UPS Basic Knowledge Summary- Different operating modes of UPS

Time of issue:2023-03-28


Different operating modes of UPS:

Stand-alone system:

Advantages: The system configuration is simple, the hardware purchase cost is low; the UPS system is fully utilized, because the capacity of the UPS is close to the capacity of the system load.

Disadvantage: Reduced availability of the system in the event of a UPS failure. When maintaining the UPS, the system will directly switch to the mains power supply; if the UPS fails, the system has no redundancy; multiple single point failure systems.

Running in tandem:

The method to improve the reliability of UPS - series hot backup: it can be composed of two UPSs with different capacities, the main unit has an important load, and the backup unit has a secondary load or no load; the switch from the main unit to the backup unit is uninterrupted.

Advantages: high reliability; simple connection.

Disadvantages: capacity cannot be increased; overload capacity cannot be increased; UPS cannot be fully utilized.

Running in parallel:

The method to improve the reliability of UPS - direct parallel connection. It is composed of 2 to 4 single-type UPS, each UPS has its own static bypass, which can realize: parallel redundancy; parallel expansion.

Advantages: simple parallel connection; no increase in land occupation; reasonable price; load sharing. It is currently the most used mode of operation.

Common bypass parallel operation:

The method to improve the reliability of UPS - parallel connection of public bypass. It consists of 2 to 6 parallel UPSs of the same capacity, and adopts a large-capacity public static bypass switch cabinet to achieve: parallel redundancy; or parallel expansion.

Advantages: large overload capacity of public bypass; high reliability.

Disadvantages: slightly larger area; more expensive.