Reference Guide

Choosing a UPS or SBS
Selecting the appropriate Uninterruptible Power Supply (UPS) and Standby Power Supply (SBS) components ensures that only
clean power is delivered to Storage Center and that the system is protected from power surges and outages.
There are different levels of UPS/SBS protection available:
● Online UPS
● Line-Interactive SBS
● Off-Line SBS
NOTE: Each of these UPS/SBS types typically provides 5–15 minutes of battery backup time when loaded to full output
capacity. Longer backup times may be achieved by overrating the UPS/SBS size.
Online UPS
Online UPS provides the best type of UPS/SBS protection available. It protects Storage Center from irregular voltage from an
incoming utility, provides sufficient backup battery capabilities, and is enhanced with an electronic firewall between the incoming
utility power and Storage Center.
technical support recommends using an online UPS for Storage Center protection for the following reasons:
● Online UPS provides an electronic layer of protection from variations in power quality through the use of circuit tiers. The
incoming AC utility voltage passes through a surge protection process where it is converted to DC and filtered by capacitors.
This tier removes line noise, high voltage transients, harmonic distortion, and any other 50/60 Hertz (Hz) related issues.
● Online UPS provides a voltage regulator stage where the DC is filtered through a second set of storage capacitors giving
UPS the ability to sustain constant output during a low voltage condition or brown-out.
● Online UPS passes the regulated DC voltage to an inverter stage where it creates true sine wave output power.
● The Online UPS capacitors act as an energy storage reservoir allowing the UPS to work through momentary power
interruptions.
● The Online UPS battery performs a seamless transition by replacing the energy source during a power outage.
Line-Interactive SBS
Line-interactive SBS provides a mid-level of UPS/SBS protection. Much like an off-line SBS, it protects Storage Center from
power surges and provides backup battery protection. Unlike off-line SBS, it has the added feature of providing a minimal
incoming voltage regulating transformer that protects Storage Center from powering down during extended periods of low
voltage power from the incoming utility or brown-out conditions.
NOTE:
If you choose a line-interactive SBS, select one that accepts extended battery packs and has an inverter with true
sine wave output. For more information about sine wave output, see Off-Line SBS.
Off-Line SBS
Off-line SBS provides the most basic type of UPS/SBS protection available. It protects Storage Center from power surges and
provides rudimentary backup battery protection.
Off-line SBS connects Storage Center directly to incoming utility power, similar to a common surge-protection power strip. If
the incoming utility voltage falls below a predetermined level, the off-line SBS turns on its internal DC-AC inverter circuitry
powered from an internal storage battery. It then mechanically switches the connected components to its DC-AC inverter with
a relatively high switch-over rate.
technical support does not recommend relying on an off-line SBS for Storage Center protection for the following reasons:
● Because off-line SBSs are designed to operate from a standard 120 volt, 60 Hz sine wave utility source, it may only provide
sine wave output to Storage Center when operating normally from the utility line. If they switch to their internal DC-AC
inverter, they may not deliver pure sine waves. This action may cause Storage Center to appear as if it is operating normally,
but may actually be damaged with long-term use.
NOTE: If you choose an off-line SBS, select one that has an inverter with true sine wave output.
● Most off-line SBS units are not capable of accepting additional battery packs for extended battery operation. These units are
designed to prevent overheating and only operate as long as the internal battery capacity allows.
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