EEVblog Electronics Community Forum
Electronics => Repair => Topic started by: negativ3 on September 21, 2017, 01:01:37 am
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Hi all,
Had a strange occurrance with a monitor. Left the PC rendering overnight and made sure all monitors were in standby.
The Dell standby was off (power button light out), indicating no power, so I removed the power cable and re-inserted it, with the same result.
When inserting the cable, I heard the "crackle" of electricity as the contacts mated.
I unplugged the monitor again, and left it for 10 minutes, after which I plugged it back in and it works.
Is this some kind of protection or am I seeing the start of a failure in the PSU? The PSU is internal to the monitor.
Put it back into service and wait until it fails, Dave? :)
Thank you.
Andy
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There are many monitors. May we have a model number? How old is the unit?
T
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My apologies, it's an Ultrasharp 1905FP, at least a decade old.
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Thanks!
Common issue as you correctly assumed, the PSU. Specifically the capacitors from that era were particularly bad. I'm amazed it lasted this long...
Recap is fairly easy and inexpensive.
Parts:
Dell 1905FP
[ Max cap height 22mm ]
3 - 1000@10v - 10x16 - Capxon KF - Pana FM == P12353-ND - EEU-FM1A102
1 - 1000@25v - 12x16 - Capxon KF - Pana FM == P12379-ND - EEU-FM1E102
1 - 2.2@50v - 5x11 - Capxon KM - Pana FC == P10313-ND - EEU-FC1H2R2
1 - 4.7@50v - 5x11 - Su'scon - Pana FC == P10315-ND - EEU-FC1H4R7
1 - 10@50v - 5x11 - Capxon KM - UCC KZE 5x7 == 565-1702-ND - EKZE500ELL100ME07D
1 - 22@50v - 5x11 - Capxon KM - Pana FM == P12927-ND - EEU-FM1H220
2 - 220@50v - 10x16 - Capxon KM - Pana FM == P12397-ND - EEU-FM1H221
4 - 470@35v - 13x20 - Capxon KF - Pana FM @ 50v == P12400-ND - EEU-FM1H471
{Sub for FM - UCC KZE == 565-1712-ND - EKZE500ELL471MK20S}
1 - 150@450v - 18x45 - UCC PAG - Not Replaced; not a common failure
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15 caps - 14 replaced
** Note: The FM series from Panasonic has been somewhat deprecated starting 2 years ago. Replacements are in the FR series.
Also, while you're in there, redo the solder on pins of the 2 transformers for the backlights. Known to be a source of problems from poor or cracked connections.
T
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All I can say Toasty is thanks very much, I will get the parts on the way and look at the backlight transformers for sure.
Will update again when all done.
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That crackle could have been arcing due to cracked solder joints on the IEC connector check those too when you open it up.
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Very good point, I will give it a full health check when the bits arrive.