UPS system introduction

There are essentially three different topologies of Uninterruptible Power Supply systems available on the market today:

Stand-by, Line Interactive and True On-line Double Conversion UPS.

The question is: which type do you need?

Standby UPS systems:

Also known as offline, are an adequate choice for small, less critical applications such as isolated PC’s and peripherals. Almost all standby UPS’s will switch to battery fast enough to give backup power through most outages, although they do only offer very limited protection to spikes and sags in the mains power.

Line Interactive:

Technology gives highly effective power conditioning along with its battery backup. They are a great option for locations where power outages are rare, but there are frequent power fluctuations.
Line interactive UPS’s have voltage boost circuits which will boost and clip high and low voltages to give a constant output voltage.
Surges and spikes are also eliminated more efficiently than with an offline UPS system.

True Online Double Conversion:

An Online UPS provides the highest levels of power protection, conditioning and UPS backup available. There is no switching from mains to battery so there are no switchover time issues: this is often important for high speed data transmissions and switching equipment.

The power from these Online UPS is far superior to that of the other types of UPS as it completely regenerates the sine wave, instead of to simply recondition the raw mains supply. On-line systems also provide frequency regulation, which is essential for use with backup generator systems. Some On-line UPS systems can also be used as Frequency Converters for 60Hz requirements.