Sites: GlobalSpec.com | GlobalSpec Electronics | CR4 | Electronics360
Login | Register
The Engineer's Place for News and Discussion®

Previous in Forum: Circuit Breaker Parameter   Next in Forum: Capacitor Bank
Close

Comments Format:






Close

Subscribe to Discussion:

CR4 allows you to "subscribe" to a discussion
so that you can be notified of new comments to
the discussion via email.

Close

Rating Vote:







17 comments
Anonymous Poster

How to Size Battery Bank for UPS

09/26/2010 2:51 AM

Dear Sir's.

I need your help regarding how to size the battery bank for UPS. If i have a 225 KVA UPS, approx 200KW, effeciency of 0.93, input and output volts are 380 V, backup time is 3 , can some1 please guide me, how to calculate the Amp - hours needed for the 12v battery.

thanks and kind regards

Reply
Interested in this topic? By joining CR4 you can "subscribe" to
this discussion and receive notification when new comments are added.

Comments rated to be Good Answers:

These comments received enough positive ratings to make them "good answers".
Guru
Engineering Fields - Electrical Engineering - New Member United Kingdom - Member - New Member Engineering Fields - Electromechanical Engineering - New Member

Join Date: Aug 2010
Location: Under the Major Oak
Posts: 3427
Good Answers: 137
#1

Re: how to size the battery bank for ups.

09/26/2010 3:23 AM

12V battery?

Go and have a look at the manufacturers manual. You can't expect a precise answers here given the fact that we don't have the information!

__________________
Pessimists are rarely disappointed.
Reply
Anonymous Poster
#2
In reply to #1

Re: how to size the battery bank for ups.

09/26/2010 3:38 AM

Thanks for the kind suggestion and sorry for the confusion but above 12V battery means (6 cells per unit - lead acid).

can you more precisely tell me what information you need ??

Reply
Guru
Engineering Fields - Electrical Engineering - New Member United Kingdom - Member - New Member Engineering Fields - Electromechanical Engineering - New Member

Join Date: Aug 2010
Location: Under the Major Oak
Posts: 3427
Good Answers: 137
#3
In reply to #2

Re: how to size the battery bank for ups.

09/26/2010 3:47 AM

Make, model type/No. rating, etc.

Hang on though, if you can give that information you can contact the manufacturer yourself!

__________________
Pessimists are rarely disappointed.
Reply
Power-User
India - Member - design engineer Engineering Fields - Electrical Engineering - New Member United Arab Emirates - Member - New Member

Join Date: Feb 2010
Location: dubai,mangalore,bangalore.....
Posts: 149
Good Answers: 8
#4

Re: how to size the battery bank for ups.

09/26/2010 5:09 AM

This topic has been discussed for quite a few times......search cr4........the below link may be helpful

http://cr4.globalspec.com/thread/38821

__________________
shamith gambhir, electrical engineer
Reply
Anonymous Poster
#7
In reply to #4

Re: how to size the battery bank for ups.

09/26/2010 7:52 AM

Sir thankyou very much for your kind help, I got it what i was looking for.

thanks and kind regards

Reply
Guru

Join Date: May 2010
Posts: 572
Good Answers: 55
#13
In reply to #4

Re: how to size the battery bank for ups.

09/27/2010 9:46 AM

Good link. To further clarify: refer to post 9 in that thread -- some of the rest is wrong or misleading.

__________________
Si hoc signum legere potes, operis boni in rebus Latinis alacribus et fructuosis potiri potes!
Reply
Power-User
India - Member - New Member

Join Date: Jul 2010
Location: India
Posts: 149
Good Answers: 2
#5

Re: how to size the battery bank for ups.

09/26/2010 5:31 AM

Back up time 3 ????

minutes, hours....

Be precise.

__________________
When was last time you did something for first time.
Reply Off Topic (Score 5)
Anonymous Poster
#6
In reply to #5

Re: how to size the battery bank for ups.

09/26/2010 6:48 AM

sorry for the typo, its 3 hrs (180 mins)

Reply
Guru
Technical Fields - Technical Writing - New Member Engineering Fields - Piping Design Engineering - New Member

Join Date: May 2009
Location: Ketchikan, AK, USA
Posts: 14977
Good Answers: 564
#8

Re: How to Size the Battery Bank for ups.

09/26/2010 2:35 PM

That's gonna be a huge battery bank. Why not have generator backup? (Perhaps with a smaller battery bank for a few minutes for starting the generator.)

__________________
In vino veritas; in cervisia carmen; in aqua E. coli.
Reply
2
Guru

Join Date: Apr 2007
Location: Hyderabad, India
Posts: 550
Good Answers: 10
#9

Re: How to Size Battery Bank for UPS

09/26/2010 11:28 PM

Tons of info and free downloadable battery bank calculator available at: http://hbl.in/

__________________
Subramanyam
Reply Good Answer (Score 2)
Guru

Join Date: Apr 2007
Location: Hyderabad, India
Posts: 550
Good Answers: 10
#10

Re: How to Size Battery Bank for UPS

09/26/2010 11:32 PM

CR4 Admin - email address removed

From the Site FAQ: Do not post phone numbers or email addresses. The CR4 Admin will delete all phone numbers posted in threads or comments, and we strongly urge you not to put up email addresses.

__________________
Subramanyam
Reply Off Topic (Score 5)
Associate

Join Date: Sep 2010
Posts: 45
#11

Re: How to Size Battery Bank for UPS

09/27/2010 4:15 AM

The backup time is 3 minutes or 3 hours?.Please specify time

Reply
Commentator

Join Date: May 2010
Posts: 81
#12

Re: How to Size Battery Bank for UPS

09/27/2010 4:35 AM

Hello,

Have you considered other batteries available, like LiFePO4, large format Lithium Batteries.

LiFePO4, large format Lithium Batteries are safe and cost effective in long run.

Compared to Lead acid batteries, they have

  1. Small Volume
  2. Lower weight
  3. Rated at 3 C discharge and 3 C Charge ( compare this lead acid battery with C / 10 discharge and c /10 charge)
  4. Cycle life more that 2000 cycles at 100 % DOD (compare this with Lead acid having 180 cycles at 80% DOD)
  5. Round trip Columbus efficiency more than 95% (Compare this with Lead Acid having less than 60%)
  6. Lead is not environmentally friendly.
  7. Totally maintenance free and do not need acid protective installation

The more advanced Lithium batteries with anode / cathode material with more advanced chemistry are tested for 20,000 cycle life and 60 C charge / 100 C discharge.

We are introducing large format batteries LiFePO4 batteries in India for Mobile and stationary applications.

Regards

Madhav Chowdhary

SWEE Technologies

Pune City (India)

Reply
Anonymous Poster
#14
In reply to #12

Re: How to Size Battery Bank for UPS

09/27/2010 11:25 AM

What is the method used for charging a LifePO4 Battery ?

Constant current or constant voltage ?

Reply
Commentator

Join Date: May 2010
Posts: 81
#15
In reply to #14

Re: How to Size Battery Bank for UPS

09/27/2010 11:44 AM

Hi,

Combination of both

CCCV Charger, with temp sensing / protection

Regards

Madhav Chowdhary

Reply
Anonymous Poster
#16
In reply to #15

Re: How to Size Battery Bank for UPS

09/29/2010 10:19 AM

Do you have LiFePO4 batteries with 520 AH capacity or larger ?

Reply
Commentator

Join Date: May 2010
Posts: 81
#17
In reply to #16

Re: How to Size Battery Bank for UPS

09/29/2010 1:00 PM

Dear Sir,

We can provide you LiFePO4 Battery having 520 AH and larger capacity also.

Please contact, by email ( sweetechnologies at gmail dot com ) to have further discussion.

Thanking You.

With Regards

Madhav Chowdhary

SWEE Technologies

Pune City (India)

Reply
Reply to Forum Thread 17 comments
Interested in this topic? By joining CR4 you can "subscribe" to
this discussion and receive notification when new comments are added.

Comments rated to be Good Answers:

These comments received enough positive ratings to make them "good answers".
Copy to Clipboard

Users who posted comments:

Anonymous Poster (5); Happy singh (1); kvsubramanyam (2); madhavchowdhary (3); MoronicBumble (1); SHAMITHGAMBHIR1 (1); THOBIAS MABUGO (1); TonyS (2); Tornado (1)

Previous in Forum: Circuit Breaker Parameter   Next in Forum: Capacitor Bank
You might be interested in: Uninterruptible Power Supplies (UPS), Single Phase Uninterruptible Power Supplies (UPS)