UPS the same protection levels as available to their larger data centre counterparts . To understand how such marriages can be made , we can start by looking at the UPS requirements and constraints that characterise server rooms ; some are the same as for data centres , but others differ . With this profile in mind , we can then review one solution that is currently available .
Scaling for server rooms
An essential and primary consideration should be the UPS ’ s topology . Server rooms , as data centres , should use dualconversion , online solutions , as these alone secure full protection against all possible mains-borne disturbances as well as complete power blackouts . Dual-conversion UPSs are so-called because of their two conversion stages ; a rectifier for AC / DC , and an inverter for DC / AC . In online configurations , incoming utility power , when present , always passes through these two stages before reaching the load , which is connected to the inverter output . The UPS components continuously shield the load from mains-borne noise and transient voltage excursions , as well as providing a constantly well regulated supply .
‘ As most modern data centres contribute critically to their owners ’ business continuity , it ’ s unsurprising that they rely on UPSs to assure clean , uninterrupted power at all times .’
If the mains supply does fail , the inverter continues to support the load without interruption , by drawing power from the UPS battery . Flexibility in battery configuration is therefore desirable , to set up a battery autonomy to support a load of known size for a given time , or to provide a grace period either for a generator to start up , or for the load to be shut down safely .
Offline systems , by contrast , connect the raw mains directly to the load during normal operation , exposing it to damage from any incoming voltage aberrations , as well as subjecting it to a short duration but finite supply break during any transfer to the inverter output .
As the UPS fulfils its role in providing protected power , its own availability is essential in server rooms , just as in larger data centre applications . Redundancy should be designed in wherever possible , as this significantly elevates availability . If single points of failure are eliminated , the UPS system can become resilient to component or even unit failures , providing maintenance and support partners , as uptime depends on these factors as much as on the equipment installed .
But what about smaller ICT users like server rooms or communications centres ? With business activity and installation size less than a data centre ’ s , their budget , manpower and space resources are correspondingly reduced . However , their need for protected power remains just as critical . Fewer people may be affected if a server room rather than a large data centre is compromised by power problems , but for those that are , the consequences may be just as severe .
Fortunately , though , answers are available . It is possible to purchase UPS solutions , in terms of both hardware and support , that are scaled to mid-sized server room requirements while offering
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