ALLInterview.com :: Home Page            
 Advertise your Business Here     
Browse  |   Placement Papers  |   Company  |   Code Snippets  |   Certifications  |   Visa Questions
Post Question  |   Post Answer  |   My Panel  |   Search  |   Articles  |   Topics  |   ERRORS new
   Refer this Site  Refer This Site to Your Friends  Site Map  Bookmark this Site  Set it as your HomePage  Contact Us     Login  |  Sign Up                      
Google
   
 
Categories >> Engineering >> Electrical Engineering
 
 


 

 
 Civil Engineering interview questions  Civil Engineering Interview Questions (3148)
 Mechanical Engineering interview questions  Mechanical Engineering Interview Questions (3304)
 Electrical Engineering interview questions  Electrical Engineering Interview Questions (13469)
 Electronics Communications interview questions  Electronics Communications Interview Questions (2393)
 Chemical Engineering interview questions  Chemical Engineering Interview Questions (423)
 Aeronautical Engineering interview questions  Aeronautical Engineering Interview Questions (77)
 Bio Engineering interview questions  Bio Engineering Interview Questions (17)
 Metallurgy interview questions  Metallurgy Interview Questions (80)
 Industrial Engineering interview questions  Industrial Engineering Interview Questions (166)
 Instrumentation interview questions  Instrumentation Interview Questions (2407)
 Automobile Engineering interview questions  Automobile Engineering Interview Questions (107)
 Mechatronics Engineering interview questions  Mechatronics Engineering Interview Questions (38)
 Marine Engineering interview questions  Marine Engineering Interview Questions (45)
 Power Plant Engineering interview questions  Power Plant Engineering Interview Questions (81)
 Engineering AllOther interview questions  Engineering AllOther Interview Questions (1204)
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 ?    252 Yes 137 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 ?    184 Yes 132 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 ?    80 Yes 36 No
R.gopalakrishnan
 
Answer
# 4
UPS Backup=Battery Voltage*Battery Ah/Load (watt) 
Is This Answer Correct ?    83 Yes 43 No
Sss
 
Answer
# 5
UPS BACKUP TIME= NO OF BATTERY X AH OF BATTERY /OUTPUT KVA
X130
 
Is This Answer Correct ?    53 Yes 34 No
Subir Kumar Manna
 
Answer
# 6
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 ?    34 Yes 20 No
N.muthukumar
 
Answer
# 7
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
# 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 ?    37 Yes 26 No
Asela
 
Answer
# 9
UPS backup time= Ah of battery * no of battery/output kva * 130 
Is This Answer Correct ?    70 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 ?    6 Yes 4 No
Parameshwara.s
 

 
 
 
Other Electrical Engineering Interview Questions
 
  Question Asked @ Answers
 
why is corona loss greater in a stranded conductor as compared to a solid conductor ?   2
what is meant by leading or lagging power factor?like in capacitor power factor is leading and in inductor power factor is lagging   4
What is difference between miniture circuit breaker and module case circuit breaker up to 63Amp. MSPL 7
HOW TURNS RATIO TEST IS DONE IN THREE PHASE TRANSFORMERS?   1
WHY TRANSFORMERS ARE RATED IN 11KV 22KV 33KV Instead off 10kv 20kv 30kv   5
What is meant by soft starter used in motors?   3
What do you mean by distributed winding in alternators? how exactly is 3 phase power generated?   2
Ohm's law applicable for semi-conductors?   4
Can someone help me in the Below Quest on Earthing 1.Types of Earthing and Recommended for what use 2.What is the Pit value /Panel N -E value should be or within limit for RP and UPS .   1
how to calculate load if i have three phase & single phase connection from power transformer( in term of kw & kva).can i take single phase load/3 for total kw calculation   1
what is mean by live tank and dead tank in current transformers?   1
what's float charger and boost charger? why it's used? Rolls-Royce 2
 
For more Electrical Engineering Interview Questions Click Here 
 
 
 
 
 


   
Copyright Policy  |  Terms of Service  |  Articles  |  Site Map  |  RSS Site Map  |  Contact Us
   
Copyright 2013  ALLInterview.com.  All Rights Reserved.

ALLInterview.com   ::  KalAajKal.com