Element 32le30q

[slickrickybobby89]

this set has a power supply issue, when the set os turned on everything starts fine. Screen comes on and looks great, then it faults and goes back to standby. I opened up the set and visually inspected the power supply and found a burned up ceramic capacitor it was a 6000v 15p, i swapped it with another i salvaged from another board, fired it up with fingers crossed, and i got the same problem. From there i proceded to disconnect the main board, and jump the pson pin and bkon pins to standbye, when plugged in the power supply powered on, then shut back off, i tried again this time disconnecting the backlights completely, and it still shuts down once powered. I removed the 5v from the bkon pin, and the power supply stayed on, and never faulted, allowing me to test all pins, and all of the voltages are correct. With no power at the backlights as i would assume should happen, since the backlights are not being told to turn on. Also telling me that the backlight circuit is the reason the power supply is faulting. Im still learning my way around a power supply but i am not afraid of testing, can anyone offer some guidance as to where i should look next? I've removed what i believe to be the inverter for testing, but cant find a pinout sheet online, but i do know there is a short between the two marked pins in the photo. Thanks for any offered help, ill be with the set all night if anyone has some free time.

[budm]

Re: Element 32le30q

DCR of the transformer will show very low resistance.
So the blue ballast cap you replaced have the same capacitance and Voltage rating?
If you do not have ALL the working lamps connected, it will trip protection circuit, it will only take one bad lamp to trip the protection circuit.
Did you also check the resistance of all four blue ballast caps to see if any one of them show leakage resistance?

https://www.badcaps.net/forum/attach...0&d=1471213443
You can which which two pins are for the primary.
Since there is only one inverter transformer, it is hard to know if the secondary side wind is good or not. What resistance do you get on the secondary winding?

[slickrickybobby89]

Re: Element 32le30q

The only method of testing i have is a DMM, i checked the resistance between the ballast caps and for the top 2 which are 10p 6000v i had around .030nf, i asume that is picofarads, and the other 2, which are 6000v 15p test at .022 nf, as for the inverter, there is no resistance across any pins whatsoever, i measured in ohms, is that correct?

[slickrickybobby89]

Re: Element 32le30q

I get a resistance of 1.5 ohms between the two pins that show shorted, im still not sure how to identify which pins are which on this inverter.

[budm]

Re: Element 32le30q

https://www.badcaps.net/forum/attach...6&d=1471213443
The transformer only has one primary winding, those two pins are the primary winding and it will show very low Ohms reading (DCR: DC Resistance), it also has only one winding for the Secondary high Voltage side.
You can see how the wires are attached to the pins.
The primary winding of the inverter transformer is being driven by that yellow transformer next to it, if you trace out the connections you can see how they are connected.

[slickrickybobby89]

Re: Element 32le30q

So should i pull and test the inverter next to it? Based on what you said we can assume the inverter transformer to be good correct? I removed the ballast capacitors in question and placed them into a functioning power supply, and they operated the other power supply, i did this thinking that maybe my dmm is just to low quality to test such a low capacitance, but they appear to be fine. I have also tested mosfets, but they tested fine. Thanks for the help bud.

[slickrickybobby89]

Re: Element 32le30q

I retested the supply, and this time tested the output of the backlights, with them hooked up, i get 18v dc until the backlights actually kick on, when yhe backlights kick on the voltage spikes to 33v, and immediately begins dropping back to 0v, whit the lamps disconected, i get 33v on both outputs, untill it shuts off. Im pulling the tranformer to test now.

[budm]

Re: Element 32le30q

I retested the supply, and this time tested the output of the backlights, with them hooked up, i get 18v dc until the backlights actually kick on, when yhe backlights kick on the voltage spikes to 33v, and immediately begins dropping back to 0v, whit the lamps disconected, i get 33v on both outputs, untill it shuts off. Im pulling the tranformer to test now.

Are you testing the DCV on the HV connectors CON5, CON6?
Do not do that, when the circuit is working you will have about 2000VAC on the HV connectors, and you can easily blow out the meter.
Can we see the pictures of the whole backside of the TV showing all the boards and how they are connected together?
There are so many versions of this model.
http://www.shopjimmy.com/catalogsear...lement+32le30q

Which version of the power supply do you have?

OK, it looks like you have version 3.1 Power supply based on you pictures.

[slickrickybobby89]

Re: Element 32le30q

I have version 3.1, im also posting a closeup of the area where the original damage occured, notice the discolored connector, and the 2 newer blue ceramic capacitors. I did verify that the replacement was the exact same part before replacing, both were stamped 15j 6kv, if im correct that means 6000v 15 picofarads.

[budm]

Re: Element 32le30q

I have version 3.1, im also posting a closeup of the area where the original damage occured, notice the discolored connector, and the 2 newer blue ceramic capacitors. I did verify that the replacement was the exact same part before replacing, both were stamped 15j 6kv, if im correct that means 6000v 15 picofarads.

That is correct, 15pF 6000V.

[slickrickybobby89]

Re: Element 32le30q

How do i identify this transformer, if that's what it is, i tried looking this part # up online and, i can't find anything relevant.

[slickrickybobby89]

Re: Element 32le30q

Thank you bud, i know this isn't a set that is really all that valuable, but i am trying to teach myself the basics of electronics, and this is helping me to understand/identify what each component is doing or supposed to be doing. Your knowledge has helped me a great lot the last few weeks. I have no teacher lol.

[vinceroger69]

Re: Element 32le30q

Budm Could a failing/failed ccfl tube cause this?

[budm]

Re: Element 32le30q

Can I get a straight shot pictures of the bottom side of the board?
This one is cutout and dark on the edge.
https://www.badcaps.net/forum/attach...3&d=1471213443

[slickrickybobby89]

Re: Element 32le30q

Bottom side pics

[budm]

Re: Element 32le30q

Hmm, the pictures were taken before the Inverter transformer (T302) is removed?
I also see that you unsolder the Standby power transformer pins.

[budm]

Re: Element 32le30q

This is what I have so far.
Picture provided by shopjimmy.

[slickrickybobby89]

Re: Element 32le30q

Is there any way to tell if it might be the backlights and not actually the board? I hadn't considered the bulbs being bad, i assumed power board because of the blown capacitor.

[budm]

Re: Element 32le30q

Not easy to test the LAMP in the LCD panel since you cannot see what the ends of the lamps look like, they turn black when lamps are worn out or light up with pink glow.
See post 11 for example.
https://www.badcaps.net/forum/showth...631#post680631

[slickrickybobby89]

Re: Element 32le30q

Ok, i will build this with and old bulb i have, the one question i have about it though, is on my setup, i have single wires for the lcds power, both are similar, when i attempt to power the circuit, should i use one wire to each side? Or do i need to build 2 test bulbs and hook them up independenly?