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Old 09-10-2016, 10:27 PM   #1
Join Date: Aug 2013
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Default Disaster of 400 V Caps

My Airties Air5440 Adsl Modem was working properly at 7/24 for three years .
it is a quality device.

Recently i often see
"The service is unavailable." message at browser pages.
at least 3 times a day. it needs restart the modem.

and also modem is very hot. i suspect the adapter that is labelled DVE 9V.
i replace it. " The service is unavailable." message disappered at site.

I opened to the adapter and see red area at pcb. it frys.

Caps looks like O.K.they must be 4,7 uF (400 v)
But Multimeter says it's not.

and i also controlls other corrupted bulb lamps, swich and modem adapters
i measured and see 5200 uF ,4800 uF, 2200uF
all of them exceed to thousands. i change these.
everthing's O.K. now.

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Last edited by Per Hansson; 09-12-2016 at 12:37 PM.. Reason: uploaded offsite images
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Old 09-11-2016, 03:26 AM   #2
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Default Re: Disaster of 400 V Caps

what brand of caps was installed in the power supply?
Don't buy those $10 PSU "specials". They fail, and they have taken whole computers with them.

For computer parts, go to Newegg

For electrical stuff(pushbuttons, capacitors, etc), use Digikey

My computer doubles as a space heater.

Windows 10? Only if you like forced, buggy updates and 24/7 telemetry.

Samsung = Seagate = Seatrash = Trashgate
Don't buy Seagate drives. Don't use Seagate drives. If you have any in service right now, make plans to replace them ASAP.

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Old 09-11-2016, 09:37 PM   #3
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Default Re: Disaster of 400 V Caps

It's always plugged in the mains, so it's ALWAYS ON
When loaded, heat is produced which has nowhere to go, because the adapters are usually sealed for safety
So heat keeps the capacitors always warm which shortens their life span.
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Old 11-05-2016, 07:32 PM   #4
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Default Re: Disaster of 400 V Caps

and those cheap caps are in trouble even when not overheated 24/7.
i see this type of failure often.
i replace all with high quality parts and it outlasts the units usefulness.
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Old 11-15-2016, 12:53 AM   #5
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Default Re: Disaster of 400 V Caps

either i get a better design power adapter or recap with better specs on it.
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