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Multiple Module Block Diagram
Planning
Special attention must be taken when planning for parallel system installation. The system power cables (input and output) should
be the same length. Differences in cable length of 20% are permitted for cables up to 60ft, but for longer cables differences must not
exceed 10%.
Another important factor to consider is the total size of the parallel UPS configuration. The output power rating of the UPS should be
specified according to the power demand of the protected loads. Some margin of error should be allowed for potential expansion,
and possible inaccuracy in calculations or measuring the actual load requirements.
The battery should be sized according to the desired backup time. Note that the backup time is longer if the load is less than the
nominal power rating of the parallel UPS system.
Fig 11- Parallel Configuration
