Re: more on saving during power out

George Graves wrote:
On Tue, 13 May 2008 14:13:15 -0700, Glorb wrote
(in article <f0208$482a046b$25565@xxxxxxxxxxxxxxxxx>):

Snit wrote:
"Glorb" <Glorb@xxxxxxx> stated in post 9f94$4829f8b0$21118@xxxxxxxxxxxxxxxxx
on 5/13/08 1:23 PM:

Keith Ream wrote:
Glorb wrote:
weedhopper wrote:
On a Windows Xp machine, work in progress CAN be saved during a power
outage.

I spoke to my brother again today, he said I was slightly incorrect
in passing you information last time. Sorry.

This is what he said;

"the current is constantly monitored by software and electronics in
the computer. When the voltage drops below a set value, the
software immediately saves all the work in memory to the program
that you are using. There is enough power available to do that if
the setpoint is correctly calibrated.

When the machine powers up again, the saved work would be in the
program that was open at the time.

The software also saves everything in memory at set intervals.

There is no additional hardware needed. The software changes certain
registry values.

This can currently be installed on Windows Xp machines."

The software is currently Beta only.

Sorry again, I hope this clears up any misconceptions I may have
given you. I am not a computer techie. I only use them.
The only way to save work during a power outage is with a UPS,
regardless of what kind of computer you have. When the computer gets
a signal from the UPS, it does a save and shuts down, before the UPS
runs out of power.
** Posted from http://www.teranews.com **
Is a battery backup the same thing as a UPS?
No. A UPS has a battery, but it sits between the A.C. line and your
computer, and when the power goes down, it makes A.C. voltage using the
power stored in the battery. It has an RS232 port to connect to the
computer to signal when the computer should shut down.

A battery backup is a battery attached directly to the internal D.C.
circuits of the computer, and that's not what's used for most commercial
or home PCs (not counting laptop computers).
As far as I knew they were the same:

<http://pcsupport.about.com/od/componentprofiles/p/ups_backup.htm>
-----
The UPS is Also Known As:
battery backup, uninterruptible power source
-----

I stand by what I wrote above.
** Posted from http://www.teranews.com **

The difference between a UPS and direct battery backup may seem subtle to some and even nit-picking, but it is actually two totally different approaches to the same problem.

An uninterruptable power supply (UPS) uses a battery, yes, but it doesn't use one directly, it uses the battery and a DC to AC converter to change the DC battery voltage (usually 12 volts, but it can be something else) to 120 V (in the USA & Canada), 60 Hertz mains power. The computer user merely plugs his computer's mains cord (AC cable) into the receptacle on the UPS unit and the UPS unit plugs into the wall. Normally, the AC coming out of the wall passes through the UPS box and on to the computer. Some of the AC is used by the UPS to maintain the battery's charge and most use lead-acid or gel-cell technology because the usage is a lot like that in a car or motorcycle battery and is an ideal application for this type of cell. When the power fails, the UPS instantly kicks over to battery whereby the DC/AC converter maintains the power line voltage so that the computer does not shut down at all. Depending upon battery size (capacity) the UPS can maintain computer operation for any amount of time from a few minutes to hours. Most UPS units for home computers have relatively small batteries in them and these usually come with some software to tell the computer (either via Ethernet or USB) that main power has failed. This software will then initiate the proper shutdown sequence for the computer: Save all work, close all open applications, and properly shut down the computer.

Battery Backup, OTOH, generally means that there are batteries powering the computer directly as in a laptop. Generally, desktop or server computers which use direct battery backup are designed to operate that way. In a normal desktop machine, the average computer uses any number of voltages. The hard drives, for instance, might need +5V as well as perhaps + and - 12 volts. The motherboard needs multiple voltages too. This means that if the device is designed for direct battery backup, it must be designed to either run off of a single battery voltage (like a laptop) or it needs to provide the different voltages required either by employing multiple batteries of different voltages or by using DC/DC converters to "make" the different required voltages from the single voltage of one battery. Either way, this is more expensive than a UPS and isn't done often. Battery backed systems make the most sense in applications where long-term continued operation (rather than programmed shutdown) is the goal. These would be mission-critical applications where the computer cannot be allowed to shut down for any reason and long-term UPS operation is impractical due to the inefficiency of the large-scale DC to AC line voltage conversion required. Also, direct battery backup rarely includes the monitor (unless we are talking laptops, here). Most of the time UPS systems also power the monitor so that the operator knows what's going on. At any rate whether to include the monitor or not is a choice with a UPS system, it's not with direct battery backup.

Hope this clears up the confusion to some extent.

Thank you for backing me up. You said the same thing as I did, but in more detail.

It's good to see someone here with more knowledge than one gathers by a quick glance at a Web site.








** Posted from http://www.teranews.com **
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