External "UPS" battery advice

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Hi,

But in short, an UPS is essentially a battery .
An external battery that you plug into the outlet, then plug the computer to it. When there is electrical supply it charges its internal batteries and while also powering the computer. When power goes out, it uses the battery to continue providing power the computer for a few minutes. While this energy is not enough for continuing normal work, it's sufficient to let you save whatever you're doing and properly shut the system down. The computer continues receiving power even after the blackout.

Basically, the whole city goes dark but your computer will live for 10/15 minutes more, and in that time you can shut down everything as it should instead of being abruptly powered off.

My questions are :

1- I know "UPS" battery is plugged into the outlet and plug the computer to it. When there is electrical supply it charges its internal batteries and while also powering the computer. So, the External "UPS" battery will be always connected to outlet regardless of there is electrical supply or not(i.e. if the electricity was cut off and gone on again, then no need to manually unplug the UPS from the outlet, and let the computer plugged to outlet) .

2- I see that the largest UPS is 865 Watts /1500 VA.
How long can a larger UPS battery be lasting until it drains its power/charge while it is disconnected from the outlet, or there is no electrical supply, and while also powering one or more devices draining the power of that UPS?
 
Solution
What answer would make you happy? Check the load line at https://www.cyberpowersystems.com/products/ups/intelligent-lcd/cp1500avrlcd It runs for 15 minutes with an 8.5Ah battery. In theory that UPS should run for 15x100/8.5=176 minutes. Will it really run for that long? I don't think so, but 12 batteries in parallel should get it to run for quite a long time. Recharging them probably would be an issue because that UPS isn't designed to handle so many batteries. Supplying up to 100A to a UPS designed for 8.5A could be a real concern. Why don't you buy an industrial UPS that includes a 100Ah battery pack? It will be quite large, but it will meet your requirements and be safe.




Thanks a lot, My 9 points are quite a lot, but I think most of them need a short answer. Yes, I appreciate your precious time, and I don't want to disturb you. However, as you may see that my points are concerned about your replies, which I don't think that I can find an answer for them by googling them since I don't know for which wordings I should google. So, I am respectfully requesting you to be replying to my last points as much as you can in your free time.

1- NOTE: Battery is only charging a power of 12V via UPS system which will be connected/plugged to main power supply.
So, when there is uninterupted power, then UPS system will be inverting the battery power from 12V into the "220V"
As a result, why have you divided 400W over 12V to get 33Amp in " if I need to supply 400W to my computer, then a 12V battery pack has to supply 400/12=33Amps"

2- If I should buy a 100Ahr battery, then how long will it last? According to your math '400W/12V=33Amps', then if I think a 100Ahr battery will last (100 Amps/33Amps = 3 hours. if I want to pull/supply 400W to my computer?

3- You said "but they should specify an Amp-Hour rating (like 100Ahr). if it specifies 100A / 10hr, then it might be a 100Ahr battery that's supposed to be used for a 10A load (to give it a 10hr discharge time). that's quite common"
I think '100A/10hr' means battery will last 10 hours (100A/10hours = 10 hours). However, you said " if it specifies 100A / 10hr, then it might be a 100Ahr battery". How might "100A/10hr" be a 100Ahr? How could your calculated it? If I want to supply 400W for my computer from 100A/10hr, and accordnig to your math '400W/12V=33Amps', then 100Amps/33Amps = 3 hours. So, "100A/ 10hr" cannot be true(100Ambs cannot be lasting 10 hours) if I want to pull more than 10Ams/hour from it. since when did your math, I found a 100Ams only last 3 hours with pulling 33Amps from it?


4- Battery is measured by Amp-Hour rating (like 100Ahr)((have an Amp-Hour (Ahr) rating somewhere).However, I was told that UPS system/instrument should have an W-Hour (Whr) (like 4000W/4K), although in the user's manual for that NIPPOTEC External Battery UPS instrument I found in my own coutnry I have not found any W or K typed?

5- I really googled the UPS system, and the Battery, but I didn't find the same kind on the internet. This is strange.
Although I googled with these wordings:

From the User's Manual::

NIPPOTEC Externeal Battery UPS
Intelli Pure SINEWAVE Technology - Made in India.

Charging current: 10AMP - 14AMP
Instrument Description - Externeal Battery UPS:
Single Battery(12V) system
SW720, SW950, SW1125

Double Battery(24V) system
SW1650, SW 2000

SN No: 15FDMHFAD10201



6- From the User's Manual::[/ In the Technical Specificantions shown below in bold, "Output Voltage on USP mode 210V ± 10%". is strange.
I think output Voltage on USP mode must be 220V(Same as input) as long as my government main line. Or otherwise, my devices(laptop, desktop) powered by the UPS system, requiring a 220V, will damage ?

Model
SINEWAVE UPS: SW720 / SW950 / SW1125 /SW1650 / SW 2000
Input Voltage
100V~300V(standard input voltage range)

180V~260V(Narrow input voltage range)
Output Voltage on Mains mode
Same as input
Output Voltage on USP mode
210V ± 10%
Output frequency of UPS mode
50 Hz ± 0.1 Hz
Switching from Mains to UPS and from UPS to mains
Automatic
Output Waveform on Mains mode
Same as input
Output Waveform on UPS mode
PURE SINE WAVE
Battery charging current
Constant charging approx 10% of the rated battery current in Ah
Charger
Power Factor controlled Boost Technology
Efficiency
> 80%
UPS Overload/UPS short circuit
110% / 300%
USP Transfer Time
≤ 15 msec.
Technology
Digital Signal Controller(DSC) Based Intelligent Control Design
Auto Rest Feature
Yes


7- the battery is sold with made in China. But, I haven't found it on the internet. I haven't seen any company name on it.

8-as long as the price for a UPS system with model SW1125 is sold for $169.8 and the price for a Single Battery(12V) -- 100A/10 Hours is sold for $115.3. I think 169+115 = $284 is NOT reasonable price for a UPS system, and a battery?????

As a result, What about purchasing a generator with that price. At least the generator will work on diesel or petrol and can itself be generating power. However, the UPS equipment can only save/charge the battery with power, and then can invert power from the battery from 12V into 220V.

9- I noticed the UPS equipment is very large, and even the battery is so. So, these two pieces of equipment would need a wide area in a room.


 


I hope you would find a little bit of time to answer any points of mine you think would need to be answered.


 
1 - He's correct.

2- Certainly not. The UPS documentation specifies hoe long it will run.

3, 4 and 5 - Provide a link to the UPS and battery pack.

6 - No damage will occur if the UPS provides 210V. Where I live the voltage should be 120V, but my laptops will work at 105V without issues. Providing too much voltage is worse than not enough.

7 - You only care about the specs.

8 - Why isn't it reasonable?

9 - They are designed for computer rooms where space requirements are planned ahead of time.

What are your requirements (what will be connected to the UPS) and for how long does it need to run?
 


Thanks a lot,
If I had, I wouldn't have asked this points. I only provided the information printed on the user's manual in the UPS. However, battery doesn't have a user's manual.

 


6- The line power in my home country is 220V, so I am expecting that output of any UPS must be 220V. Or otherwise, my devices connected to UPS will damage since they all need 220V.
From the User's Manual:: In the Technical Specifications shown below in bold, "Output Voltage on USP mode 210V ± 10%". is strange.
I think output Voltage on USP mode must be 220V(Same as input) as long as my government main line. Or otherwise, my devices(laptop, desktop) powered by the UPS system, requiring a 220V, will damage ?. I also don't know what 210V ± 10%". means.

8- since the generator is priced with the same price of UPS and battery.
 
A battery has specs; it doesn't need a user manual. Look at the specs and you'll know for how long it can provide standby power. What's your UPS rating in watts or VA? What does it say on the battery or battery pack? What equipment will be connected to it, how much power will be drawn and for how long does the UPS has to provide power?

As an example, my Smart-UPS 1500 uses two 12V 18Ah batteries. According to APC, the typical backup time at half load is 23.9 minutes (490 Watts) and at full load it is 6.7 minutes. If you know the load and batteries, then you can figure out the expected backup time. Just bear in mind that older batteries are weaker and the backup time is reduced.
 


6 - 210V ± 10% means 210V ± 21V (189V - 231V).

8 - A cheap generator doesn't provide clean enough power for computers; you still need a UPS. At that price you are not referring to a generator like the ones installed for data centers.
 



Thanks a lot,
The battery rating is 100Ahr, 12V, which I think Watts = 100*12= 1200Whr.
However, for UPS equipment, there is no rating at all mentioned in the user's manual, except Charging current: 10AMP - 14AMP


From the User's Manual::

NIPPOTEC Externeal Battery UPS
Intelli Pure SINEWAVE Technology - Made in India.
Charging current: 10AMP - 14AMP
Instrument Description - Externeal Battery UPS:
Single Battery(12V) system
SW720, SW950, SW1125

Double Battery(24V) system
SW1650, SW 2000

SN No: 15FDMHFAD10201





Model
SINEWAVE UPS: SW720 / SW950 / SW1125 /SW1650 / SW 2000
Input Voltage
100V~300V(standard input voltage range)

180V~260V(Narrow input voltage range)
Output Voltage on Mains mode
Same as input
Output Voltage on USP mode
210V ± 10%
Output frequency of UPS mode
50 Hz ± 0.1 Hz
Switching from Mains to UPS and from UPS to mains
Automatic
Output Waveform on Mains mode
Same as input
Output Waveform on UPS mode
PURE SINE WAVE
Battery charging current
Constant charging approx 10% of the rated battery current in Ah
Charger
Power Factor controlled Boost Technology
Efficiency
> 80%
UPS Overload/UPS short circuit
110% / 300%
USP Transfer Time
≤ 15 msec.
Technology
Digital Signal Controller(DSC) Based Intelligent Control Design
Auto Rest Feature
Yes


So, my questions are:

Firstly: If I want to use that battery rating (100Ahr and 12V), and that UPS above, and I need to supply 400W to my computer, then I think a 12V, and 100Ahr battery pack has to supply 400W/12V=33Amps.
So, according to that math, how long should a 100Ahr battery be lasting powering my computer requiring 400Wh?.

I think according to the math '400W/12V=33Amps', then 100Amps/33Amps = 3 hours. So, a 100Ahr battery only last 3 hours with pulling 33Amps from it to power my computer requiring 400Whr.

Secondly: I googled that UPS with that information in bold above, but I couldn't find such UPS at all.
 
What UPS do you have? The SW720 won't discharge the battery since it will shutdown as soon as a power outage occurs. That being said, if the computer consumes 400 watts at the outlet (there is a difference between power draw from the PSU and from the outlet because no PSU is 100% efficient), then base the backup time expectations on a known UPS like the APC 1500VA: http://www.apc.com/shop/mk/en/products/APC-Smart-UPS-1500VA-LCD-230V/P-SMT1500I That UPS with a RBC7 cartridge (408 Volt-Amp-Hour) would be good for 33.3 minutes when the batteries are brand new. With a 1200 Volt-Amp-Hour battery pack, it would last 97.9 minutes.
 
no, it won't. SLA battery capacity isn't linear, and is only based on a discharge rate of C/20 or maybe C/10 at best. at C/3 the capacity tanks. i've mentioned this a few times before - look at the load lines.

// this is my last post in this INCREDIBLY long-winded thread
 
I know that, but why get into details and generate more questions? I simply based my answer on the graph provided by APC for a 1500VA UPS with an RBC7 battery pack. At a load of 40%, if one battery pack is good enough for 33 minutes, then in theory 3 battery packs in parallel should be good for 99 minutes. Besides the OP probably won't buy an expensive UPS with a 100Ah battery pack because they are large and expensive.
 


Thanks a lot,

1- I'd like to buy SW1125 UPS. But unfortunately, there is no rating written in the user's manual at all. Except, Charging current: 10AMP ~ 14AMP, which I don't know if it is rating for UPS or not.

2- I'd like to bury 100Ahr battery. So, since all battery saving power in 12V. So, the watt for battery would be 12V * 100A = 1200Whr.

3- How to know how long a battery would be lasting powering a computer with a 400 W?
If I want to use that battery rating (100Ahr and 12V), and that SW1125 UPS, and I need to supply 400W to my computer, then I think 100Ahr battery has to supply 400W/12V=33Amps.
So, according to that math above, how long should a 100Ahr battery be lasting powering my computer requiring 400Whr?.
I think a 100Ahr battery would be lasting 3 hours powering my computer requiring 400Whr
1200W/400W = 3 hours OR 100A / 33A = 3 hours
I think according to the math '400W/12V=33Amps', then 100Amps/33Amps = 3 hours. So, a 100Ahr battery only last 3 hours with pulling 33Amps from it to power my computer requiring 400Whr.

4- I googled this model SW1125 UPS with its information posted in bold before, but I couldn't find such a UPS at all.
 
It won't last for 3 hours; a UPS isn't very efficient at converting DC to AC. You could contact Nippotec in Dubai, U.A. for more info about it: http://nippotec.com/contact-us-2/ I know you are in a different country, but Nippotec should be able to answer your questions since your voltage and frequency are identical. Based on it's model number, I presume the UPS is 1125VA, but I may be wrong. The info that you provided clearly indicates that it uses a 12V battery pack; this means that you need to wires all batteries in parallel. You definitely need to ask if the UPS is designed to work with additional battery packs.

If you check this http://home.schneider-electric.com.my/en/documents/BR24BPG%20Brochure.pdf you'll see that APC can provide different expected runtime (33 minutes in one document and only 14 in this one). You better confirm how many batteries would the Nippotec require to meet your expectations.
 


Thanks a lot,
I need to know how the math to know how long a battery and UPS used last powering, for instance, a device "400W"?
For instance, if I have SW1125 UPS, and I have 100Ahr battery. So, since all batteries save power in 12V. So, the watt (AV) rating for the battery would be 12V * 100A = 1200Whr.

How to know how long a battery would be lasting powering a computer requiring a 400 W?
If I want to use that battery rating (100Ahr and 12V), and that SW1125 UPS, and I need to supply 400W to my computer, then I think 100Ahr battery has to supply 400W/12V=33Amps.
So, according to that math above, how long should a 100Ahr battery be lasting powering my computer requiring 400Whr?.
I think a 100Ahr battery would be lasting 3 hours powering my computer requiring 400Whr
1200W/400W = 3 hours OR 100A / 33A = 3 hours

I think according to the math '400W/12V=33Amps', then 100Amps/33Amps = 3 hours. So, a 100Ahr battery only last 3 hours with pulling 33Amps from it to power my computer requiring 400Whr.
 




Thanks a lot,
I don't know for what I need 56 Amps?

I understand from your comment there is no UPS perfect 100%. So, with UPS which is 60% efficient.
If I have SW1125 UPS and a 100Ahr battery, I want to supply 400W to my computer, what is the math to know how long a battery would last powering that device requires a power of 400W?
I think the math would be as follows (watts(AV) for the battery is divided by watts for device)

So, If I want to use a battery rating (100Ahr and 12V), then 'watt' for battery would be 100Ahr * 12V = 1200Whr
So, 1200W/400W= 3 hours. So, a 100Ahr battery would be lasting 3 hours powering my computer requiring 400W.

 


Thanks a lot,

1- You sometimes say PSU, although it should be UPS?

2- I think there is misunderstanding, if I have any battery, let me say a 100Ahr battery, and I have any UPS, let me say SW1125 UPS . So, when I want supply 400W for my computer to be powered by battery. Then, how long would that 100Ahr be last powering my computer?



I think the math would be as follows (watts(AV) for the battery is divided by watts for my computer)

then 'watt' for battery would be 100Ahr * 12V = 1200Whr
So, 1200W/400W= 3 hours. So, a 100Ahr battery would be lasting 3 hours powering my computer requiring 400W.
 
Let's be clear once and for all. A UPS is approximately 60% efficient at converting DC to AC. That being said, to provide 400W to the PSU, it requires 400/60*100=667W. You didn't tell us if 400W is at the outlet or from the PSU (Power Supply Unit). If it's from the PSU, then you also need to take into account its efficiency at that load; a crappy PSU that only is 75% efficient at 400W will draw 400/75*100=533W from the UPS. It would then draw 533/60*100=888W from the UPS. Your problem is that you assume 100% efficiency which is impossible.

BTW I don't confuse UPS and PSU (you may refer to it as a SMTP in your country).
 



Thanks a lot,
I want to plug my computer requiring 400W to the UPS. So, the computer will be powered by 100Ahr battery. So, I want to know how many hours that 100Ahr battery will last powering my computer.
1- But you didn't let it clear how many hours a 100Ahr battery can last powering my computer requiring a 400W while the government main power outage occurs and continues for a long time.


2- Who allowed '4Ryan6" to selecte the Spectre694's answer as the solution March 19, 2016 5:43:48 AM? I the one who created the topic cannot even cancel this selection.
 


LOOK

AT

LOAD

LINES

FOR

F'S

SAKE

!!!


you're asking the same stupid question again and again and again, and no matter how many times we told you THE MATH ISN'T LINEAR, YOU HAVE TO LOOK AT LOAD LINES, you keep asking about the perfect math and how to CALCULATE it.

you DON'T.

you LOOK AT THE FRIGGIN LOAD LINES. (load lines a.k.a. discharge curves)


jesus!!!
 


1 - Presume one hour because you won't tell us if 400W is power drawn from the outlet or the power drawn by the components from the PSU. You also didn't tell us what PSU you have, but it can greatly impact the backup time. You also seem to presume that a battery doesn't get weaker over time, but it does. Configure the software that should be provided with the UPS to shutdown the PC after a power outage that lasts more than n minutes and you'll be safe. You also need to take into account that once the battery is almost discharged, another power outage could occur and then the UPS will shutdown without warning.

2 - I unselected it for you.

 


Thanks a lot,

1- Strange what you have outlined above.
Presume I have a say a computer plugged in and lose power then the UPS will automatically begin supplying battery power to the computer until either it runs out of battery or the line power comes back and it switches to line power again. Once back on line power it will automatically begin charging the battery.

So, if my computer requires a power of 400W to be running, so how many hours will UPS last to supply a 100Ahr battery power to the computer even it runs out of battery or line power comes back.



2- why are you asking about whether 400W is power drawn from the outlet or the power drawn by the components from the PSU.

3- I don't know there are many PSU(Power Supply Unites). So, why do you ask what PSU I have? What PSU do you want me to tell you about?
 
1 - If configured properly, the UPS shouldn't power up until the battery is charged at 50% or more. You obviously don't understand how a UPS works; depleted batteries can't provide backup until they are partially recharged and they can provide the expected backup time only once the recharge is complete (several hours).

2 - Because it makes a huge difference.

3 - Don't you know what PSU you have in the system that you want to protect?