P-Vision 42" LCD PSU tripping 17PW16-2

[angelos]

HI Guys,
I have recapped the entire PSU because there were bloated caps and that did not solve the problem since the power supply is still tripping. The standby 3.3V and standby 5V are both fluctuating up and down.
I even unplugged the board and started it up with the same tripping but no luck, still the same. I have thought of purchasing a refurbished PSU but thought while i wait for it perhaps someone who know these PSU's can give me some pointers.


PS: I have read previous posts but it did not help solve the problem.

Many thanks
Angelos

[arizanotlari]

Re: P-Vision 42" LCD PSU tripping 17PW16-2

https://yadi.sk/i/9vcwwNCBSFjiaA

Flowchart. H meaning No. E meaning Yes.

[angelos]

Re: P-Vision 42" LCD PSU tripping 17PW16-2

Thanks, i will try to follow the turkish fault tree but it wont be easy. Like i said my standby 5 and 3.3V is tripping continously.

[arizanotlari]

Re: P-Vision 42" LCD PSU tripping 17PW16-2

when unplug psu from mainboard, connect 5V to stby pin of psu. if all voltages are ok check mainboard for shortcircuit.

google translate flowchart :

When the pfc circuit is active, it should be 380 volts in c819. If there is any problem in the pfc circuit, it will be 310 volts in c819.

The d824 feeds the pfc circuit. The ic802 supply voltage should be 12 volts in normal condition.

r829 is the current sensitivity resistance of the pfc circuit. If r829 resistance fails, the pfc circuit goes into protection.

ic828, lm317 linear regulator. ic828 is the vcc supply source of pfc and half bridge control. Check the vcc problem ic828.

The vcc pin of the standby controller ic806 is fed from pin 1 of the tr803. operating voltage is between 12-19 volts.

If the ic806 supply goes below 12 volts or above 19 volts, it enters protection mode.

The icc7 half bridge controller's vcc voltage should normally be 12 volts.

The tr805 input pin should be measured in normal condition at the dc resistor oscilloscope and 400 kHz 400Vpp square wave.

If there is a problem in the 3.3 volt line, ic825 should be checked.

The ic824 on / off switch must be between 3.3 volts standby and 3.3 volts power on. If there is a problem in the 3.3-volt circuit, check ic824.

If there is a problem in the 5-volt line, check the Q832.

If there is a problem in the 12-volt line, check the Q827.

If there is a problem in the 24 volt line, the card enters protection. When switched to protection, the collector of Q802 will be 0 volts.

If there is a problem in the 24 volt line, check the Q815 Q816.

If there is a problem with the 5 volt standby line, check ic829.

If there is a problem in the 33-volt line, the d821 should be checked.

after a period of time the device goes to the booth: ic802 (fan7529) from the block to the controller voltage to come to the controller (450 volts) the device goes to protection

installation and protection, running after warm-up or self-closing: c877 c878

switch to stand or sometimes no standby: change r838 to 2.2 kiloohm

fuse waste: tr806 tr802 tr801 q803 d824 d800 check l817

stby3.3 volts: check ic825 tr803 l804, respectively. If the relevant materials are intact, check for 19 volts on the c801. If there is no voltage, replace the d807. If there is a voltage, check / replace the ic806 d823 ic801 Q831 Q833 Q834 d847 d854

vcc12 volt no: Q824 l811

vcc5 volt no: Q832 d845 d846

vcc3.3 volt no: ic824