APC UPS Runtime Calculator
Use this tool to estimate the runtime of your APC UPS based on your equipment's power consumption. Enter your APC UPS capacity (VA) and the load in watts to calculate the estimated runtime during a power outage.
List of the Best APC UPS:
Understanding APC UPS Runtime Estimation
Choosing the right APC UPS and knowing its runtime capacity is crucial for ensuring your equipment remains operational during power outages. APC offers a range of UPS models, each with different battery capacities, efficiencies, and supported runtimes.
How Runtime is Calculated
Runtime depends on multiple factors, including the UPS model, battery condition, ambient temperature, and the actual power load connected to the UPS. The general rule is: the higher the load, the shorter the runtime. Each UPS model has a discharge curve, and this calculator provides an estimate based on typical performance benchmarks.
Typical Runtime Performance
Here are typical runtime estimates based on APC UPS models, assuming the UPS is operating at a 50% and 100% load:
| APC Model | Capacity (VA) | Max Wattage | Typical Runtime @ 50% Load | Typical Runtime @ 100% Load |
|---|---|---|---|---|
| BX1500M | 1500 | 865W | 10 minutes | 3 minutes |
| SMC1500 | 1500 | 900W | 15 minutes | 5 minutes |
| SMT1500 | 1500 | 1000W | 17 minutes | 6 minutes |
| SUA2200 | 2200 | 1980W | 24 minutes | 9 minutes |
| SRT3000 | 3000 | 2700W | 30 minutes | 12 minutes |
Practical Tips for Runtime Optimization
- Keep connected load below 80% of UPS capacity for best efficiency.
- Test your runtime regularly using simulated outages.
- Maintain battery health with regular checks and timely replacement.
- Place UPS in a well-ventilated area to avoid overheating.
Why Use a Runtime Calculator?
Manual estimations can be misleading due to battery aging, temperature, and inverter efficiency. This calculator simplifies estimation using real-world performance data, so you can better plan your critical backup needs.
Advanced Use Cases
For environments like server rooms or network closets, precise runtime planning ensures safe shutdown procedures or generator switchover timing. Businesses relying on uninterrupted systems can avoid costly downtime by understanding UPS capacity under various loads.
Frequently Asked Questions
Does the runtime include battery aging?
No. This calculator assumes a new or healthy battery. Runtime decreases with battery age.
How accurate are these estimates?
They are based on APC published specs and real-world testing, providing a close approximation under standard conditions.
Can I add extra batteries to extend runtime?
Yes, many APC Smart-UPS models support external battery packs for extended runtimes.
What if I use only 30% of the rated load?
At lighter loads, runtime increases significantly. You may get 2–3 times the runtime compared to 100% load.
Should I oversize the UPS?
Only slightly. Oversizing by 20–30% is recommended to handle load surges and battery degradation.