Online UPS vs. Offline UPS: Battle of the Equals

A UPS is a device which offers power backup when there is an outage or voltage breakdown. The UPS, unlike a standby generator, gives immediate protection from interference in the power supply. The backup given by the UPS is relatively shorter than a generator; however, it is enough to start a power backup generator or turn off the device. The basic function of a UPS is safeguarding devices like PCs, data centers, telecommunication devices and other kinds of digital devices.

Usually, UPS systems are classified into 3 types: line interactive, offline and online. In an offline system, the load is basically given for by the input power and the backup is just called upon while the power supply breakdown. An online UPS changes the AC input into the DC for charging the rechargeable battery and then changing the DC back to AC for powering the appliances. This process is known as Double Conversion method. A line interactive UPS utilises an inverter for supplying current while the power supply is lost by redirecting current from the daily charging mode of the inverter.

The offline UPS attaches the devices straight to a power supply. It just gives key features like surge protection and battery backup. Whenever there is a difference in the input supply, the system inside a space of 20-30 milliseconds switches on the circuitry that changes the DC available in the battery into AC and delivers it to the equipment. The time taken for switching over from the input supply to the backup supply relies upon the time taken by the circuitry for finding the lost voltage. This kind of UPS can just be utilised for devices like PCs which need very little power and can manage fluctuations in the supply.

The online UPS is considered perfect for devices which are sophisticated in terms of power fluctuations or for ambience in which power isolation is important. Nowadays, in many nations, power anomalies like sag in utility power, outages etc. are a common incident. The key components of an online UPS are same as that of the offline system. This kind of UPS also has two supplies and transfer switch which chooses between the power supplies. The distinction is that the main supply of the UPS is the UPS battery and the secondary is the mains.

Every system has its own benefits and shortcomings. The benefit of the offline UPS is the initial cost is low, the efficiency at which the system functions is really high, and it is noiseless during the performance. The benefit of the online UPS is that not just does it give constant power conditioning there is also no break while the mains fail and it has a big tolerance range of input voltage. Nevertheless, this kind of UPS is costlier than the other UPS systems. But when comparing both the offline and online UPS, the online UPS clearly wins barring the price difference.