLGING .POLY CAPI 22N OK .
3.3V STB 5VSTB.
3.3V OK 5V OK.
INSTED 24V 23.2V INSTED12V 11.4V.
BIG CAPI 322-330V its seemsb that the pfc section works but low should be 370-400v .
i check everthing diode opto pfc ic fan75259 no shorts vcc 15v steady no rippel to that ic.
not shure if problem is in p.s but usely its the pfc problem.bl on ok anyone hade this problem in this power supply.
willyam

[tom66]

Re: normande 32 -vestel

This PSU has a flyback output type PFC, so you don't expect 390V across the 22u/450V cap.
1st try warming up PSU and see if it will shut down - use hairdryer etc.

[willyam1]

Re: normande 32 -vestel

thanks tome i already try it no joy.its150uf/450v
willyam

[willyam1]

Re: normande 32 -vestel

dear tom.
i found in electro tanya web thet one of the tech said to replace the 22n to 15n i did it and now tv works 24.5v 12.3v.
i will put it to works and see the finel result.330v in big capi i dont understand what is the reason to it is 3 nf diffrent could help it i dont understand it from the diagram can you explain the reason?
willyam