Phillips 37PF5521D dead after power cut

[selldoor]

Re: Phillips 37PF5521D dead after power cut

Dont bother with pic for now perhaps find the second Bridge and see what
voltage is on that - according to the diagram one of them should be fed from the mains before the relay- I have been called to lunch!

[selldoor]

Re: Phillips 37PF5521D dead after power cut

That was quick - the other bridge is on the heatsink on the left hand side of the board (in your pic) Another thing to check is from the red cable connector going left there is a brown?pink? resistor - i think it it fusible so test it as a fuse.

[flocko]

Re: Phillips 37PF5521D dead after power cut

if i have no supply from the power board to the standby board the standby board cannot switch the main power on,just looking on the back of the power supply board were the two pin output to the standby board is ,one side of socket is linked to the glass fuse and then to what look like a small bridge with the other pin also going to the same bridge it also has the 10uf 450v cap across on the other side of the bridge one leg links to pin 3 of the main bridge on the heatsink,and the last pin of the small bridge links to the big transformer on the bottom left of the board, just to help if look to the back of the relay you will see the small bridge that i talk of

[tom66]

Re: Phillips 37PF5521D dead after power cut

OK, see image. Be very careful when testing here. But you should see 325V DC.

[flocko]

Re: Phillips 37PF5521D dead after power cut

no not a thing, i a m starting to look more from the bottom of the broard as the mains comes up to and though the right hand up to that bridge

[selldoor]

Re: Phillips 37PF5521D dead after power cut

Driving me nuts this - see picture.


Tomorrows meant to be a bright day weatherwise perhaps you can
get better pictures and the backs of the boards.

[flocko]

Re: Phillips 37PF5521D dead after power cut

ok had a good look at the power board, from the mains connector side of the unfused side a track runs through resistors 3302 and 3303 were it gets strapped to the chassis it then goes though cap 2307 though the large inverter and on to one side of the small bridge,from the fused side of the mains plug it goes though the fuse though 1005 surge protector then resistor 3304 then on to pin 3 of the big bridge ending at the other side of the small bridge , all of which make me think that the small cap 2307 or resistor 3304 are open circuit, if you recall i was getting higher voltage when i was reading voltage to the chassis that was because i was bypassing these components, now need to pull them and check them out

[selldoor]

Re: Phillips 37PF5521D dead after power cut

ok botheration - didnt realise we have 3 bridge rectifiers - what is the board number of the small one. It could also be faulty where does the circuit go from the other ~ac pin.

[flocko]

Re: Phillips 37PF5521D dead after power cut

no just the two, the small bridge is 6306 ac leg to pin 3 of the large bridge back through 1.8k 3304 next through 1005 s/p onto main fuse, other ac leg of small bridge back through inverter 100nf 50v cap 2307 strap to chassis 1ohm 3303 1ohm 3302 to mains in, this thing has made my head bang ihave put it away now will pull it apart tomorow,will let you know how it goes thanks to you all for the help

[flocko]

Re: Phillips 37PF5521D dead after power cut

Hi again back on the power board again, well the components i listed last night are wrong i looked them up on the parts list from the s/m that was posted , on checking 3304 is 220ohm and checks ok 3302and 3303 4.7m and are also ok 2307 and 2318 the cap i could do with some help on they are marked from top bottom VYI 221K Y! 500- YI760 and are the same? can anybody help me out here thanks

[selldoor]

Re: Phillips 37PF5521D dead after power cut

Are these the yellowish/orange ceramic caps- they dont oftenfail unless
you can see cracks. - Close up pic might help.

221K might be 220uf ie 22 x 10 to the oneth 222k would be 2200uf
22 x 10 squared. and K could be a tolerance 5% or 10%.
500 might be voltage.

Have you tested that small bridge rectifier did you try it on the ac side?

With the power off is there continuity from the ac~ pins to the ac mains connector.

[selldoor]

Re: Phillips 37PF5521D dead after power cut

Hmm may have got my 000's mixed up

221K might be 220uf ie 22 x 10 to the oneth 222k would be 2200uf 22 x 10 squared. and K could be a tolerance 5% or 10%.
500 might be voltage.



Should read

221K might be 220pf ie 22 x 10 to the oneth 222k would be 2200pf
22 x 10 squared. and K could be a tolerance 10%.
500 - 760 might be voltage.

So it might be 0.00022uf which is also .22nf

[flocko]

Re: Phillips 37PF5521D dead after power cut

photo of back of board

[flocko]

Re: Phillips 37PF5521D dead after power cut

photo of unkown components 2307+ 2318 on the back of boad photo you you can now trace up to the small bridge across to pin 3 of large bridge though 3304 back to fuse

[selldoor]

Re: Phillips 37PF5521D dead after power cut

^^^That is a terrible photo - is it a scene from ghostbusters ^^^

Please answer my previous questions?

On the bottom of the board at the bottom of your pic in the middle it looks like the trace is completely missing near 2318 ?

[flocko]

Re: Phillips 37PF5521D dead after power cut

my what good eyes you have i have been looking at this board for over two day how did i miss that will make repair and try it,i will be going to see the optician in the morning to get measured for a white stick if you like you can come down and beat me round the head with it. Thanks

[flocko]

Re: Phillips 37PF5521D dead after power cut

Ok repair done to pw board 340v dc to standby board, green standby light on, now need to check output to relay from standby board

[tom66]

Re: Phillips 37PF5521D dead after power cut

It would be amazing if it's just a broken track. I wonder how that could occur on its own -- maybe factory defect?

[budm]

Re: Phillips 37PF5521D dead after power cut

Darn selldoor, you did it again with your good set of eyes you have.

[flocko]

Re: Phillips 37PF5521D dead after power cut

well i think someone has had a go at this before me, i was told it had not turned on after a power cut and it came to me though someone how knows i like to play with thing,so after having resolved the power supply board problem and restored the supply to the standby board i now have the green light coming on as soon as mains are turned on but no feed to the relay if the power button is hit ,am i wright in thinking that the green light coming on means the standby board 5v must be ok and that the problem is elsewhere.