| Table of Contents |
|---|
| 1. What Is VA and Why It Matters |
| 2. How to Calculate the Right VA for Your Inverter |
| 3. Need Help? Contact Okaya Support |
When there's a power cut, your inverter takes center stage. But many users still ask a basic but important question: what VA rating do I actually need? Getting this one number right is what decides whether your inverter runs your home smoothly or shuts down under load.
VA stands for Volt-Ampere — a unit used to measure how much electrical load an inverter can handle at one time.
Let's simplify:
If your VA is too low, your inverter will overload and shut down. If it's too high, you'll spend more than necessary on capacity you don't use. The right VA ensures smooth operation without overload, which makes it the most critical number to get right when choosing an inverter for your home.
Here's the simplest way to determine what VA rating you need — this is also the calculation behind tools like an inverter capacity calculator or an inverter load calculation formula:
VA = Total Wattage of Appliances ÷ Power Factor (typically 0.8 for home inverters)
Example:
Let's say you want to run 2 fans (80W each), 4 LED lights (15W each), and a TV (100W):
Total = (80 × 2) + (15 × 4) + 100 = 370W
Now: 370 ÷ 0.8 = ~463 VA
In this case, a 700 VA inverter for home (ATSW 950) is the safe and practical choice. Always select the next suitable available VA rating above your calculated requirement to provide headroom for appliance starting surges and normal load variation. This calculation is the key to selecting the right inverter — not guesswork or generic advice.
If you'd rather work from home size and rooms than a wattage list, our BHK-based inverter sizing guide walks through that scenario-based approach instead.
Okaya Home UPS Models and What They Support
Okaya's Advanced Home UPS range uses Advanced True Sine Wave (ATSW) technology and is built for small and medium homes. Here's what each model typically supports:
|
Model |
VA Rating |
Ideal For |
Appliances It Can Run |
|
ATSW 950 |
700 VA |
1BHK basic |
2 fans, 2-3 LED lights |
|
ATSW 1175 |
925 VA |
1BHK smart |
2 fans, 4-5 lights, Wi-Fi, TV |
|
ATSW 1400 |
1150 VA |
2BHK starter |
3 fans, 5 lights, Wi-Fi, TV, laptop |
|
ATSW 1700 |
1450 VA |
2BHK + kitchen |
Fans, lights, mixer, TV, router |
|
ATSW 1900 |
1650 VA |
2-3BHK usage |
Above + fridge |
|
ATSW 2550 |
2000 VA |
3BHK full load |
Fans, lights, fridge, TV, washing machine |
Appliance combinations shown above are indicative. Actual suitability depends on the combined running wattage and starting/surge load of the appliances being operated simultaneously.
These models are ideal for everyday residential use where clean power and smooth performance matter. You can explore Okaya's full inverter wattage and size guide to compare all Home UPS models side by side, or browse the range directly on shop.okaya.in.
Okaya Hi-Capacity UPS for Bigger Loads
If you need to support heavier appliances or run equipment in an office, shop, or clinic, Okaya's high-capacity inverter range is built for that.
|
Model |
VA Rating |
Ideal For |
Appliances It Can Run |
|
ATSW 3050 |
2500 VA |
3BHK heavy-duty home / shop |
TV, fridge, lights, mixer, kitchen appliances |
|
ATSW 3750 |
3200 VA |
Clinics, showrooms, offices |
Fans, desktops, printers, CCTV, Wi-Fi, POS systems |
|
ATSW 4550 |
4000 VA |
Labs, small factories, dental setups |
Deep freezer, dental chair, pumps, ACs (split), servers |
|
ATSW 6650 |
6100 VA |
Petrol pumps, critical setups |
Water pumps, compressors, telecom racks, multiple ACs, medical equipment |
Appliance combinations shown above are indicative. Actual suitability depends on the combined running wattage and starting/surge load of the appliances being operated simultaneously.
These models are suited to setups that require higher load handling, multi-battery configurations, and heavy-duty usage. Explore the full Hi-Capacity UPS range, or check the inverter and battery combo options if you're setting up a new system from scratch.
VA vs. Backup Time — Don't Confuse the Two
A higher VA inverter does not automatically mean longer backup. VA decides how much load the inverter can support at once; backup time depends separately on your inverter battery's capacity and health. Okaya batteries carry Certified Backup Hours (CBH) — tested runtime values verified by NABL-accredited laboratories — so you can check actual backup figures on the packaging instead of estimating them.
If you're still confused about which VA inverter or UPS model is right for your home or commercial setup, Okaya's expert team can help you understand your power needs and recommend a suitable inverter, battery, and setup.
You can reach out to our support team via WhatsApp at +91 9818909090, call us directly at +91 9818909090, or email us at care@okaya.in for personalised guidance.
Alternatively, you can visit your nearest Okaya-authorised inverter shop for face-to-face assistance. Go to okaya.in, open the Dealer Locator, and enter your location or pin code to find nearby Okaya-authorised dealers who can guide you on which inverter model fits your needs best.
Support is available both online and offline — choose what works best for you.
Conclusion
Choosing a VA inverter is not about guessing, overbuying, or copying what others are doing. It's about understanding your actual power need during an outage, applying one simple formula, and matching that with the right inverter model.
From compact Home UPS systems for 1BHK flats to Hi-Capacity UPS models for shops and clinics, Okaya offers a technology-led solution for every backup need, backed by verified VA ratings and Certified Backup Hours.
Frequently Asked Questions
What does VA mean in an inverter?
VA (Volt-Ampere) is the capacity of the inverter to handle electrical load. It shows how many appliances it can run at one time during a power cut — it is a measure of load, not runtime.
How do I know what VA inverter to buy?
Use this formula: total wattage of appliances ÷ 0.8 (power factor) = required VA. Always select the next suitable available VA rating above your calculated figure to provide headroom for appliance starting surges and normal load variation.
How is inverter wattage and capacity calculated for household use?
List the wattage of every appliance you want to run during an outage, add them together for total wattage, then divide by the power factor (typically 0.8) to get the required VA. This is the same method used by most inverter capacity calculators and load calculation formulas.
Does a higher VA inverter give longer backup?
No. VA is about load, not time. Backup time depends on the battery's capacity and health, not the inverter's VA rating.
How do I calculate inverter battery backup time?
Backup time depends on the battery's amp-hour (Ah) capacity and the actual load being run, not on the inverter's VA rating. Okaya batteries carry Certified Backup Hours (CBH) — tested and verified by NABL-accredited laboratories — printed on the packaging, so you can check a validated figure instead of estimating it.
Can I use a fridge or washing machine on Home UPS?
Yes. ATSW 1900 can support loads such as lights, fans, TV, refrigerator and mixer, while the higher-capacity ATSW 2550 can additionally support appliances such as a washing machine, subject to the combined running and starting load.
What is True Sine Wave technology?
It ensures smooth, consistent power delivery — safe for sensitive appliances like LED TVs, laptops, and routers. Okaya's current range uses Advanced True Sine Wave (ATSW) technology for this clean output.
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