7.3Preferred Grounding Configuration with Power-Tie Switchgear

Figure 5 Preferred Grounding Configuration, Power-Tie Systems

Multi-Module Systems can be used with Power-Tie switchgear to provide dual critical load busses. The Power-Tie switchgear permits transferring critical loads from one critical bus to the other so that one UPS system and associated breakers can be de-energized for maintenance. Certain con- figurations of Power-Tie equipment also permit the operator to continuously parallel the output of both UPS systems.

In tied systems, each SCC must have its neutral solidly connected to the Power-Tie switchgear neutral. The UPS modules, as usual, must have their output neutrals solidly connected to their respective SCC neutrals. There should not be a connection between the service entrance neutral and either the SCC or module neutrals.

NOTE

It is essential to run a neutral connection between the tie switchgear and both SCCs as shown in the illustration above.

Configuring Your Neutral and Ground Connections

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Liebert 600TTM installation manual Preferred Grounding Configuration with Power-Tie Switchgear