Understanding UPS design types can make all the difference to ensure that critical applications such as industrial, oil/gas, IT/IIoT and security systems are protected against power disturbances and outages.

An uninterruptible power supply (UPS), also known as battery backup, provides different levels of protection against power problems, depending on the UPS type: online, standby (offline) or line-interactive. 

Online vs. Standby (Offline) and Line-interactive UPSs

Aren’t all UPSs the same? No. A true double-conversion online UPS is the optimal solution for critical applications. Don’t be confused – “online” doesn’t mean that the UPS is plugged in and turned “on.” Some UPS manufacturers mislead consumers about their UPS design’s true capabilities. 

Online UPS 

The double-conversion online UPS provides the best level of power protection for critical applications.

Why? In contrast to the other two designs, an online UPS continually regenerates new, clean AC power through its continuous duty inverter and seamlessly operates on AC or DC (battery) power.

It also has several layers of protective circuits that further safeguard connected equipment and ensure it is always receiving 100% conditioned and regulated AC power.

Additionally, an online UPS can provide long periods of battery runtime by adding extra battery packs. 

Standby and Line-interactive

Standby and line-interactive UPSs turn on the inverter when the power fails and can only provide short periods of battery runtime (by design). This leads to an interruption (transfer time) when the inverter power takes over. Also, during normal operation, they leave equipment connected directly to the utility with very limited protection from common power disturbances. This may be acceptable for non-critical devices, but it has a risk factor. If an application can’t afford risks, the right solution is an online UPS.

UPS Batteries and Service Costs

A little-known fact is that the UPS type — online, standby or line-interactive — affects battery life. A lead-acid (VRLA) UPS battery is rated at 3 to 5 years of life. Due to their lower-cost design, standby and line-interactive UPS models can switch to the battery excessively if installed in locations where utility voltage or frequency regulation is poor.

Every time the battery is cycled, the battery life is reduced. So, in reality, users can face costly battery replacements every 1 to 2 years, especially in industrial environments where cold and heat further reduce battery life.

This is not the case with online UPS models as they only draw power from the batteries when the utility voltage is extremely low or lost completely. In fact, the new generation of online industrial UPS (like Falcon’s SSG Industrial UPS) have 12-year rated batteries when operating at an ambient temperature of 25°C (77°F) and can last 4 years when operating at 50°C (122°F)! This wide operating temperature range eliminates costly and frequent battery replacements.

New Generation of Online Industrial UPS models

Online industrial UPS systems, such as Falcon’s SSG and SSG-RP families, are available for industrial settings where wide temperature and other demands are encountered. Online, industrial UPS models are specifically designed to meet the rigors of these environments. For example, Falcon’s SSG Industrial UPS has a wide operating temperature range of -20°C to 55°C (-4°F to 131°F). 

Bottom Line

When considering a UPS solution, be aware of the UPS type and corresponding level of protection. Ask the question: Can I take a risk with my applications and devices? If not, then an online UPS with long-life batteries is the right solution.

For an in-depth overview, read the UPS Tutorial