FAQ (Uninterruptible Power Supply – UPS)

FAQ Uninterruptible Power Supply UPS

An Uninterruptible Power Supply commonly referred to as UPS is an electronic device that provides short term emergency power supply when the regular input power fails.  Uninterruptible power supplies offer power protection solutions for just enough time for an alternative standby power source to begin or for information to be saved, protected and shut down safely. Common power problems causing power disruption are due to utility failure and abnormal line voltage, whether continuous overvoltage or voltage spike or input voltage reduction.

 Uninterruptible Power Supply Uses

UPS are most commonly used to protect PC’s, servers, data centers and any equipment where power disruption could cause injury, data loss and business damage.  Most UPS devices provide an instant backup power supply as well as surge protection with units ranging in size, smallest for desktop computers and large ones for entire rooms or buildings. 

 UPS advantages

While only working as a short term solution, the UPS is advantageous over emergency power system and standby generators in that it offers true power continuity by providing instantaneous protection thus saving data that would otherwise get lost using the latter solutions.

 Uninterruptible Power Supply Types

To maintain continuous power supplies energy storage backup battery, an AC-DC charger and a DC-AC inverter are needed.  The three main types of UPS use these three things but in different ways.

 Standby UPS (SPS)

The Standby UPS or offline as it is also referred to, offers surge protection and battery backup. It works by switching the load when the primary AC source fails to the battery-powered inverter.  This switch takes place once the device determines the incoming voltage has fallen below a minimum level and therefore does not really provide complete uninterrupted power supply. Since most devices’ internal PSU have hold up time longer than the time taken for the switch over, this generally does not pose a problem.  With the highest efficiency and reliability as it only works when the power supply fails and being the cheapest UPS power supply, the Standby is perfect for personal computers and other small devices.

 Line-Interactive UPS

A line-interactive UPS is similar to standby but keeps the inverter in line redirecting the battery’s DC current path from its regular charger when the power source fails.  The line-interactive UPS deals with overvoltage surges and under voltage brownouts by automatically selecting different power taps on the autotransformer and thus conserving the limited reserve battery power. This special transformer is also referred to as a buck-boost transformer because of the way it works. By “bucking” an overvoltage and “boosting” an under voltage. The line server’s main applications are small servers and networks.

 Online / double-conversion

The online UPS is mainly used for devices which are very sensitive to power fluctuations. The online or double conversion works by constantly supplying some power supply even under normal conditions ensuring there is true continuous powers supply at all times. It is called a double conversion for this reason. The online UPS is most expensive due to it having a much greater current AC-to-DC battery-charger/rectifier which must be able to run continuously. The double energy processing results in reduced efficiency but for sensitive electronic equipment the online’s advantage of providing an electrical firewall is necessary.

Other UPS designs include the hybrid topology and Ferro-resonant units, DC power and Rotary.

Hybrid topology works like the off-line/standby UPS as long as the power is within a certain range.  As soon as power fluctuations over a predefined range occur the UPS switches to working as an online/double conversion system.  In this way the system is able to maintain high efficiency when in the standby mode yet provide the necessary power when required. For this reason the hybrid is also referred to as a double conversion on demand UPS system.

The Ferro resonant unit is similar to the standby but with an additional transformer which filters the output. This Ferro resonant transformer has enough power to cover the time taken for the transfer from power line to battery power ensuring continuous supply. This type of UPS is less popular today than it was but is still used in industrial settings, for gas, oil, and chemical and heavy industry markets.

 Powering DC equipment requires an online UPS without an output inverter. By matching the voltage of the UPS’s battery to the voltage required for the machine, one can eliminate the need for the equipments power supply, which increases its efficiency and speed. This type of UPS can theoretically be very useful for telecommunications and data centers but extreme care has to be taken when playing around with voltage levels.

Larger power units sometimes use dynamic uninterruptable power supplies with energy stored in flywheels and Eddy current regulations maintaining the power when the main power fails.

The Rotary is one of the oldest UPS designs and is mainly used for large equipment requiring a minimum of 10,000 watts backup power, in order to benefit most from its system and due to its high cost of use.  It supplies a power supply for a very brief amount of time, just enough for the engine to start running and stabilize its output. Diesel Rotary uninterruptable power supply is sometimes formed by combining DUPS with a diesel generator.

Large businesses often opt to use multiple smaller UPS systems integrated to work together and supply power when necessary as opposed to one very large UPS which can be less reliable and even cause damage or disrupt systems.

 Choosing Your UPS

In order to determine what type and how powerful a UPS you require, add together the wattage of the various devices you want your battery pack to protect and then ensure the UPS you are getting can protect it all. You want to be sure the UPS offers continuous power supply as well as surge protection to prevent any damage until your device is safely turned off or gets a suitable alternative power supply.

Although UPS sources are not suitable for all applications, where used they provide an immediate short term power supply that prevents data loss and damages and in some cases even fatalities.

 Pioneer System is the leading company in Pakistan for UPS products. The company’s UPS systems are known for their outstanding quality and they provide uninterruptible power supply to defense industries, IT centers, hospitals and companies all over the world. Pioneer System offers a wide range of uninterruptible power supply systems including online double conversion UPS and three phase UPS. Pioneer System’s efficient uninterrupted power supply solutions will guarantee your peace of mind!