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Purpose of cap on ac line of PC power supply

Started by Bob Engelhardt May 4, 2019
I am re-purposing a PC power supply and there is a "0.47k" cap across 
the incoming AC line.  What's that for?
On 2019-05-04 17:02, Bob Engelhardt wrote:
> I am re-purposing a PC power supply and there is a "0.47k" cap across > the incoming AC line. What's that for?
Interference suppression. Google 'X-capacitor'. Before you ask, there is also a 'Y-capacitor'. They're a bit special because they have to conform to pretty strict safety standards. Jeroen Belleman
On 5/4/2019 11:18 AM, Jeroen Belleman wrote:
> On 2019-05-04 17:02, Bob Engelhardt wrote: >> I am re-purposing a PC power supply and there is a "0.47k" cap across >> the incoming AC line.  What's that for? > > Interference suppression. Google 'X-capacitor'. > Before you ask, there is also a 'Y-capacitor'. > They're a bit special because they have to conform > to pretty strict safety standards. > > Jeroen Belleman
Thank you.
On Sat, 04 May 2019 17:18:42 +0200, Jeroen Belleman wrote:

> On 2019-05-04 17:02, Bob Engelhardt wrote: >> I am re-purposing a PC power supply and there is a "0.47k" cap across >> the incoming AC line. What's that for? > > Interference suppression. Google 'X-capacitor'. Before you ask, there is > also a 'Y-capacitor'. They're a bit special because they have to conform > to pretty strict safety standards.
*Part of* interference suppression. Their should be some proper filtering in there besides. -- This message may be freely reproduced without limit or charge only via the Usenet protocol. Reproduction in whole or part through other protocols, whether for profit or not, is conditional upon a charge of GBP10.00 per reproduction. Publication in this manner via non-Usenet protocols constitutes acceptance of this condition.
On 2019-05-05 18:29, Cursitor Doom wrote:
> On Sat, 04 May 2019 17:18:42 +0200, Jeroen Belleman wrote: > >> On 2019-05-04 17:02, Bob Engelhardt wrote: >>> I am re-purposing a PC power supply and there is a "0.47k" cap across >>> the incoming AC line. What's that for? >> >> Interference suppression. Google 'X-capacitor'. Before you ask, there is >> also a 'Y-capacitor'. They're a bit special because they have to conform >> to pretty strict safety standards. > > *Part of* interference suppression. Their should be some proper filtering > in there besides. >
If you have something truly useful to contribute, do so. Otherwise you don't matter. Jeroen Belleman
On Sun, 05 May 2019 22:37:25 +0200, Jeroen Belleman wrote:

> If you have something truly useful to contribute, do so. > Otherwise you don't matter.
If you have something truly useful to contribute, do so. Otherwise you don't matter.