UPS & Battery Backup Time Calculatorیو پی ایس بیک اپ ٹائم
Work out how long your UPS battery will last during load shedding, or how big a battery you need.لوڈ شیڈنگ میں یو پی ایس بیٹری کتنی دیر چلے گی، یا کتنی بڑی بیٹری چاہیے — معلوم کریں۔
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About this tool
Backup time = battery voltage × Ah × number of batteries × usable depth of discharge × inverter efficiency ÷ load in watts. Lead-acid (tubular) batteries last longer if regularly discharged only to about 50%, while lithium batteries can safely use about 90%.
A typical 12 V 200 Ah tubular battery running 300 W of fans and lights gives about 3 hours 24 minutes at 50% depth and 85% efficiency.
How to use it
- Enter your total load in watts.
- Choose battery type and inverter efficiency.
- Enter battery voltage, Ah and count — or switch to “battery size needed”.
Limitations
- Old batteries, heat and high loads reduce real backup.
Frequently asked questions
How many fans can a 200 Ah battery run?
About 3–4 ceiling fans (80 W each) for 3+ hours on a 50% discharge.
Why use only 50% of a lead-acid battery?
Deeper discharges shorten battery life significantly.
What size inverter do I need?
At least 25% above your peak load.
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