An uninterruptible power supply (UPS) is useful for protecting computer, household, or industrial devices from power outages. In-line, on-line, or off-line, it takes over in the event of a power outage, allowing users to save their data or properly shut down their devices.
Off-line UPS systems have several features to be aware of:
- they convert the direct current supplied by their battery into a crude alternating current when the voltage drops below a defined threshold;
- a micro-interruption of about 6 ms occurs during the switch-over;
- they are suitable for devices with a large capacitor like desktop PCs that are insensitive to the transition micro-interruption;
- the most powerful can reach 1 kVA.
In-line UPS systems are an alternative to off-line models:
- they are equipped with a voltage regulator;
- the micro-interruption is reduced to 2 ms during the switch-over;
- the lifetime of the battery is improved due to voltage regulation;
- they are suitable for NAS servers, SME, and micro-enterprise computer servers, generators, and home cinema systems;
- their power varies from 0.5 kVA to 5 kVA.
On-line models have some notable characteristics:
- they are equipped with a battery that continuously provides alternating current;
- the output voltage remains stable despite power outages or voltage drops at the input;
- they are recommended for sensitive devices like medical equipment or large enterprise computer servers;
- their power exceeds 5 kVA.
Thus, the UPS should be chosen based on the sensitivity of the electronic devices. Its power should be at least 1.6 times the total power of all connected devices. Finally, some UPS systems can control the shutdown of connected devices, even in the absence of the user.
'/%3E%3C/svg%3E){kind=small}