The difference between UPS and Power Inverters

125-X-125-B_2Fluctuations in electrical power can result in extreme damages to devices. Thus there is a crying need for a constant and ideally never ending power supply to protect the internal circuitry. Due to several technical and ambient reasons, power supplies are cut off at and for irregular period of intervals. It is then when one needs a battery based power supply which could support the device for a significant amount of time.  Two widely known solutions to battery based power back-up are UPS and inverter. To the end customer, UPS is preferable for computers and its associated peripherals while inverters are used for backing up house appliances like tube-light, fans, coolers, televisions etc. This article deals with the technical and various commercial difference between UPS and Inverter – the two power storage technologies that are used in daily life today.

1. Decoding Names: UPS, standing for Uninterruptable Power Supply, is an electric circuit (device) which instantly backs up power supply for a gadget. The gadgets continue to work on smoothly and there is no damage to it. On the other hand, inverter is circuitry which converts AC to DC and stores in the battery. When power supply goes off, that DC power is converted back to AC and is transmitted to the respective electronic gadget.

2. Working principles: Inverter converts DC power (stored in its battery) to fulfill respective requirements of the devices. It uses relays and sensors to detect when to use DC power, otherwise it charges the battery for DC power. UPS does the similar task of power supply and is quite similar to inverter’s working in order to supply power. However, UPS monitors the input voltage level and processes it in terms of voltage regulations.

3. Changeover time: This is the total time that a battery back-up system takes up to supply power supply after electricity goes off. UPS takes around 10 to 15 milliseconds while an inverter takes up to 500 microseconds.  Though delays in both are nominal and as minimal as they can be, inverter is far better in terms of sensitive power operating gadgets.

4. Input power requirements: Comparatively, inverter has a wider range of input power as compared to UPS. Inverter takes up around 170-270V of AC while UPS works at 240-270V AC.

5. Types: An inverter can be divided into three types: (a) Square Wave, (b) Quasi Wave, (c) Sine Wave inverters. As the name suggests, these types are on the basis of the type of the wave generated.

UPS are of three types, basically: (a) Offline UPS, (b) Online UPS and (c) Line-interactive UPS.

6. Voltage Fluctuations: While voltage fluctuations in input supply can be adjusted by the gadget, the output voltages are desired to be as smooth as possible.  In smoothening the voltage outputs, UPS are considered better as compared to inverters.

7. Circuitry Sophistication: UPS circuitry is far more sophisticated than that of inverter’s. It is due to high quality output expectations along with high reducing the delay in the circuit.

8. Pricing: A highly sophisticated circuit along with swift working makes a UPS more expensive than an inverter.

9. Drawbacks: Inverter’s major drawbacks include more fluctuations in power output, higher delay, and a less quality circuitry. UPS, on the other hand, is more expensive. This restricts its widespread usage for gadgets.

Inverters are preferred more for general electric gadgets whose working doesn’t get affected by extended delays in power supply. UPS are used for gadgets such as computer, servers, workstations which perform critical task and cannot tolerate delays in power supply.

Interestingly, new inverter types such as pure sine wave have reduced fluctuations and delays in output voltages. Since, they are already economic power back up solutions; UPS’ are losing more and more market share, being redundant by the day.