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Volenti · 04-13-2002, 06:44 AM

Ahh, yea forgot you lived in land of the long white cloud

I was having a closer look at one of my dead powersupplies and the main caps have a 200WV rating on them. Now normally caps are rated just in volts (and their capacity), not watt/volts (if that is what WV means) taken at face value that's over 100v short of what they should be (rectified 240v being around 340v) so unless their's a voltage divider or something before them theorectly they should go boom...*frowns, has an even closer look at the board traces...*

Ahha!, their not in paralell like I thought, their in series, that makes more sense.

There are some other components that could cause trouble should they fail , mainly medium and high current diodes that would do nasty things should they decide to pass current in both directions. It can be difficult at times to find the exact fault since a critical component can set off a chain reaction when it fails, taking out other components down the line, collateral damage so to speak.

I'd put my money on either the caps being under spec voltage wise, 200+200=400 with the 340v DC they see, not a huge saftey margin, or another component failing, and causing the caps to see 340 each, not between them, then boom.

Note, electronics is only a hobby of mine, I could, and have been wrong before.

04-13-2002, 06:44 AM	#30
Volenti Cooling Savant Join Date: Jan 2002 Location: in a nice cool spot Posts: 427	Ahh, yea forgot you lived in land of the long white cloud I was having a closer look at one of my dead powersupplies and the main caps have a 200WV rating on them. Now normally caps are rated just in volts (and their capacity), not watt/volts (if that is what WV means) taken at face value that's over 100v short of what they should be (rectified 240v being around 340v) so unless their's a voltage divider or something before them theorectly they should go boom...frowns, has an even closer look at the board traces... Ahha!, their not in paralell like I thought, their in series, that makes more sense. There are some other components that could cause trouble should they fail , mainly medium and high current diodes that would do nasty things should they decide to pass current in both directions. It can be difficult at times to find the exact fault since a critical component can set off a chain reaction when it fails, taking out other components down the line, collateral damage so to speak. I'd put my money on either the caps being under spec voltage wise, 200+200=400 with the 340v DC they see, not a huge saftey margin, or another component failing, and causing the caps to see 340 each, not between them, then boom. Note, electronics is only a hobby of mine, I could, and have been wrong before.