Online UPS (Uninterrupted power supply) is modern power equipment mostly used to ensure reliable power supply to the sensitive machines. It does not only ensure uninterrupted power but also provide many other benefits like protecting from the over or under voltage, voltage serge and harmonics. Normally, online ups is available from 3 kVA to onwards up to 500 kVA or more. Reliability, efficiency and service availability are major concerns for buying online ups. Some lower kVA ups can be found in suppliers ready stock but most of them has to be imported.