continuous online dual conversion UPS

While reading some technical descriptions of specific UPS models, including user manuals, I have found that many describe a low voltage level at which
they "switch" or "transfer" from utility power to battery power.
For this kind of UPS, where even the utility power is always converted to DC and then back again to AC (inverter), why can't they do a combined capability in a low voltage situation in order to extend the battery as long as possible?
One type of low voltage scenario I have seen happen a few times is when the voltage is dropped to HALF the nominal voltage. The primary (pardon the pun) cause I understand for this is when a delta-wye transformer loses one phase on the primary side. Suppose phase B is lost. Phases A and C are still live. The delta primary A-C winding still has full voltage. However, the A-B and the B-C windings are in series fed from phases A and C. Given an equal load on the secondaries for A-B and B-C, this should divide the voltage in half for each. So 120/240 becomes 60/120, and 208Y/120 becomes 104Y/60.
At half the voltage, a UPS would want to draw twice the current to sustain the connected loads (maybe more if the circuitry operates at less efficiency in this condition). And that may be too much current. At some low voltage the current will exceed what the input should operate at.
So, when this low voltage condition exists, why not just go ahead and operate the AC to DC conversion at a level right at the current limit, and obtain the remaining power from the battery? By drawing less from the battery, and the most that is still safe from what can be gotten from the low utility voltage, the battery can last longer than it otherwise would. Is it too complex or costly to make an AC to DC conversion (basically a power supply) section that would operate on these lower voltages? Or is it too complex or costly to make one that can limit its operation to a specific current level?
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snipped-for-privacy@ipal.net wrote:

Another idiot idea from Phil. Why would you want the added complexity for a half assed idea that would make the unit more likely to fail? Why do you think CVTs are used on some systems? On second thought, do you ever think things through before starting one of your weird assed threads?
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On Tue, 03 Mar 2009 01:34:19 -0500 Michael A. Terrell
| | snipped-for-privacy@ipal.net wrote: |> |> While reading some technical descriptions of specific UPS models, including |> user manuals, I have found that many describe a low voltage level at which |> they "switch" or "transfer" from utility power to battery power. |> |> For this kind of UPS, where even the utility power is always converted to DC |> and then back again to AC (inverter), why can't they do a combined capability |> in a low voltage situation in order to extend the battery as long as possible? |> |> One type of low voltage scenario I have seen happen a few times is when the |> voltage is dropped to HALF the nominal voltage. The primary (pardon the pun) |> cause I understand for this is when a delta-wye transformer loses one phase |> on the primary side. Suppose phase B is lost. Phases A and C are still live. |> The delta primary A-C winding still has full voltage. However, the A-B and |> the B-C windings are in series fed from phases A and C. Given an equal load |> on the secondaries for A-B and B-C, this should divide the voltage in half |> for each. So 120/240 becomes 60/120, and 208Y/120 becomes 104Y/60. |> |> At half the voltage, a UPS would want to draw twice the current to sustain the |> connected loads (maybe more if the circuitry operates at less efficiency in |> this condition). And that may be too much current. At some low voltage the |> current will exceed what the input should operate at. |> |> So, when this low voltage condition exists, why not just go ahead and operate |> the AC to DC conversion at a level right at the current limit, and obtain the |> remaining power from the battery? By drawing less from the battery, and the |> most that is still safe from what can be gotten from the low utility voltage, |> the battery can last longer than it otherwise would. Is it too complex or |> costly to make an AC to DC conversion (basically a power supply) section that |> would operate on these lower voltages? Or is it too complex or costly to make |> one that can limit its operation to a specific current level? | | | Another idiot idea from Phil. Why would you want the added | complexity for a half assed idea that would make the unit more likely to | fail? Why do you think CVTs are used on some systems? On second | thought, do you ever think things through before starting one of your | weird assed threads?
You can't read. But then, you seem to have had this trouble for the past few years. I would speculate it has been a lifelong condition for you. I simply do not know if this was something that happened early in your life or just a few years ago, since I have not seen your writings prior to a few years ago.
The unit is more likely to fail if you let the battery carry the full load, instead of letting the battery share the load with what power it can get from the available mains voltage.
And I did not specify a particular design. If you want to discuss the failure modes of a particular design, then go ahead and spell out what that design is and we can discuss how and why it might fail (break down). If you do that, do keep in mind that it was your design, not mine.
If you want to assert a belief that no design is possible to do this, then by all means assert that. That will, of course, open you to the criticism that you are unable to come up with all possible designs, and MAY have missed one that would work well. You could defend against that by spelling out all the possible designs in advance.
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snipped-for-privacy@ipal.net wrote:

I have no problem reading and identifying moronic concepts.

Then the battery is too small, or too old. An overly complex design isn't the answer to crappy maintenance.

You didn't specify a design because you can't. It is another of your ignorant 'Gee Whiz!!!' ideas that won't work.

Its your stupid idea so its up to you to show us a design that will work while meeting all safety requirements, including isolation form the faulty power line, while continuing to draw power from it. How are you going to match the distorted waveform in real time, and adjust the voltage to what you need? Like I said in my first reply, "Why do you think CVTs are used on some systems?" but you didn't answer, because you don't know, or because it would prove this stupid scheme is worthless.
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On Tue, 03 Mar 2009 18:51:33 -0500 Michael A. Terrell
| I have no problem reading and identifying moronic concepts.
You have no skill in reading electrical enginering or technology. All the rest is fiction in your mind.
|> The unit is more likely to fail if you let the battery carry the full load, |> instead of letting the battery share the load with what power it can get from |> the available mains voltage. | | | Then the battery is too small, or too old. An overly complex design | isn't the answer to crappy maintenance.
It doesn't matter what the battery size is, small, medium, or large. If you power the loads entirely from the battery, it will last a shorter time than if you power the loads half from the battery and have from the mains.
|> And I did not specify a particular design. If you want to discuss the failure |> modes of a particular design, then go ahead and spell out what that design is |> and we can discuss how and why it might fail (break down). If you do that, do |> keep in mind that it was your design, not mine. | | | You didn't specify a design because you can't. It is another of your | ignorant 'Gee Whiz!!!' ideas that won't work.
Whether I can or not is irrelevant. I didn't try. So it doesn't matter. What I did was ask about the concept. You suggested it would fail, so you are the one that has a specific design in mind. YOUR DESIGN is a failure. You said so.
|> If you want to assert a belief that no design is possible to do this, then by |> all means assert that. That will, of course, open you to the criticism that |> you are unable to come up with all possible designs, and MAY have missed one |> that would work well. You could defend against that by spelling out all the |> possible designs in advance. | | | Its your stupid idea so its up to you to show us a design that will | work while meeting all safety requirements, including isolation form the | faulty power line, while continuing to draw power from it. How are you | going to match the distorted waveform in real time, and adjust the | voltage to what you need? Like I said in my first reply, "Why do you | think CVTs are used on some systems?" but you didn't answer, because you | don't know, or because it would prove this stupid scheme is worthless.
I came up with the basic concept. I didn't say I have a design that would work. I didn't say there has to be a design that worked. I ASKED ABOUT THE CONCEPT. YOU are convinced it cannot work, but YOU are completely unable to say why it would not work. Sounds to me like you are unwilling to disclose your design failure or whatever logic you came up with that suggests all the possible designs would fail. So what's left is your baseless assertion.
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snipped-for-privacy@ipal.net wrote:

Yawn. Another lame attempt to slur my name. The 'fiction' is that you believe the crap you dream up will work. What have you ever done in the real world? My design ideas are in space, aboard the ISS, used to track everything launched by NASA, the ESA, and by NOAA to track and control their LEO Weather Satellites. I also came up with the idea of uplinking a subcarrier channel to a C-band satellite from a different site than the main carrier. This was for United Video's microwave division for their EPG service on the WGN feed. It eliminated two leased phone lines from Salt Lake City where the mainframe computers were, to the WGN uplink in Chicago. It provided a more reliable service, and the savings of over $15,000 a month for the company I worked for.

If the battery size doesn't matter, then use eight AAA cells.

I didn't try to design anything, because your concept is so flawed. That is something you never see in the stupid crap you dream up. Your stupid idea would be dropped in ten seconds in a design review, and you would be told to clean out your desk.

You came up with another of your usual worthless ideas. If it was any good, you could buy a UPS with that technology. The design of UPS hardware is a mature field, so anything worthwhile has already been designed. Just because you get another harebrained idea means nothing.
Battery power for electronics has been used since the days of the early rotary dial telephones. Enough batteries to power everything for 15 to 20 minutes, that are float charged and used as filter capacitors. When the power failed, they started a gasoline or diesel powered generator. The exchange in my home town had a large generator for the exchange, and an old farm tractor with another alternator driven by the PTO for the office equipment, lighting and fans. the proper batteries with a good preventative maintenance program is better than your Rube Goldberg ideas.
have you ever seen the 'rectifier cabinets' used in telco central offices? You need a forklift to move them. With proper battery maintenance, the hardware and batteries last for decades
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wrote: | | snipped-for-privacy@ipal.net wrote: |> |> On Tue, 03 Mar 2009 18:51:33 -0500 Michael A. Terrell
|> |> | I have no problem reading and identifying moronic concepts. |> |> You have no skill in reading electrical enginering or technology. All the |> rest is fiction in your mind. | | | Yawn. Another lame attempt to slur my name. The 'fiction' is that | you believe the crap you dream up will work. What have you ever done in | the real world? My design ideas are in space, aboard the ISS, used to | track everything launched by NASA, the ESA, and by NOAA to track and | control their LEO Weather Satellites. I also came up with the idea of | uplinking a subcarrier channel to a C-band satellite from a different | site than the main carrier. This was for United Video's microwave | division for their EPG service on the WGN feed. It eliminated two | leased phone lines from Salt Lake City where the mainframe computers | were, to the WGN uplink in Chicago. It provided a more reliable service, | and the savings of over $15,000 a month for the company I worked for.
You could have made a lot more contributions to the world if you had the ability to read English and did not have the attitude of distorting what people say so you gain the ability to make assertions that are really false and lets you blame it on them. I'm not going to play your penis length game. There's no way to verify the truth or significance in anything you say.
Maybe you really did those things in the past and maybe they will work fine. But your brain is certainly not keeping up. Damaged?
|> |> The unit is more likely to fail if you let the battery carry the full load, |> |> instead of letting the battery share the load with what power it can get from |> |> the available mains voltage. |> | |> | |> | Then the battery is too small, or too old. An overly complex design |> | isn't the answer to crappy maintenance. |> |> It doesn't matter what the battery size is, small, medium, or large. If you |> power the loads entirely from the battery, it will last a shorter time than |> if you power the loads half from the battery and have from the mains. | | | If the battery size doesn't matter, then use eight AAA cells.
You are a complete lunkhead if you haven't figured out by now that this is about comparing the SAME SIZE BATTERY with 2 different wiring schemes, one where the battery carries the full load, and the other where the battery carries half the load. If YOU can't figure out the basic concept that when a battery only carries half the load, it runs longer, then I guess I need notify NASA, ESA, NOAA, that they might some flawed engineering running and their missions are at risk of things like premature battery failure. That is, if you aren't lying.
|> |> And I did not specify a particular design. If you want to discuss the failure |> |> modes of a particular design, then go ahead and spell out what that design is |> |> and we can discuss how and why it might fail (break down). If you do that, do |> |> keep in mind that it was your design, not mine. |> | |> | |> | You didn't specify a design because you can't. It is another of your |> | ignorant 'Gee Whiz!!!' ideas that won't work. |> |> Whether I can or not is irrelevant. I didn't try. So it doesn't matter. |> What I did was ask about the concept. You suggested it would fail, so you |> are the one that has a specific design in mind. YOUR DESIGN is a failure. |> You said so. | | | I didn't try to design anything, because your concept is so flawed. | That is something you never see in the stupid crap you dream up. Your | stupid idea would be dropped in ten seconds in a design review, and you | would be told to clean out your desk.
You think that the concept of running a battery at half load to extend its run time, relative to the same size battery running full load, is a flawed concept?
Now I have to say it ... what an utter moron.
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snipped-for-privacy@ipal.net wrote:

Keep throwing your hissy fits, Phil. You can't design anything, and continue to show the world what a fool you are.

That wasn't what you stated. You said the battery size doesn't matter, not how the same size battery was used. You claim I can't read, yet you can't even read what you wrote.

I never said that. I stated that a properly sized battery was need but as usual, you can't read and comprehend anything. Properly sized means that it has a reasonable reserve, and in exchange will give you a longer run time, if needed before the power is restored, or a backup generator comes on line. A larger battery is more reliable than the Rube Goldberg crap you come up with. You need to learn the KISS method if you want things to keep working.

We know you're a moron.

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wrote: | | snipped-for-privacy@ipal.net wrote: |>
wrote: |> |
|> |> |> |> On Tue, 03 Mar 2009 18:51:33 -0500 Michael A. Terrell
|> |> |> |> | I have no problem reading and identifying moronic concepts. |> |> |> |> You have no skill in reading electrical enginering or technology. All the |> |> rest is fiction in your mind. |> | |> | |> | Yawn. Another lame attempt to slur my name. The 'fiction' is that |> | you believe the crap you dream up will work. What have you ever done in |> | the real world? My design ideas are in space, aboard the ISS, used to |> | track everything launched by NASA, the ESA, and by NOAA to track and |> | control their LEO Weather Satellites. I also came up with the idea of |> | uplinking a subcarrier channel to a C-band satellite from a different |> | site than the main carrier. This was for United Video's microwave |> | division for their EPG service on the WGN feed. It eliminated two |> | leased phone lines from Salt Lake City where the mainframe computers |> | were, to the WGN uplink in Chicago. It provided a more reliable service, |> | and the savings of over $15,000 a month for the company I worked for. |> |> You could have made a lot more contributions to the world if you had the |> ability to read English and did not have the attitude of distorting what |> people say so you gain the ability to make assertions that are really false |> and lets you blame it on them. I'm not going to play your penis length |> game. There's no way to verify the truth or significance in anything you |> say. |> |> Maybe you really did those things in the past and maybe they will work fine. |> But your brain is certainly not keeping up. Damaged? | | | Keep throwing your hissy fits, Phil. You can't design anything, and | continue to show the world what a fool you are.
What did you think I designed?
You're the one that doesn't understand how to extend the life of a battery by reducing its load.
|> |> |> The unit is more likely to fail if you let the battery carry the full load, |> |> |> instead of letting the battery share the load with what power it can get from |> |> |> the available mains voltage. |> |> | |> |> | |> |> | Then the battery is too small, or too old. An overly complex design |> |> | isn't the answer to crappy maintenance. |> |> |> |> It doesn't matter what the battery size is, small, medium, or large. If you |> |> power the loads entirely from the battery, it will last a shorter time than |> |> if you power the loads half from the battery and have from the mains. |> | |> | |> | If the battery size doesn't matter, then use eight AAA cells. |> |> You are a complete lunkhead if you haven't figured out by now that this is |> about comparing the SAME SIZE BATTERY with 2 different wiring schemes, one |> where the battery carries the full load, and the other where the battery |> carries half the load. If YOU can't figure out the basic concept that when |> a battery only carries half the load, it runs longer, then I guess I need |> notify NASA, ESA, NOAA, that they might some flawed engineering running and |> their missions are at risk of things like premature battery failure. That |> is, if you aren't lying. | | | That wasn't what you stated. You said the battery size doesn't | matter, not how the same size battery was used. You claim I can't read, | yet you can't even read what you wrote.
And the statement is correct. The size does not matter for the principle to apply. If you understood what the principle is, maybe then you would understand that it works no matter what size of battery is involved. If the load on the battery is reduced, it will last longer.
|> |> |> And I did not specify a particular design. If you want to discuss the failure |> |> |> modes of a particular design, then go ahead and spell out what that design is |> |> |> and we can discuss how and why it might fail (break down). If you do that, do |> |> |> keep in mind that it was your design, not mine. |> |> | |> |> | |> |> | You didn't specify a design because you can't. It is another of your |> |> | ignorant 'Gee Whiz!!!' ideas that won't work. |> |> |> |> Whether I can or not is irrelevant. I didn't try. So it doesn't matter. |> |> What I did was ask about the concept. You suggested it would fail, so you |> |> are the one that has a specific design in mind. YOUR DESIGN is a failure. |> |> You said so. |> | |> | |> | I didn't try to design anything, because your concept is so flawed. |> | That is something you never see in the stupid crap you dream up. Your |> | stupid idea would be dropped in ten seconds in a design review, and you |> | would be told to clean out your desk. |> |> You think that the concept of running a battery at half load to extend its |> run time, relative to the same size battery running full load, is a flawed |> concept? | | I never said that. I stated that a properly sized battery was need | but as usual, you can't read and comprehend anything. Properly sized | means that it has a reasonable reserve, and in exchange will give you a | longer run time, if needed before the power is restored, or a backup | generator comes on line. A larger battery is more reliable than the | Rube Goldberg crap you come up with. You need to learn the KISS method | if you want things to keep working.
Whatever size you have, if the load is reduced, the battery runs longer. If you do ever need it to run that long, maybe you got a too large battery.
The real world involves UPSes that in most cases have limitations on the battery size, while the market wants longer run times. The "proper sizing" is just not something that is easily doable. That's a concept that applies when setting up large scale batteries with separate chargers and inverters. And I've done that for two mainframe data centers.
|> Now I have to say it ... what an utter moron. | | | We know you're a moron.
You've proven your ignorance.
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snipped-for-privacy@ipal.net wrote:

Absolutely nothing that has ever worked.

Bullshit. I stated several times in this thread about choosing the proper capacity which isn't using them at 99% of their rated capacity. I am a firm believer in properly de-rating a design so it is never stressed beyond reason, but your blind ignorance forces you to ignore what anyone tells you.
As you can see a few lines down I stated : Then the battery is too small, or too old. An overly complex design isn't the answer to crappy maintenance. then you tell me I would chose too small of a battery, once again proving you have zero comprehension of anything you read.

Sigh. You can't even tell there is anything outside the box, can you?

Whoopee. Two whole jobs. Get back to me when you know what your trying to do. y starting with say 50% extra batter capacity, they will last longer, and still be usable as they start to degrade, as well as handle surges if something has to be restarted while the system is running on the UPS.

Phil, you are a world class ignoramus who lives to put layer after layer of cheap lipstick on the pigs you dream up. Your other hobby is separating fly shit from pepper, under a broken microscope.
Keep showing everyone what a fool you are. Some people enjoy watching you go down for the third time, so they can toss you a concrete life preserver.
No one expect you to ever learn anything or to admit what a fool you really are. You make Roy look smart, by comparison.
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wrote: | | snipped-for-privacy@ipal.net wrote: |>
wrote: |> |
|> |> |> |> In alt.engineering.electrical Michael A. Terrell
|> |> |
|> |> |> |> |> |> On Tue, 03 Mar 2009 18:51:33 -0500 Michael A. Terrell
|> |> |> |> |> |> | I have no problem reading and identifying moronic concepts. |> |> |> |> |> |> You have no skill in reading electrical enginering or technology. All the |> |> |> rest is fiction in your mind. |> |> | |> |> | |> |> | Yawn. Another lame attempt to slur my name. The 'fiction' is that |> |> | you believe the crap you dream up will work. What have you ever done in |> |> | the real world? My design ideas are in space, aboard the ISS, used to |> |> | track everything launched by NASA, the ESA, and by NOAA to track and |> |> | control their LEO Weather Satellites. I also came up with the idea of |> |> | uplinking a subcarrier channel to a C-band satellite from a different |> |> | site than the main carrier. This was for United Video's microwave |> |> | division for their EPG service on the WGN feed. It eliminated two |> |> | leased phone lines from Salt Lake City where the mainframe computers |> |> | were, to the WGN uplink in Chicago. It provided a more reliable service, |> |> | and the savings of over $15,000 a month for the company I worked for. |> |> |> |> You could have made a lot more contributions to the world if you had the |> |> ability to read English and did not have the attitude of distorting what |> |> people say so you gain the ability to make assertions that are really false |> |> and lets you blame it on them. I'm not going to play your penis length |> |> game. There's no way to verify the truth or significance in anything you |> |> say. |> |> |> |> Maybe you really did those things in the past and maybe they will work fine. |> |> But your brain is certainly not keeping up. Damaged? |> | |> | |> | Keep throwing your hissy fits, Phil. You can't design anything, and |> | continue to show the world what a fool you are. |> |> What did you think I designed? | | | Absolutely nothing that has ever worked.
With respect to this thread, I did not design anything. So I guess you have actually made a statement that would evaluate as true.
|> You're the one that doesn't understand how to extend the life of a battery |> by reducing its load. | | | Bullshit. I stated several times in this thread about choosing the | proper capacity which isn't using them at 99% of their rated capacity. | I am a firm believer in properly de-rating a design so it is never | stressed beyond reason, but your blind ignorance forces you to ignore | what anyone tells you.
When have you ever designed a UPS that is in commercial production? Guess what. They don't do this. They can't. The reason they can't is because needs vary so widely. The best they can do is make a range of designs and let the buyer select what will most closely fit their needs.
| As you can see a few lines down I stated : Then the battery is too | small, or too old. An overly complex design isn't the answer to crappy | maintenance. then you tell me I would chose too small of a battery, | once again proving you have zero comprehension of anything you read.
What I stated is a fact that follows across all sizes, ratings, and ages of common batteries. Your statements don't even address it at all. You have no comprehension of what is being discussed. As I have said before in other past threads, your difficulty is comprehending English well enough to realize what people are talking about.
|> Whatever size you have, if the load is reduced, the battery runs longer. |> If you do ever need it to run that long, maybe you got a too large battery. | | | Sigh. You can't even tell there is anything outside the box, can | you?
Specify what box you are referring to.
|> The real world involves UPSes that in most cases have limitations on the |> battery size, while the market wants longer run times. The "proper sizing" |> is just not something that is easily doable. That's a concept that applies |> when setting up large scale batteries with separate chargers and inverters. |> And I've done that for two mainframe data centers. | | | Whoopee. Two whole jobs. Get back to me when you know what your | trying to do. y starting with say 50% extra batter capacity, they will | last longer, and still be usable as they start to degrade, as well as | handle surges if something has to be restarted while the system is | running on the UPS.
I never said anything about "50% extra batter capacity". Your failure to understand what you read is in play, again.
I referred to reducing the load on the battery by 50%. That means a battery with linear runtime characteristics (a hypothetical battery that merely approximates real life battery performance) would run twice as long. That isn't "50% extra batter capacity". It *IS* effective a 100% extra UNIT capacity when considering one unit with the feature I suggested against a unit without, when they each have the same battery.
Of course real batteries are non-linear with respect to runtime, and vary with other factors like aging, wear (number of cycles), temperature, and rate of usage (the power drawn from it).
|> |> Now I have to say it ... what an utter moron. |> | |> | |> | We know you're a moron. |> |> You've proven your ignorance. | | | Phil, you are a world class ignoramus who lives to put layer after | layer of cheap lipstick on the pigs you dream up. Your other hobby is | separating fly shit from pepper, under a broken microscope. | | Keep showing everyone what a fool you are. Some people enjoy watching | you go down for the third time, so they can toss you a concrete life | preserver. | | No one expect you to ever learn anything or to admit what a fool you | really are. You make Roy look smart, by comparison.
I'm only showing what a fool you are.
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snipped-for-privacy@ipal.net wrote:

You are so stupid that you hav enver hear of "Thinking outside the box"?

No, I SAID THAT I WOULD USE A BATTERY BANK 50% MORE THEN THE MINIMUM TO EXTEND ITS LIFE.

Tell me, Phil, how low of a line voltage do you expect your fantasy UPS to work, without being completely on batteries?
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wrote:
|> their needs. |> |> | As you can see a few lines down I stated : Then the battery is too |> | small, or too old. An overly complex design isn't the answer to crappy |> | maintenance. then you tell me I would chose too small of a battery, |> | once again proving you have zero comprehension of anything you read. |> |> What I stated is a fact that follows across all sizes, ratings, and ages |> of common batteries. Your statements don't even address it at all. You |> have no comprehension of what is being discussed. As I have said before |> in other past threads, your difficulty is comprehending English well enough |> to realize what people are talking about. |> |> |> Whatever size you have, if the load is reduced, the battery runs longer. |> |> If you do ever need it to run that long, maybe you got a too large battery. |> | |> | |> | Sigh. You can't even tell there is anything outside the box, can |> | you? |> |> Specify what box you are referring to. | | | You are so stupid that you hav enver hear of "Thinking outside the | box"?
You are quite creative. You have that going for you.
I know about "Thinking outside the box". But you didn't specify that box as the one you were referring to before I asked you to.
|> |> The real world involves UPSes that in most cases have limitations on the |> |> battery size, while the market wants longer run times. The "proper sizing" |> |> is just not something that is easily doable. That's a concept that applies |> |> when setting up large scale batteries with separate chargers and inverters. |> |> And I've done that for two mainframe data centers. |> | |> | |> | Whoopee. Two whole jobs. Get back to me when you know what your |> | trying to do. y starting with say 50% extra batter capacity, they will |> | last longer, and still be usable as they start to degrade, as well as |> | handle surges if something has to be restarted while the system is |> | running on the UPS. |> |> I never said anything about "50% extra batter capacity". Your failure to |> understand what you read is in play, again. | | | No, I SAID THAT I WOULD USE A BATTERY BANK 50% MORE THEN THE MINIMUM | TO EXTEND ITS LIFE.
With some UPSes you can do that. With others, you can't.
I *AM* talking about a redesign (without yet doing that redesign) of the charging (AC to DC) component of the UPS so that it will get whatever power it can get from a deep brownout condition, and use that to charge the battery or supplement the use of the battery.
It is PLAUSIBLE to do this because switch mode power supplies, which are devices that convert AC to DC at one or more DC output voltages, can readily and easily be made to operate over a voltage range greater than 2:1. Most computer power supplies now do 100 to 240 volts AC continuous, without needing one of those "115/230" switches. Almost all my wall warts do this, too. If it can be done for 100 to 240, it could also be done for 50 to 120, and thus be within the range for the class of deep brownout I have seen about half the time. Or a 240 volt class UPS can be left at the 100 to 240 volt range. What will need to be done to accomodate this is to be sure the current at the low voltage can be handled, or be restricted/limited.
So really, I don't even need to design this. It has already been done.
|> I referred to reducing the load on the battery by 50%. That means a battery |> with linear runtime characteristics (a hypothetical battery that merely |> approximates real life battery performance) would run twice as long. That |> isn't "50% extra batter capacity". It *IS* effective a 100% extra UNIT |> capacity when considering one unit with the feature I suggested against a |> unit without, when they each have the same battery. |> |> Of course real batteries are non-linear with respect to runtime, and vary |> with other factors like aging, wear (number of cycles), temperature, and |> rate of usage (the power drawn from it). |> |> |> |> Now I have to say it ... what an utter moron. |> |> | |> |> | |> |> | We know you're a moron. |> |> |> |> You've proven your ignorance. |> | |> | |> | Phil, you are a world class ignoramus who lives to put layer after |> | layer of cheap lipstick on the pigs you dream up. Your other hobby is |> | separating fly shit from pepper, under a broken microscope. |> | |> | Keep showing everyone what a fool you are. Some people enjoy watching |> | you go down for the third time, so they can toss you a concrete life |> | preserver. |> | |> | No one expect you to ever learn anything or to admit what a fool you |> | really are. You make Roy look smart, by comparison. |> |> I'm only showing what a fool you are. | | | Tell me, Phil, how low of a line voltage do you expect your fantasy | UPS to work, without being completely on batteries?
At least one existing UPS can go down to 86 volts or lower for a 120 volt system. Switch mode power supplies are readily available for the 100 to 240 volt range (check your own computer(s) and see). Just build one big enough to drive the inverter and charge the battery. Front end it with a 120 volt to 240 volt transformer if you want to power it on 120 volts. Or just connect it to a 240 volt circuit.
If a switch mode power supply can be made to operate over a 100 to 240 volt range, then a similar design for a smaller voltage could do 50 to 120 volts if that is the desired system voltage.
Note that the 100 to 240 volt range is nominal. They do have a wider range to accomodate voltage variations of 5% or even 10%. Power supply specs I have seen often say they work down to 90 volts. And this is without looking for wider range ones. I bet a real electrical engineer would know how to make one handle 45 to 305 volts input AC with a reasonbly constant DC output at some voltage.
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snipped-for-privacy@ipal.net wrote:

Lame excuse.

We were talking a new design so that is a lame answer. Do I have do define 'Lame' as well?

Really? Then go buy it.

Is this fantasy supply for a single computer, or for a room full of servers? It makes a huge difference.
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wrote: | | snipped-for-privacy@ipal.net wrote: |>
wrote: |> | |> | You are so stupid that you hav enver hear of "Thinking outside the |> | box"? |> |> You are quite creative. You have that going for you. |> |> I know about "Thinking outside the box". But you didn't specify that |> box as the one you were referring to before I asked you to. | | | Lame excuse.
Factually accurate. Look back at what you posted (and did not include in your last post ... how convenient). It could have been any box.
|> | No, I SAID THAT I WOULD USE A BATTERY BANK 50% MORE THEN THE MINIMUM |> | TO EXTEND ITS LIFE. |> |> With some UPSes you can do that. With others, you can't. | | | We were talking a new design so that is a lame answer. Do I have do | define 'Lame' as well?
Maybe a new design. But I never said I designed it. I never even gave a design. Yet you acted as if I have provided a design.
Existing designs can be used if full power conversion is acceptable over the full voltage range, either 100 to 240 volts for a 240 volt system, or 50 to 120 volts for a 120 volt system. Power supplies (chargers, AC to DC converters, by any other name) are already designed with this wide of an input voltage range. The only change in design that might be needed is model specifics, such as a particular capacity or form factor. This is stuff electrical engineers frequently do, as evidenced by the myriad of products like this on the market.
Where a theoretical design change would be needed is when it is desired to have an upper limit on the current being drawn. At lower voltages this would mean less power is drawn. That would be needed, for example, when a nominal power of 1000 watts is working on a 120 volt circuit, and it is desired to limit the current at 12 amps to operate within the 80% single dedicated device rating on a 15 amp circuit. Down to 83.333 volts, the full power can be sustained. Below that voltage, the power level must be reduced to stay within the 12 amp limit. So at 50 volts, the power would be only 600 watts. If the load being powered is 1000 watts, then 400 watts has to come from the battery. But that's only 40% of what the battery could carry. If the load being powered is only 600 watts, then the battery has no load at all.
The above figured are based on a hypothetical 100% efficiency ONLY for the purpose of simplified explanation. In reality efficiency levels would vary around 90% to 96%. It would complicate the explanation to use those figures, and make it harder for some people to see what is going on. In a real product design case, it would be more complicated. That's the job of the engineer doing the actual design.
|> I *AM* talking about a redesign (without yet doing that redesign) of the |> charging (AC to DC) component of the UPS so that it will get whatever |> power it can get from a deep brownout condition, and use that to charge |> the battery or supplement the use of the battery. |> |> It is PLAUSIBLE to do this because switch mode power supplies, which are |> devices that convert AC to DC at one or more DC output voltages, can |> readily and easily be made to operate over a voltage range greater than |> 2:1. Most computer power supplies now do 100 to 240 volts AC continuous, |> without needing one of those "115/230" switches. Almost all my wall |> warts do this, too. If it can be done for 100 to 240, it could also be |> done for 50 to 120, and thus be within the range for the class of deep |> brownout I have seen about half the time. Or a 240 volt class UPS can |> be left at the 100 to 240 volt range. What will need to be done to |> accomodate this is to be sure the current at the low voltage can be |> handled, or be restricted/limited. |> |> So really, I don't even need to design this. It has already been done. | | | Really? Then go buy it.
I already have many such power supplies. What is not available is such a power supply in an integrated UPS.
|> | Tell me, Phil, how low of a line voltage do you expect your fantasy |> | UPS to work, without being completely on batteries? |> |> At least one existing UPS can go down to 86 volts or lower for a 120 volt |> system. Switch mode power supplies are readily available for the 100 to |> 240 volt range (check your own computer(s) and see). Just build one big |> enough to drive the inverter and charge the battery. Front end it with a |> 120 volt to 240 volt transformer if you want to power it on 120 volts. Or |> just connect it to a 240 volt circuit. |> |> If a switch mode power supply can be made to operate over a 100 to 240 volt |> range, then a similar design for a smaller voltage could do 50 to 120 volts |> if that is the desired system voltage. |> |> Note that the 100 to 240 volt range is nominal. They do have a wider range |> to accomodate voltage variations of 5% or even 10%. Power supply specs I |> have seen often say they work down to 90 volts. And this is without looking |> for wider range ones. I bet a real electrical engineer would know how to |> make one handle 45 to 305 volts input AC with a reasonbly constant DC output |> at some voltage. | | | Is this fantasy supply for a single computer, or for a room full of | servers? It makes a huge difference.
It will make a difference when one is being selected for deployment. While the concept would work across a wide capacity range, it would only be economical for a smaller scale. I estimate the practical limit would be around the 6kVA to 10kVA per room or building.
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snipped-for-privacy@ipal.net wrote:

Bull shit.

No, I didn't. In fact, you can't even write a decent set of specifications. That is the whole point. You post stupid ideas, with no groundwork.

The wide range units switch the input configuration, depending on the input voltage and under the control of a custom IC. It isn't a single wide range.

You have that backwards. The switching supply is designed to output a fixed voltage, and the lower the input voltage, the higher the input current. Also, it may be higher than expected, due to a distorted waveform at the AC input. It will attempt to provide the power required by the load, as the input current goes up. That is the major flaw in your half assed concept.

the losses also depend on operating temperature, battery condition, and the percentage the load represents of the UPS design allows. The harder you push it, the hotter it runs, and the higher the losses.

Then it doesn't exist, and you lied.

Really? Do you have any ideas what is required to build that abomination? I do know, and you won't like the answers.
Show us you know what you claim by describing what has to be done to make it operate the way you want, or admit that you are the moron you're know to be.
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wrote:
| snipped-for-privacy@ipal.net wrote: |>
wrote: |> |
|> |> |> |> In alt.engineering.electrical Michael A. Terrell
|> |> | |> |> | You are so stupid that you hav enver hear of "Thinking outside the |> |> | box"? |> |> |> |> You are quite creative. You have that going for you. |> |> |> |> I know about "Thinking outside the box". But you didn't specify that |> |> box as the one you were referring to before I asked you to. |> | |> | |> | Lame excuse. |> |> Factually accurate. Look back at what you posted (and did not include |> in your last post ... how convenient). It could have been any box. | | | Bull shit.
The creativity, again.
|> |> | No, I SAID THAT I WOULD USE A BATTERY BANK 50% MORE THEN THE MINIMUM |> |> | TO EXTEND ITS LIFE. |> |> |> |> With some UPSes you can do that. With others, you can't. |> | |> | |> | We were talking a new design so that is a lame answer. Do I have do |> | define 'Lame' as well? |> |> Maybe a new design. But I never said I designed it. I never even gave |> a design. Yet you acted as if I have provided a design. | | | No, I didn't. In fact, you can't even write a decent set of | specifications. That is the whole point. You post stupid ideas, with | no groundwork.
You said I designed it wrong. That is the same as you saying I designed it.
|> Existing designs can be used if full power conversion is acceptable over |> the full voltage range, either 100 to 240 volts for a 240 volt system, |> or 50 to 120 volts for a 120 volt system. Power supplies (chargers, AC |> to DC converters, by any other name) are already designed with this wide |> of an input voltage range. The only change in design that might be |> needed is model specifics, such as a particular capacity or form factor. |> This is stuff electrical engineers frequently do, as evidenced by the |> myriad of products like this on the market. | | | The wide range units switch the input configuration, depending on the | input voltage and under the control of a custom IC. It isn't a single | wide range.
Actually, it is a single wide range. This was verified directly with one of the manufacturers that offered both full range and switched range models. One thing they said is that extra cost of full range is so low, now, that it is reaching the savings of having fewer models. There is some threshold switching that takes place in many models to change characteristics to make it more optimal at different parts of the range. For one model I asked about, that change happens at 166 volts RMS.
|> Where a theoretical design change would be needed is when it is desired |> to have an upper limit on the current being drawn. At lower voltages |> this would mean less power is drawn. | | | You have that backwards. The switching supply is designed to output a | fixed voltage, and the lower the input voltage, the higher the input | current. Also, it may be higher than expected, due to a distorted | waveform at the AC input. It will attempt to provide the power required | by the load, as the input current goes up. That is the major flaw in | your half assed concept.
Again with the inability to read.
I previously in that same post described the normal case of a lower input voltage having a higher input current. Then I described here the special case of a current limit. Do you even understand what a current limit is? Maybe not.
When the current input is limited, and has reached the limit, then the power input goes down as the voltage goes down. Common power supplies just shut down at this point. As I said, this case is a "theoretical design change". But I guess you didn't read those words or even understand what they meant.
|> That would be needed, for example, |> when a nominal power of 1000 watts is working on a 120 volt circuit, and |> it is desired to limit the current at 12 amps to operate within the 80% |> single dedicated device rating on a 15 amp circuit. Down to 83.333 |> volts, the full power can be sustained. Below that voltage, the power |> level must be reduced to stay within the 12 amp limit. So at 50 volts, |> the power would be only 600 watts. If the load being powered is 1000 |> watts, then 400 watts has to come from the battery. But that's only 40% |> of what the battery could carry. If the load being powered is only 600 |> watts, then the battery has no load at all. |> |> The above figured are based on a hypothetical 100% efficiency ONLY for |> the purpose of simplified explanation. In reality efficiency levels |> would vary around 90% to 96%. It would complicate the explanation to |> use those figures, and make it harder for some people to see what is |> going on. In a real product design case, it would be more complicated. |> That's the job of the engineer doing the actual design. | | | the losses also depend on operating temperature, battery condition, | and the percentage the load represents of the UPS design allows. The | harder you push it, the hotter it runs, and the higher the losses.
I didn't intend to list everything. Thank you for adding to the list so others who read this have a more complete list.
|> |> I *AM* talking about a redesign (without yet doing that redesign) of the |> |> charging (AC to DC) component of the UPS so that it will get whatever |> |> power it can get from a deep brownout condition, and use that to charge |> |> the battery or supplement the use of the battery. |> |> |> |> It is PLAUSIBLE to do this because switch mode power supplies, which are |> |> devices that convert AC to DC at one or more DC output voltages, can |> |> readily and easily be made to operate over a voltage range greater than |> |> 2:1. Most computer power supplies now do 100 to 240 volts AC continuous, |> |> without needing one of those "115/230" switches. Almost all my wall |> |> warts do this, too. If it can be done for 100 to 240, it could also be |> |> done for 50 to 120, and thus be within the range for the class of deep |> |> brownout I have seen about half the time. Or a 240 volt class UPS can |> |> be left at the 100 to 240 volt range. What will need to be done to |> |> accomodate this is to be sure the current at the low voltage can be |> |> handled, or be restricted/limited. |> |> |> |> So really, I don't even need to design this. It has already been done. |> | |> | |> | Really? Then go buy it. |> |> I already have many such power supplies. What is not available is such |> a power supply in an integrated UPS. | | | Then it doesn't exist, and you lied.
The wide range power supplies do exist. So no new design is needed for the simple case of operating at 60 volts on a 120 volt system, other than scaling it down from 100-240 to 50-120, which would not be hard. The slightly harder design, which I am sure any experienced power supply designer can do, is the current limiting design. But you don't even understand what current limiting is, so you are way way out of the running for being able to design such a thing.
|> |> | Tell me, Phil, how low of a line voltage do you expect your fantasy |> |> | UPS to work, without being completely on batteries? |> |> |> |> At least one existing UPS can go down to 86 volts or lower for a 120 volt |> |> system. Switch mode power supplies are readily available for the 100 to |> |> 240 volt range (check your own computer(s) and see). Just build one big |> |> enough to drive the inverter and charge the battery. Front end it with a |> |> 120 volt to 240 volt transformer if you want to power it on 120 volts. Or |> |> just connect it to a 240 volt circuit. |> |> |> |> If a switch mode power supply can be made to operate over a 100 to 240 volt |> |> range, then a similar design for a smaller voltage could do 50 to 120 volts |> |> if that is the desired system voltage. |> |> |> |> Note that the 100 to 240 volt range is nominal. They do have a wider range |> |> to accomodate voltage variations of 5% or even 10%. Power supply specs I |> |> have seen often say they work down to 90 volts. And this is without looking |> |> for wider range ones. I bet a real electrical engineer would know how to |> |> make one handle 45 to 305 volts input AC with a reasonbly constant DC output |> |> at some voltage. |> | |> | |> | Is this fantasy supply for a single computer, or for a room full of |> | servers? It makes a huge difference. |> |> It will make a difference when one is being selected for deployment. |> While the concept would work across a wide capacity range, it would only |> be economical for a smaller scale. I estimate the practical limit would |> be around the 6kVA to 10kVA per room or building. | | | | Really? Do you have any ideas what is required to build that | abomination? I do know, and you won't like the answers.
You've shown you don't even understand many of the concepts. How could you possibly be able to design these things if you don't even understand what it is supposed to do? Yeah, I won't like the answer that you can't accomplish it, if I were in the business of making UPSes. I'd have to hire a different engineer.
| Show us you know what you claim by describing what has to be done to | make it operate the way you want, or admit that you are the moron you're | know to be.
I've already described what it needs to do. It needs to keep supplying DC power in such a way that the inverter fully operates at up to the rated inverter load, using all the DC power available from the converter, and gets else is needed (but no more than this) from the battery. I'm not talking about the circuit details. Those things have already been done in other things besides UPSes. This is just a product design (that's not the same as circuit design) and integration issue.
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snipped-for-privacy@ipal.net wrote:

What we used to do to power 2 way radio systems for police and fire systems is power the systems from batteries full time with a smart charger that is big enough and well filtered enough to power both the loads and charge the batteries. No switchover time, will charge the batteries even in brownout conditions.
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| snipped-for-privacy@ipal.net wrote: |> On Tue, 03 Mar 2009 01:34:19 -0500 Michael A. Terrell
|> | What we used to do to power 2 way radio systems for police and fire | systems is power the systems from batteries full time with a smart | charger that is big enough and well filtered enough to power both the | loads and charge the batteries. No switchover time, will charge the | batteries even in brownout conditions.
Lots of AC to DC converters, chargers, and power supplies, can work on a wide range of voltage coming in. If it is rated 100-240 volts, as most computer power supplies are, then connecting it to a 240 volt circuit gives you a LOT of deep brownout range. Just be sure the circuit has amperage capacity for the low voltage scenerio.
The question I have is whether it is something UPS makers can do. Based on ratings I have seen, they design for a limited amoutn of brownout. The ones in the Minuteman Endeavor series I was looking at had a low voltage cutout at 86 volts for the 120 volt models. That's not as much voltage range as computer power supplies. Maybe they could do better. Maybe it will cost $10 more and ruin their market advantage for the average consumer.
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On Mar 3, 2:03am, snipped-for-privacy@ipal.net wrote:

Yes. UPSes are designed as cheap as possible. Some have seen how cheap. Replacing a UPS is sometimes less expensive than replacing its battery. Why make it more complex and more expensive?
Second, UPS battery is charged by a power supply equivalent to a wall wart. To accomplish what you have suggested means that battery charging power supply must be larger: increased costs. Or it must have an even larger operating input voltage - again increased costs. Just another reason why it is not done.
Third, AC utilities providing voltages at that low level is a specification violation. It rarely happens. If detected, utility typically cuts all power off due to defects that might cause such low voltages. IOW a more complex UPS circuit and the larger battery charger would rarely prosper from such a condition. Better is to get you to buy a larger (more expensive) UPS - and keep this UPS as cheap as possible.
Fourth, if a low voltage condition exists, unstable AC power is best disconnected from equipment anyway. Maintaining voltage too low can be harmful to electric motors and to the distribution system. Therefore, when that defect is detected, reliability says better is to disconnect.
Fifth, a UPS is for saving data. Making the UPS more complex for a rare type of failure is not useful. If a UPS needed to operate longer, then the UPS is too small anyway. Better is to get you to buy the more expensive UPS with a bigger battery.
Those UPSes are designed to sell mostly on price - as cheap as possible. Why do anything to make its price higher? Five different reasons why the suggestion is not useful.
Michael is a technician. He knows what a technician knows - what to do. He often does not know why - what an engineer learns. Therefore he has a repeat habit of attacking others because he does not know why. Attacking others is trick often used to mask the posters technical naivety. Unfortunately it works because others see the insults and then believe the insulter. Rather than learn the facts, many instead believe the first one to post insults. It is also how Rush Limbaugh operates.
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