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Question
How can calculate ups battery back up time?
 Question Submitted By :: Electrical-Engineering
I also faced this Question!!     Answer Posted By  
 
Answer
# 1
Battery back up time=Battery current at full load/Battery Ah 
Is This Answer Correct ?    246 Yes 132 No
G.shanmugam
 
Answer
# 2


As a thump rule,if we need 1 hrs backup from the 1 KVA UPS
12V/130AH is Required,For Example,10 KVA ON-Line
UPS,Battery-12V/65AH,26 nos.

BAck-up Time=Ah of the Battery*Total no of the
Battery/Output KVA*130
BAck-up Time=65*26/10*130
BAck-up Time=1.3
BAck-up Time=60~70 Mins(Approx)
 
Is This Answer Correct ?    179 Yes 131 No
Guest
 
 
 
Answer
# 3
SEE SUPPOSE IF I NEED 740 WATTS USAGE BACK UP TIME UP TO 3
HOURS, THAN I CAN CALCULATE LIKE THIS(EXAMPLE 1
PC@350WATTS,3 FANS@80X3=240WATTS& 3TUBE LIGHTS
@(40+10CHOKE)=50=150WATTS)TOTAL=740 WATTS REQUIRE,= 740
DIVIDED BY 12 V=(61.666667)>61 Ah per hourx3
ours=183Ahbattery,(180Ah Battery).now you have selected
battery & than select a UPS/inverter that is you can only
get 80% of your UPS/inverter.Ex;1000 watts Ups/inverter.that
will be always safe for you & ever.thanks.R.GOPALAKRISHNAN.
 
Is This Answer Correct ?    79 Yes 35 No
R.gopalakrishnan
 
Answer
# 4
UPS Backup=Battery Voltage*Battery Ah/Load (watt) 
Is This Answer Correct ?    78 Yes 41 No
Sss
 
Answer
# 5
UPS BACKUP TIME= NO OF BATTERY X AH OF BATTERY /OUTPUT KVA
X130
 
Is This Answer Correct ?    51 Yes 34 No
Subir Kumar Manna
 
Answer
# 6
You can calculate the max time to use a UPS with this
formula

T max = efectiv energi / average power of the energy

that min

T max = 1377 (this is a constant, it's so big because it's
calculate in seconds)* capacity of batery in volts 12V *
capacity of batery in amper's 10Ah or other valu * number
of moduls (number of bateris to use) / how mutch power you
want to consum in W

for exemple

I have 8 baterys with 12V and 10Ah and I want to standup a
computer with 300 W consum

so
1377*8*10*12/300 = 4406.4 seconds that min 4406.4/3600 =
1.2h

sorry for my english

best regards,
Claudiu from ROMANIA

The sours is
http://en.wikipedia.org/wiki/Uninterruptible_power_supply
 
Is This Answer Correct ?    27 Yes 14 No
Claudiu
 
Answer
# 7
ups backup time=battery AH*battery efficiency*no.of
batteries/ups capacity in kva*130*output power factor

for example:65*0.9*10/5*130*0.8=1.125

approximately:1hr 15min
 
Is This Answer Correct ?    32 Yes 20 No
N.muthukumar
 
Answer
# 8
nomber of battery * battery voltage * each battery AHR
(130AHR total/ nomber of battery)130/260* efficiancy 90
PERCENT/ tatal VR.

26*12*5*0.9/1000
1 HR AND 4 MINUTES
 
Is This Answer Correct ?    34 Yes 26 No
Asela
 
Answer
# 9
UPS backup time= Ah of battery * no of battery/output kva * 130 
Is This Answer Correct ?    68 Yes 64 No
Yogesh
 
Answer
# 10
Tell me on a 5 KVA UPS with 12 Batteries of 65 AH how many
hours of backup will I have on full load.
 
Is This Answer Correct ?    4 Yes 3 No
Parameshwara.s
 

 
 
 
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