Electrical Contracting News (ECN) September 2016 | Page 35

UPS

UPSs must offer a fast,
flexible response to every
situation that potentially
threatens their critical load.

CUT THROUGH THE STATIC
UPSs are well known as devices that can support critical loads by using stored energy during mains
power blackouts. In reality though, they must also offer protection from electrical noise, spikes and
surges as well as overloads and possibly even failures within themselves. To provide protection from
these various threat calls, amongst other things, static switches respond quickly to the different demands
they are subjected to. In this article, Alan Luscombe at Uninterruptible Power Supplies Ltd explores
the role of static switches and their contribution to UPS protection.

U

ninterruptible power
supplies (UPSs)
are essential to
any enterprise
that depends on
a continuously
available IT resource
for its business

or processing operations – but their full
contribution to IT equipment and data
protection is not always entirely apparent.
Wikipedia, for example, defines a UPS
as ‘an electrical apparatus that provides
emergency (battery) power when the
mains or other input power source fails’;
other sources give similar definitions.

UPS role
Although there’s nothing inaccurate
about this statement, it doesn’t fully
reflect the UPS role. In fact, UPSs filter
out many types of mains disturbances,
including electrical noise and voltage
sags and brownouts, spikes, surges and
supply frequency changes – all of which

can cause loss of data or hardware
damage if allowed through to the IT
equipment. UPSs must also cater for
failures within themselves, although the
effect of these can be minimised with
redundant configurations.
While maintaining a fully charged battery
at all times is clearly critical to the UPS

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10/08/2016 16:28