Red Shift (Mar 01 2011)


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Dena Wiltsie
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Message 1083245 - Posted: 3 Mar 2011, 18:21:29 UTC - in response to Message 1083075.

Keep in mind UPS's do need new batteries from time to time. ;)

And they really need to be exercised about once a month with a fairly deep discharge about twice a year.

Lead acid should not be cycled if possible because it shortens it's life. Some designs are better able to withstand cycling than others but they all age when discharged. Most other battery types do last longer if you cycle them.
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Profile Chris SProject donor
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Message 1083257 - Posted: 3 Mar 2011, 19:30:22 UTC

You do need to "condition" mobile phone batteries when new.

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Profile Bill Walker
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Message 1083370 - Posted: 4 Mar 2011, 2:01:23 UTC

SockGap, in North America one phase is 120V theoretical (115V in practice usually). The failure you describe would "only" be 230V to 240V here. In any case, properly designed circuit protection should catch either the 240V or 415V failure before a fire. Your biggest worry is frying people, not boxes or wires. The argument in favor of 115/120V is that failures are more benign, therefore us users can be more dumb. (We need all the help we can get here.)

Chris, it depends on the battery type, and what the manufacturer says. NiCad definitely needs conditioning when new, and then regular deep cycling, but newer lithium based batteries should be much more tolerant of abuse.
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Message 1083415 - Posted: 4 Mar 2011, 4:25:17 UTC - in response to Message 1083370.

SockGap, in North America one phase is 120V theoretical (115V in practice usually). The failure you describe would "only" be 230V to 240V here. In any case, properly designed circuit protection should catch either the 240V or 415V failure before a fire. Your biggest worry is frying people, not boxes or wires. The argument in favor of 115/120V is that failures are more benign, therefore us users can be more dumb. (We need all the help we can get here.)

That's fine for your basic domestic lines over there though most data/server centres where you are will still use 220-240V as its much more efficient. ;)

Chris, it depends on the battery type, and what the manufacturer says. NiCad definitely needs conditioning when new, and then regular deep cycling, but newer lithium based batteries should be much more tolerant of abuse.

But the majority of UPS's use SLA batteries (or in my case sealed maintenance free car batteries). :)

Cheers.
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Message 1083505 - Posted: 4 Mar 2011, 14:10:13 UTC - in response to Message 1083415.

--[snipped]--


That's fine for your basic domestic lines over there though most data/server centres where you are will still use 220-240V as its much more efficient. ;)

Chris, it depends on the battery type, and what the manufacturer says. NiCad definitely needs conditioning when new, and then regular deep cycling, but newer lithium based batteries should be much more tolerant of abuse.


But the majority of UPS's use SLA batteries (or in my case sealed maintenance free car batteries). :)

Cheers.


In Europe, they are upgrading, voltage from 220V to 240V, in steps of 2V and 3V,
every year, the advantage is more power (Watts), without having to increase
mm^2, of the power lines.

Many years ago, I always used a 12VDC to 220VAC, transistor/thyristor converter, when camping at a (remote) place without a 220V(AC) power socket.
And used a car or truck battery (Lead-Acid)or(SLA), only options in those days.

Lithium-Ion, still is expensive, but by far the best, compaired to Ni-Cad, which
do indeed need, a deep-cycle unload/load, from time to time.
And does need to be swapped, after 4 or 5 years.
Probably one of the reasons, why mobo's use Li-Ion batteries.


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Profile Gary CharpentierProject donor
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Message 1083549 - Posted: 4 Mar 2011, 17:07:52 UTC - in response to Message 1083415.

SockGap, in North America one phase is 120V theoretical (115V in practice usually). The failure you describe would "only" be 230V to 240V here. In any case, properly designed circuit protection should catch either the 240V or 415V failure before a fire. Your biggest worry is frying people, not boxes or wires. The argument in favor of 115/120V is that failures are more benign, therefore us users can be more dumb. (We need all the help we can get here.)

That's fine for your basic domestic lines over there though most data/server centres where you are will still use 220-240V as its much more efficient. ;)

Most likely they have 3 phase 208V or two phase 240/480V


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Message 1083561 - Posted: 4 Mar 2011, 17:51:35 UTC - in response to Message 1083505.
Last modified: 4 Mar 2011, 17:52:01 UTC

--[snipped]--

Probably one of the reasons, why mobo's use Li-Ion batteries.



Mmm, Fred: M/b's don't use Li-ion batteries, they use Lithium-Manganese di-oxide one-shot batteries, because the battery is only there to maintain the BIOS information. (very low drain, and only when the computer is off...)
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Message 1083600 - Posted: 4 Mar 2011, 20:01:01 UTC - in response to Message 1083180.

I've never had one "burp" the attached equipment due to a test cycle. Even when it is a deep (80~90%) test cycle. All our UPS are APC.


I deal with a few dozen APC UPSs at work and I've seen a faulty battery drop the load during a self test a few times... It seemed to have more to do with the batteries - the ones in some of our hotter cupboards had "dried out" (or at least expanded and cracked the plastic battery case) and were not working at all...

Obviously this is not a problem with the UPS. I wonder just how hot it gets in your power closets to crack the plastic cases.

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Tom95134
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Message 1083602 - Posted: 4 Mar 2011, 20:05:17 UTC - in response to Message 1083370.

SockGap, in North America one phase is 120V theoretical (115V in practice usually). <snip>

It hasn't been 120 volts in the United States for years, and years. The actual voltage is 117VAC based on a single phase of a three phase line.

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Message 1083639 - Posted: 4 Mar 2011, 21:39:52 UTC - in response to Message 1083602.

SockGap, in North America one phase is 120V theoretical (115V in practice usually). <snip>

It hasn't been 120 volts in the United States for years, and years. The actual voltage is 117VAC based on a single phase of a three phase line.

I believe the specification is +/- 5 Volts. The voltage at my house is almost always 120V.
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Message 1083695 - Posted: 5 Mar 2011, 1:04:21 UTC - in response to Message 1083600.

As some Valve Regulated Lead Acid (VLRA) batteries age, they experience a phenomenon known as plate growth. Excessive heat is not required for plate growth to occur. This makes the plastic battery case swell. In extreme cases, the cases crack and split. This is more common with the low cost, low capacity batteries. I've seen plate growth and cracked cases in small batteries (12 volt, 4 amperehours) up to larger batteries (12 volt, 100 amperehours). The latter units were about 100 pounds. The valves in these batteries are pressure relief devices to prevent the cell from building up pressure and exploding in abnormal conditions while keeping the water and electrolyte in the cell during normal operation.

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Message 1083838 - Posted: 5 Mar 2011, 5:02:35 UTC - in response to Message 1083505.

--[snipped]--

In Europe, they are upgrading, voltage from 220V to 240V, in steps of 2V and 3V,
every year, the advantage is more power (Watts), without having to increase
mm^2, of the power lines.

Now that is strange because in the UK we are supposed to be dropping from our traditional 240V to 230V to be in line with a common European standard.

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Message 1084058 - Posted: 5 Mar 2011, 8:46:39 UTC - in response to Message 1083838.

Now that is strange because in the UK we are supposed to be dropping from our traditional 240V to 230V to be in line with a common European standard.

Yep.
Here in Australia it used to be 240V, but a couple of years ago it was dropped to 230V to match some international standard.
Ah, here we go
"As of 2000, the mains supply voltage specified in AS 60038 is 230 V with a tolerance of +10% -6%.[4] This was done for voltage harmonisation"
World mains voltages.
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Message boards : Technical News : Red Shift (Mar 01 2011)

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