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.calc-input-group label { display: block; font-weight: 600; margin-bottom: 8px; color: #2c3e50; }
.calc-input-group input, .calc-input-group select { width: 100%; padding: 12px; border: 1px solid #ccc; border-radius: 5px; font-size: 16px; box-sizing: border-box; }
.calc-btn { background-color: #0073aa; color: white; padding: 15px 25px; border: none; border-radius: 5px; font-size: 18px; font-weight: bold; cursor: pointer; width: 100%; transition: background-color 0.3s; }
.calc-btn:hover { background-color: #005177; }
.calc-result { margin-top: 25px; padding: 20px; border-radius: 5px; background-color: #f8f9fa; border-left: 5px solid #0073aa; display: none; }
.calc-result h3 { margin-top: 0; color: #0073aa; font-size: 20px; }
.result-value { font-size: 24px; font-weight: bold; color: #d32f2f; }
.article-section { margin-top: 40px; line-height: 1.6; border-top: 1px solid #eee; padding-top: 30px; }
.article-section h2 { color: #2c3e50; font-size: 24px; }
.article-section p { margin-bottom: 15px; }
.table-data { width: 100%; border-collapse: collapse; margin: 20px 0; }
.table-data td, .table-data th { border: 1px solid #ddd; padding: 10px; text-align: left; }
.table-data th { background-color: #f4f4f4; }
function calculateBackupTime() {
var load = parseFloat(document.getElementById('loadWatts').value);
var capacity = parseFloat(document.getElementById('batteryCapacity').value);
var voltage = parseFloat(document.getElementById('batteryVoltage').value);
var efficiency = parseFloat(document.getElementById('upsEfficiency').value);
var resultArea = document.getElementById('resultArea');
var timeOutput = document.getElementById('timeOutput');
var breakdownOutput = document.getElementById('breakdownOutput');
if (isNaN(load) || isNaN(capacity) || isNaN(efficiency) || load <= 0 || capacity <= 0) {
alert("Please enter valid positive numbers for Load and Capacity.");
return;
}
// Efficiency converted to decimal
var efficiencyDecimal = efficiency / 100;
// Formula: (Ah * V * Eff) / Watts = Hours
var totalHours = (capacity * voltage * efficiencyDecimal) / load;
var displayHours = Math.floor(totalHours);
var displayMinutes = Math.round((totalHours – displayHours) * 60);
resultArea.style.display = "block";
if (totalHours 0) {
timeString += displayHours + " Hour(s) ";
}
if (displayMinutes > 0 || displayHours === 0) {
timeString += displayMinutes + " Minute(s)";
}
timeOutput.innerHTML = timeString;
breakdownOutput.innerHTML = "Based on a " + load + "W load with " + efficiency + "% efficiency.";
}
// Scroll to result for mobile users
resultArea.scrollIntoView({ behavior: 'smooth', block: 'nearest' });
}
UPS Battery Backup Calculator
Total power consumption of all connected devices.
Ampere-hours (found on the battery label).
12V (Single Battery)
24V (2 Batteries in Series)
36V (3 Batteries in Series)
48V (4 Batteries in Series)
Standard UPS efficiency is usually between 70% and 90%.
Estimated Backup Time:
How to Calculate UPS Battery Backup Time
Choosing the right UPS (Uninterruptible Power Supply) and battery configuration is critical for maintaining power during outages. Whether you are backing up a home office, a gaming PC, or critical networking equipment, understanding the relationship between load and battery capacity is essential.
The Mathematical Formula
The standard formula used to calculate backup time for a lead-acid or lithium battery in a UPS system is:
Backup Time (Hours) = (Battery Capacity in Ah × Input Voltage × Efficiency) / Total Load in Watts
Key Variables Explained
- Total Load: This is the sum of the power consumption (Watts) of all devices plugged into the UPS. For example, a standard desktop PC might pull 200W, while a router pulls 15W.
- Battery Capacity (Ah): Measured in Ampere-hours, this represents how much energy the battery can store. Common sizes range from 7Ah for small UPS units to 200Ah for tall tubular batteries.
- Efficiency: No UPS is 100% efficient. Energy is lost as heat during the conversion from DC (Battery) to AC (Home Appliances). Most standard inverters operate at 80% efficiency.
- Battery Voltage: Most home UPS systems use 12V batteries. High-capacity systems may use 24V or 48V configurations.
Typical Load Examples
| Device Type | Average Power (Watts) |
|---|---|
| Wi-Fi Router | 10W – 20W |
| LED Light Bulb | 9W – 15W |
| Laptop Computer | 50W – 90W |
| Desktop PC (Standard) | 150W – 250W |
| Gaming PC (High End) | 400W – 600W |
Tips for Maximizing UPS Life
1. Avoid Overloading: Never exceed the rated VA (Volt-Ampere) capacity of your UPS. Operating at 70-80% capacity is ideal for longevity.
2. Deep Discharge Protection: Try not to drain the battery to 0% frequently. Lead-acid batteries last longer if they are kept above 50% charge when possible.
3. Ventilation: Keep your UPS and battery in a cool, dry place. Heat is the primary enemy of battery lifespan.