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General => General Technical Chat => Topic started by: kuddo on March 13, 2013, 10:01:05 pm

Title: Ferrite Cores on the PSU cables ? Any good?
Post by: kuddo on March 13, 2013, 10:01:05 pm
I have lots of ferrite cores. Will it do any good to put ferrite cores on each group of cables (PC power supply) ? I've read somwhere that those high frequency parasitic currents are sent back to the PSU if i do that and it's not good for it because the PSU aren't meant to withstand this effect.
Title: Re: Ferrite Cores on the PSU cables ? Any good?
Post by: smashedProton on March 14, 2013, 05:31:10 am
More series inductance won't do inthing assuming your psu is well designed.  But see for yourself with a scope.  That is the scientific method after all.
Title: Re: Ferrite Cores on the PSU cables ? Any good?
Post by: Neilm on March 14, 2013, 06:52:18 am
Ferrites are quite often used to suppress high frequency emissions from equipment. Generally, they provide impedance at frequencies in the order of 50MHz - 300MHz. I wouldn't bother putting them on to a PCs PSU. The high frequencies will mostly stay on the motherboard - that is the purpose of all those capacitors.

Neil
Title: Re: Ferrite Cores on the PSU cables ? Any good?
Post by: AndyC_772 on March 14, 2013, 07:40:27 am
The only purpose of putting a ferrite on a power cable is to reduce the radiated emissions from that cable. There's no effect on the PSU itself.

If you have a problem with interference on a nearby radio or TV then adding them might help - although I'd be surprised if it actually makes any difference in practice. If you don't have a radio interference problem, they're a waste of time and completely unnecessary.