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 35 35-36 UPS – UPSL.indd 35 10/08/2016 16:28