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Old 03-31-2008
cypherpunks cypherpunks is offline
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Originally Posted by Stefan555 View Post
The OCP's are always programmed to shut the psu off at a higher current than specified on the label, no matter what is printed on the label.
Well, actually, the point is that there's some tolerance on the OCP threshold level. The value on the label is a "guaranteed not to shut down" number, while the 20 A limit in the ATX spec is supposed to be the "guaranteed to shut down" number. So they typically design them to 19 A, plus or minus 5%.

All this because measuring more exactly than 5% costs more money.

It'll shut down somewhere between 18 and 20 A, and not even the manufacturer knows where.
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