Difference: UPS – inverter

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What is the difference between a UPS (uninterruptible power supply) and an inverter?

What both have in common is that they have batteries from which they generate 230 V alternating voltage.

UPS

A UPS (UPS - Uninterruptable Power Supply) is used to provide an uninterrupted power supply to sensitive electronic devices that do not tolerate voltage fluctuations and, even very short, power failures.

During mains operation, a UPS additionally processes the nominal 230 V AC input voltage if necessary. Assuming that only 218 V is available on the input side, the UPS transforms this to the usual 230 V and makes it available on the output side. The voltage regulation is permanent and fluid, and the mains frequency of 50 Hz is also monitored and adjusted. This ensures the availability of the correct electrical parameters for connected consumers at all times.

If the mains alternating voltage on the input side fails, the UPS switches to battery operation within less than 20 milliseconds and generates the required 230 V alternating voltage from the battery direct voltage.
Since the switching process takes place in this very short period of time, the connected devices do not notice the brief power failure and continue to work as usual.

In the domestic environment, these are usually PCs, routers, etc. In the medical sector, life support systems, operating rooms, etc. are supplied via uninterruptible power supplies for a short period of time, namely until they are taken over by the emergency diesel generators.
Other devices, such as perfusors, ventilators, etc. usually have built-in batteries that provide uninterrupted power supply in the event of a power failure.

Inverter

Inverters are used where batteries are charged, for example by photovoltaic systems, or in mobile homes to operate devices that operate on 230 V. So they serve not an uninterruptible power supply in the event of a power failure.

Further information on inverters can be found in a separate one Contribution.