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Vertiv I Liebert ITA2 30kVA I Manual
b) Repeat steps a) to h) in Part 1 to complete the single unit commissioning of the added
UPS. Then completely power off the UPS.
c) Ensure that the connection of power cable and signal cable is reliable.
d) Close the external input switch of the added UPS. After the system power-on, find any
online UPS, and enter the interface shown in Figure 3-7. Set the system parallel No. from 'N'
to 'N+1', then click the 'Sync parallel parameters'.
e) Close the external output switch of the added UPS once again, normally start the inverter
after the rectifier start-up. Then check that the LCD has no alarm, and that the UPS parallel
system works normally.
1. For 1+1 parallel system, when one UPS is faulty and needs to be replaced on line,
the above operation steps are available too. The difference is no need to change
parallel No., just click the 'Sync parallel parameters' for the online UPS.
2. Clicking the 'Sync parallel parameters' to achieve the synchronization of the items
in parallel settings interface, and the parameters will affect the parallel system. The
user should manually set other parameters according to actual needs.
3. When parallel system has output, 'Sync parallel parameters' function can only be
achieved via the UPS with output, otherwise this function is invalid.
4. When adding a single unit in the parallel system, first ensure the parallel cables
connection is correct, then power on the single unit.
3.6
Installation And Commissioning For Dual Bus System
3.6.1
Introduction
The dual bus system consists of two independent UPS systems; each UPS system consists of
one or two parallel-connected single UPSs, or more parallel-connected single UPSs.
The dual bus system has high reliability, which is suitable for the load with many input
terminals. For single UPS input load, you can add a static trigger switch (STS, optional) to
start the standard Load Bus Synchronization (LBS) system.
Place the UPSs side by side, and connect the UPSs as follows:
The dual bus system adopts the LBS system to realize the output synchronization of the two
independent (or parallel) UPS systems. One is the master system, and the other is the slave
system. The operation mode of the dual bus system contains master system and/or slave
system running in Normal mode or Bypass mode. The schematic diagram of the LBS system
built by two UPSs is shown in Figure 3-8.
