It is important that you select the right UPS system in order to maintain a constant power source and protect sensitive equipment. There are many types, but two of the more commonly used types are Double-Conversion UPS and line-interactive UPS. Each type has advantages and disadvantages and the right application depends on the ideal balance between performance and cost.
What Does Line Interactive Mean on a UPS?
A Line Interactive UPS maintains voltage regulation until it must switch to battery power. If the variation in power is within an acceptable range, this UPS will use an automatic voltage regulator (AVR) to regulate, either boosting or lowering voltage as needed. It provides good performance for small to medium-sized businesses, home office set-ups, and retail applications with occasional fluctuations, where full-time power conditioning is not a must.
The strength of this UPS is the value for cost. It offers a good level of performance and provides good value for certain non-critical applications.
What Is a Double Conversion UPS?
An Online Double Conversion UPS represents the highest level of power protection. It constantly converts incoming AC power to DC and then back to AC. Doing this ensures that your equipment is always operating on clean, stable power free from power disturbances such as surges, sags, or frequency variations.
With the constant conversion, there is no transfer time during power outages, making it a great fit for data centers, medical equipment, or other critical infrastructure that must run continuously without interruptions (even minor ones).
What is the Difference Between a Line Interactive and a Double Conversion UPS?
The main difference is in how each responds to power disturbances:
A Line Interactive UPS can correct minor disturbances without switching to battery power. The battery only engages when power is lost, or if the voltage drop is significant enough, there will be a time until the battery can enable operational power.
A Double Conversion UPS constantly supplies power via its internal inverter, providing seamless power without delays and generally better power quality.
Here’s a quick comparison:
| Feature | Line-Interactive UPS | Double Conversion UPS |
| Transfer Time | A few milliseconds | Excellent |
| Power Conditioning | Moderate | Excellent |
| Cost | Lower | Higher |
Choosing the Correct UPS System
When powering critical servers, hospital equipment, or industrial control systems, a Double-Conversion UPS is likely your most ideal option due to its superior power conditioning and reliability. But if powering desktop PCs, networking equipment, or point-of-sale systems, then a Line-Interactive UPS may be entirely sufficient and a better value.
In conclusion, the decision about which one of the UPS types to use will come down to power protection requirements and budget. Keep in mind that with a Line Interactive UPS, you can consider more relaxed requirements and also provide a reasonably good and economical UPS solution, while a Double Conversion UPS provides total protection for those scenarios where continuity is paramount.