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-   -   Hold-up time explained (http://www.jonnyguru.com/forums/showthread.php?t=13273)

-The_Mask- 05-05-2016 07:07 AM

Quote:

Originally Posted by sith'ari (Post 124729)
Oh come on.....!!!
I can't resist with what you are writing!!! Again, probably doesn't specify certainty, and i'm not a person that likes risks and ....blah blah blah you know the rest :lol:!!!

There is only one thing certain in life and that is that you die. ;)

Quote:

Originally Posted by quest for silence (Post 124730)
1.2V are not enough? So which is the (general) UVP usefulness/goal?

That should be more then low enough for a 3,3V, 5V and 12V UVP trigger point. You can normally find the UVP trigger point in the datasheet of the secondary protection IC. If it doesn't work it probably means it isn't implemented the right way.
Quote:

Pares cum paribus facillime congregantur. :D
Geen idee wat dat betekent. ;)

rafal_iB_PL 05-05-2016 07:43 AM

Quote:

But if that is the case a UPS is maybe something that you should buy.
It should be pointed out that UPS operation is related to hold-up time, at least for cheaper ones. Cheaper UPS units have non-negligible transfer time when switching to batteries, so hold-up time needs to be longer than that transfer time. If you have online UPS, it doesn't matter, as those run from batteries all the time.

-The_Mask- 05-05-2016 08:38 AM

Yes I could at that, tomorrow.
First :beer: :D

quest for silence 05-05-2016 09:01 AM

Quote:

Originally Posted by -The_Mask- (Post 124731)
There is only one thing certain in life and that is that you die. ;))

you = royal/generic you!?! :lol:


Quote:

Originally Posted by -The_Mask- (Post 124731)
That should be more then low enough for a 3,3V, 5V and 12V UVP trigger point. You can normally find the UVP trigger point in the datasheet of the secondary protection IC. If it doesn't work it probably means it isn't implemented the right way.

If it should be more than enough, should we think that the Leadex Gold 550W had not properly implemented UVP?


Quote:

Originally Posted by -The_Mask- (Post 124731)
Geen idee wat dat betekent. ;)

Sorry mate: it means Pares cum paribus facillime congregantur :D


Quote:

Originally Posted by -The_Mask- (Post 124736)
First :beer: :D

It's not friday: is there some party there? ;)

jonnyGURU 05-05-2016 11:58 AM

Stickied...

-The_Mask- 05-05-2016 01:40 PM

Quote:

Originally Posted by quest for silence (Post 124737)

It's not friday: is there some party there? ;)

Liberated from the Germans today. :D

quest for silence 05-05-2016 03:33 PM

Quote:

Originally Posted by -The_Mask- (Post 124745)
Liberated from the Germans today. :D

So you were no more congregantur. :beer: :D

GI_Joe 05-05-2016 10:00 PM

Quote:

Originally Posted by -The_Mask- (Post 124716)
But at least 1ms before the output voltages of the PSU go out of spec the PSU should drop the Power OK signal.

No, the PSU's eventually existing OVP and/or UVP protections would cause it to shut own into Latch mode. If no such protections, the PC's components would receive the out of spec voltages for as long as they can without shutting down/blowing up themselves. For the MBU and GPU, their VRMs would try to regulate the out of spec voltages for as long and much as they can.

Quote:

What's the problem then?
Some PSU don't drop the Power OK before the output voltages of the PSU go out of spec. This isn't good because it puts a lot of stress on the components of the PC that are powered by the PSU and now getting voltages that are outside of spec.
The PG signal is not a protection. It is a "not that simple" "HELLO" from the PSU to the MBU, which has to answer that with a "I am awake". THEN only, the PSU releases its output in PS_ON mode, no matter how good or bad that output is, that is monitored by protections.
Your explanation mixes too much the purposes of PG & PS_On and their causes and effects. There is a whole lot more to it than I have time to write here.

Quote:

But there is something else you should know!
Hold-up time is measured at full load!
:rolleyes: Reality is different. The important thing here is the overall AC capacitance in use and not some paper spec hold-up time claim.
Quote:

Almost no one loads his of her PSU till full load. And even if someone does, the chance that PSU is working at full load if the power fails, is almost zero.
Gamers can do and it simply depends. Most users do not have long-enough brown-outs, but some do. short brown-outs are common in the USA for example. And don't get me started on India's power grid :D

Quote:

So it actually isn't a problem?
For most people not no. ;)
Again, it depends if you want to risk a restart.

What happens in a brown-out is that the PSU must "power" the system from the AC power stored its main capacitor. IF that power is exhausted, the system restarts and THEN PG signal hello & back from PSU & MBU is started and the outputs released into PS_On.


Long story short, Don't mix signals and protections and their criss-cross causes and effects :D

sith'ari 05-06-2016 04:59 AM

What i want you to make us clear, is your opinion, if whether the "Power_OK signal-Hold UP time tests" that are being conducted by Aris & Pavel, are complete/thorough/useful as they are, or if they should probably measure something else as well ?? (*again, according to your opinion):confused:

GI_Joe 05-06-2016 05:19 AM

De-rating + UPS compatibility, if UPS are common in your region


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