LG Flatron L204WS

[matthmal]

Hi,

I have another monitor, an LG Flatron L204WS which was blown by means of a surge.

Every time that I plug it into the mains, my house electricity cuts off.

What I have Done:

I looked for possible bad caps but physically they all look ok.

I noticed two capacitors which have some green marks on them. You will find these in the attachments.

I don't know which is the fuse in order to test it.

Hope that someone can help me.

[Pentium4]

Re: LG Flatron L204WS

The fuse is that black thing to the left of that X cap (going off of the 4th picture) you should test it

[matthmal]

Re: LG Flatron L204WS

which one please? How would you know which is the fuse?

[budm]

Re: LG Flatron L204WS

F101 (it has black shrink tubing on its body) next to the white 2-pin connector and the yellow capacitor.
If the fuse is blown, then you plug this unit into the outlet, it should not cause the main electric to cut off isnce it will not draw any current due to blown fuse.

[selldoor]

Re: LG Flatron L204WS

Hey - you never said you had this - sockets look same as the 1504s?

Pictures are just a little out of focus and we need to see the backs of the boards.

If you can see check when the board is in the frame that the mains and fuse solder joints do not touch the frame?

[matthmal]

Re: LG Flatron L204WS

I have just brought this yesterday that's why and I also have a tv.

I will take the pictures and post them here. The fuse is fine hehe. How can I test this as I can't connect it to the mains.

[selldoor]

Re: LG Flatron L204WS

Check the board doesnt touch the frame as above, is one test.

Meter on 2000 ohms put one probe on each mains input pin and report.

Do it again with just the power board and nothing else connected.

[matthmal]

Re: LG Flatron L204WS

Power on right?

[selldoor]

Re: LG Flatron L204WS

WRONG NO NO NO.!
Basic rule
Test voltage power on Test resistance power off

Besides which you have already said it just blows

[selldoor]

Re: LG Flatron L204WS

Just had a thought - perhaps its the mains lead that is faulty?

Test that - unplugged- meter on ohms 2000 see if the live and neutral short out.
result should be the same as just holding the probes apart. - If there is an earth wire try it again live > earth neutral>earth

[budm]

Re: LG Flatron L204WS

I cannot see how the fuse on the board is OK, it is only about 2~3A fuse but it can take out the house breaker that is rated at 10~20A. Something must be shorted out BFORE the fuse.

[retiredcaps]

Re: LG Flatron L204WS

Power on right?

Never for resistance measurements. Otherwise

[matthmal]

Re: LG Flatron L204WS

Thanks all for your replies. With reference to the following quoted test:

Just had a thought - perhaps its the mains lead that is faulty?

Test that - unplugged- meter on ohms 2000 see if the live and neutral short out.
result should be the same as just holding the probes apart. - If there is an earth wire try it again live > earth neutral>earth

The results well all the same as holding the probes apart.

With reference to the below quote:

I cannot see how the fuse on the board is OK, it is only about 2~3A fuse but it can take out the house breaker that is rated at 10~20A. Something must be shorted out BFORE the fuse.

I did test the fuse with a meter and it beeped so it means that it is ok. I can't understand as this monitor was blown with a surge during a thunderstorm.

[retiredcaps]

Re: LG Flatron L204WS

I did test the fuse with a meter and it beeped so it means that it is ok.

A beep is no guarantee that the fuse is good. Some multimeters will beep for resistance readings less than 1800 ohms.

A good fuse will measure less than 1.0 ohms.

[matthmal]

Re: LG Flatron L204WS

ok so the reading is 000. more photos will follow

[matthmal]

Re: LG Flatron L204WS

please find attached photos of the back of the board. There are photos from different angles just to make it clearer and easier to see.

[selldoor]

Re: LG Flatron L204WS

Picture one is ok the other three are not.
Can you still do this from an earlier post POWER OFF

Check the board doesnt touch the frame as above, is one test.

Meter on 2000 ohms put one probe on each mains input pin and report.

Do it again with just the power board and nothing else connected.

[matthmal]

Re: LG Flatron L204WS

I already did it as written in a previous post and the results where the same as it if the probes are not touching. I did this test with the board out of the frame.

[selldoor]

Re: LG Flatron L204WS

Power off meter on ohms 2000 Can you also check across TH101 and VR 101
both near the mains socket. Is that green component behind the TH101 glass and does it look broken?

[selldoor]

Re: LG Flatron L204WS

I already did it as written in a previous post and the results where the same as it if the probes are not touching. I did this test with the board out of the frame.

I thought that answer just related to the mains lead test as that is what you quoted