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Modular UPSs
In recent years the need for continuity of power supply and ease of maintenance and management has led to the emergence of UPS
with modular architecture. Modular UPS are made up of several transformer-less Online Double Conversion
UPS (modules) working in parallel within a single system. The total power of the UPS is the sum of the power
of the individual modules. In modular systems it is easy to achieve redundancy or increase the power by
simply adding one or more modules, without having to connect several UPS in parallel. Furthermore, in
modular UPSs, any faults in the power circuits remain confined within the individual module, which is
automatically excluded. The lower the power of the individual modules (granularity), the less power is lost in
the event of a fault and the easier it is to replace a faulty module. Typically, the granularity brings high
advantage and flexibility with Power Modules of 25 kW or less. Legrand proposes the Keor MOD UPS as the
last frontier of Modular Granular System, fully redundant with super compact power modules of 25 kW each,
for maximum power of 600 kW.
Salable Systems
At High power levels (from 500 kW up to some MegaWatts), the Redundancy and granularity can be obtained connecting in parallel
Modular UPS or using Modular System with big size Power Units in parallel, these systems are also called Scalable. In Scalable
systems the Power Units are Conventional UPSs in parallel and connected to a dedicated distribution and control units which
manage them as Power Modules, allowing redundancy, hot service and hot scalability.
Keor XPE System is the Legrand proposal for Scalable UPS, with Power Units of 250 and 300 kW can reach up to 2.1 MW Power, with
possibility to have redundancy, hot serviceability and hot scalability.
Scalable / Modular Construction
A further step in high power and serviceability is to use Scalable UPS with Power Units designed with internal modular construction.
This type of system combine together the Flexibility in high power of Scalable UPS with the resilience and
serviceability of the Modular granular UPS. Connecting in parallel more of these Scalable Modular System
gives the possibility to reach power level over the 20 MW. Legrand offer the UPSaver a top level Scalable
Modular UPS System. UPSaver with Power Units of 333 kW (based on 6 sub functional modules), can reach
up to 2.67 MW with a single system and up to 21 MW in parallel system, with maximum availability at high
power level.
Synchronized UPS Systems
In modern Data Center, with high redundant architecture, it is typical to have dual power lines distribution and to give two independent
power sources to active IT load with redundant power supply.
In this case each line is protected by one UPS system, often in N+1 redundancy, but, whenever the two lines are separated and
independent it could be needed to keep them synchronized. In particular it is important to have a perfect commutation from one
line to the other line in case of STS (Static Transfer Switch) systems. (For instance for loads with single power supply stage or in
configurations were various UPS lines are distributed through STS to various dual lines part of the Data Center.)
Thanks to cutting edge logic controls, Legrand UPS for Data Centers are capable to run in Synchro for dual power lines distributions.
CONTINUITY
Legrand UPS and business continuity (continued)
