Answer / ananth

T = N.V.X / VA

T= Time in Hours
N = No. of batteries
V= Voltage of Battery
X= Amp-Hour of the Battery
VA= Load

Answer / subir kumar manna

numbers of battery * ah of battery /output kva*130
34*200 /160*130
6800/20800
0.32 hours .

Answer / bhushan

UPS / Invertor Battery Backup Time =
----------------------------------


Batt Voltage X No.of (Batteries) X Ah (Single Battery) /
Total Load (Watts) = No.Hours Backup


Example :- 12v X 20(Batteries) X 200Ah (Single Battery)
/ 6000 (Watts) = No.Hours Backup


48000 / 6000 Watts = 8 Hours Backup

Answer / dhruvendra

V*AH/VA

Answer / a. dutta

To get one hour battery backup:

BATTERY AH = 1000 × VA × PF /( NO. OF BATTERY × BATTERY
VOLTAGE × LOAD% × PF

Answer / sayyed fayyaz ahmed

Calculating the UPS and Battery Backup Time
Before calculating the Battery Backup, let us know a few
factors that vary battery backup.
For and UPS with 875Va we can us a maximum load of 640
watts 677Va we can us a maximum load of 540 watts
The main thing we should understand is that whatever may be
the UPS wattage the battery backup will not vary.
The battery backup will only vary depending on the battery
Ah and the Usage Load.
To calculate UPS backup, we have a simple formula.
UPS Backup = Battery Ah * (Volts/Load) * (1/Power Factor)
Example: Let us calculate the backup for a system UPS
Load is the usage power, suppose we are running a PC then
the load is around 300 watts
Power Factor varies for device to device, the average power
factor is 1.4
Voltage is the voltage of the battery.
For a single battery the voltage is 12v.
If the batteries are connected in a series Voltage = 12 *
no. of batteries.
Battery Ah is the battery ampere used for the ups,
System UPS battery AH is 7
Then Battery Backup = 7 * (12/300) * (1/1.4)
= 7 * (0.04) * (0.7)
= 0.19 hours
= 11.4 Minutes
Note: You can use the same formula for calculating the
battery backup for home UPS or an INVERTER.

Answer / narayanarao.s

back up( in hours)= system dc volts x AH rating(
battery)/kva(load)x system power factor.

Answer / balajiram

Time=ups efficiency*battery efficiency*battery low volts*battery AH/ups output(watts)

Answer / prabhu

Battery Backup= No.of Batteries X Voltage of the batteries X Capacity of the batteries X Pf (0.8) / Load in Watts

Answer / prakash dhanshetty

backup time=(kva rating*power factor)!dc low of system

How equivalent impedance is calculated in thevenin theorem?

0 Answers  

how can we change the rotating direction of single phase AC induction motors?

12 Answers   Heubach Colour, L&T, MNM Jain Engineering College,

why transformer measures in kva

4 Answers  

when a primary current injection test is required, it is accomplished by what?

3 Answers  

What is the relationship between the sending end and receiving end?

4 Answers  

Why we use modulus with voltage in stability equation that is P=[E][V]SIN@/X WHY VOLTAGE IS IN MODE VALUE WHAT IS THE REASON?

1 Answers   Bhel,

WHAT HAPPEN IF LT SUPPLY 415 V FED TO THE HT 3.3KV MOTOR

1 Answers  

What is turn ratio of a transformer?

0 Answers  

how to find 5 kilo meter long under ground 33 kv cable fault location if IR VALUE shows 0.05 M ohm @5000 volt.and cable fault locator shows some time fault distance 3 kilo meter ,3.7 kilo meter and some time 1 kilo meter? now how to find the fault location that where is leakage. note--it is tested with 5000 kv megger and insulation resistance is 0.05 M ohm. and some time 0.03 M ohm comes.

0 Answers   OPS,

In case of a synchronous generator carbon brushes, some brushes expire before the others. Why is so? When all the brushes are installed at the same time, why don't thee expire at the same time?

1 Answers  

What is E.M.F ?

6 Answers  

1.What do you mean by inductive and capacitive parts of an electric circuit. 2.What do you mean by decrease of inductane and capacitance of a network? Please dont give me the text book answer.3. What is class X ct and its applications?

2 Answers