In-Depth: Uninterruptible Power Supplies

Which UPS system is right for you?

WhichUPS_ThumbnailAll Minuteman UPSs provide full protection from power problems such as blackouts, brownouts, sags, surges and spikes. There are three different types of uninterruptible power supplies that vary in terms of how protection is delivered to attached equipment. The three types are standby, line interactive, and online.

Please keep reading to find the perfect Minuteman solution for your power protection needs.

There are cost differences between these types of UPSs, as well as how protection is implemented. For less mission critical equipment, a standby UPS is generally a good choice. mm_ups_family_2014_medFor more important equipment, a line interactive UPS is a better choice. For the most mission critical equipment, an online UPS is the best choice.

These three different technologies accomplish the same result – complete power protection. Which technology to use is usually driven by budget and type of equipment to be protected.

Standby – Battery or Utility Power

A stand-by UPS is the most basic, lowest priced type of battery backup protection available. During any type of power fluctuation, a standby UPS switches to battery mode to provide clean power to attached devices. Standby UPSs do provide total protection from any type of power problem and are a good choice where there are budget constraints.


With models ranging from 400VA to 750VA, Minuteman’s EnSpire Series provides a low-cost, high performance solution for protecting small load computers, network equipment, and security devices from damaging power problems.

Line Interactive – Battery, AVR, Utility Power

Line interactive UPSs also provide complete protection, but manage incoming power differently than a stand-by UPS. The most common power problems are small variations in incoming AC voltage, such as brownouts or sags, as well as over-voltages, such as surges and spikes. This type of UPS employs an automatic voltage regulator that corrects these anomalies without accessing battery power, thus putting less strain on the battery and extending its life.


Minuteman’s line interactive UPS units include three different product lines, the Entrust LCD, the PRO-RT and the EnterprisePlus LCD Series. The Entrust LCD Series is available in 550 to 1500VA and the PRO-RT comes in 1000VA and 1500 VA, making them a good fit for network devices, security and telephone systems. The EnterprisePlus LCD Series is one of our most versatile units with true sine wave output, and with models ranging from 750VA up to 3kVA, these rack/tower units are suitable for a wide range of applications.


Online – Double Conversion

A true online UPS completely re-generates the incoming AC power to provide the best type of power protection available. This is accomplished by an internal inverter converting incoming power from AC to DC, and at the output, the DC signal is then converted back to AC. Through this double conversion process, the UPS creates an “electrical firewall” to fully isolate attached equipment from any type of power problem.


Minuteman’s online Endeavor units come in a variety of configurations and models ranging from 1kVA up to 10kVA, all with extended runtime capabilities for large applications, including server and network devices, industrial equipment, and more.

To find the product that suits your power needs, please visit