What Is Uninterrupted Power Supply

What Is Uninterrupted Power Supply

An uninterrupted power supply is a valuable piece of equipment that enables electrical machines (usually computers or telecommunication apparatus) to continue to run for a short period of time in case of a power failure.  Different sizes are available, ranging from an uninterrupted power supply for a single machine to entire data centres.  Some even power entire cities to ensure vital services can continue to run for a period of time during a power cut, giving technicians some extra time to try and resolve the underlying issue.

Uninterrupted Power Supply Technologies

Generally, uninterrupted power supplies are on-line, line-interactive or standby. 

  • The standby function offers only the most basic features, meaning it will give protection against surges (when there is a sudden increase in the main voltage) and battery backup.  These are the uninterrupted power supplies most frequently used to provide additional security for personal computers.
  • The line-interactive function is a bit more advanced than the standby function.  It will contain a multi tap variable voltage autotransformer of which the magnetic field and the output voltage can be increased or decreased. 
  • The online function is mainly used in places where equipment is very sensitive to power fluctuations and where electrical isolation is needed.   It is able to provide a kind of firewall between the incoming power and the sensitive equipment that it is designed to protect. 

Usage of an Uninterrupted Power Supply

Uninterrupted power supplies are usually used in:

  • Outdoor environments – you will need to make sure that the machine is weather resistant, including temperature fluctuations, rain and wind. 
    • N+1 – this provides almost the ultimate protection.  Theoretically (and this has actually happened), the thing that causes the initial power failure is actually the uninterrupted power supply, meaning that not only will you lose your power, but also that the uninterrupted power supply will not work.  The N+1 designs combat this, meaning that if it is the module that is causing the power supply, they will provide you with a sort of second backup.
  • Internal systems – these are uninterrupted power supplies that are placed within the machine that they are protecting, for example a personal computer.  Naturally, internal systems can only provide uninterrupted power supply for a single machine.
  • Multiple redundancy – these types of uninterrupted power supplies tap into additional power supplies.  For example, if you have certain machines on one circuit and this circuit fails, the uninterrupted power supply will tap into a different circuit.  This does mean that you need to be sure that the other circuits have sufficient power to carry an additional circuit when necessary.

So, uninterrupted power supplies can be used in a variety of different ways for a variety of different problems.  In general though, they basically provide you with a short space of extra time between a power failure and your machines actually turning off.  This extra time can often be vital to save work or ensure performance is maintained.  The type of uninterrupted power supply that best suits your needs depends on the number of machines you want to protect.