GE Industrial Solutions LP11 924 Series 6 & 10 kVA - Manual (Page 26)

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OPM_LPU_11U_6K0_10K_1US_V010.Doc 25 User manual LP11 924 6 & 10 kVA UPS 1.0
4.5.6 – OPERATING 2 / 3 / 4 PARALLEL UNITS – ADDITIONAL INFO
You may skip this paragraph and proceed with chapter 5 if your UPS will operate as a stand-alone unit.
The RPA option (Redundant Parallel Architecture) allows you to create a redundant UPS system in which 2, 3 or 4 UPS
units operate in parallel.
All additional information required for parallel systems is gathered here, in three sections:
- installation (4.5.6.1)
- start-up (4.5.6.2)
- use / maintenance (4.5.6.3)
4.5.6.1 - NOTES CONCERNING INSTALLATION OF A PARALLEL SYSTEM
1. All inputs of the UPSs must be supplied from the same phase. This is to enable bypass operation of the parallel system.
All inputs must be individually protected by fuses in the installation. The values of these fuses should correspond to
the values mentioned in section 4.5 table 1.
2. All outputs must be connected together, supplying the load. It is advised to install switches (S 1-2, fig. 17) in the output
wiring, in order to be able to isolate a unit from the remaining system for service and maintenance purposes. It is
advised to make a Neutral-to-Ground bounding in the output junction.
3. The diameter of input and output cables must be according to the table in the installation drawings (see appendix).
Cables with different diameters can cause tripping fuses in the UPS and/or the installation.
4. The length of all input cables from the input junction (Li, fig. 17) to the UPS inputs should be made as equal as possible
(20% tolerance is allowed). The same applies to the cables from the outputs to the output junction (Lo, fig. 17). The
minimum length of the input as well as the output cables is 3 meters / 10 feet.
Figure 17. Installation of parallel operating UPSs