Configuring Your Neutraland Ground Connections 17
7.3 Preferred Grounding Configurationwith Power-Tie Switchgear
Figure 5 Preferred Grounding Configuration, Power-Tie Systems
Multi-Module Systems can be used with Power-Tie switchgear to provid e dual critical load busses.
The Power-Tie switch gear permits transferring c ritical loads from one criti cal bus to the other so
that one UPS system and associated breakers can be de-energized forma intenance.Certain con-
figurationsof 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 tot he Power-Tieswitchgear
neutral. The UPS modules, as usu al, must have their output neutrals solidly connect ed to their
respective SCC neutrals.There should not be a connection between the service entrance neutral
and either the SCC or modul e neutrals.
NOTE
It is essential to run a neutral connection betw een the tie switchgear and
bothSCCsasshownintheillustrationabove.