Figure 4 – Liebert 600T User Manual

Page 22

16 Configuring Your Ground and Neutral Connections

7.4

Preferred Grounding Configuration, 480 or 600 VAC Input and Output, with
Power-Tie™ Switchgear

Figure 4

Preferred Grounding Configuration, Power-Tie™ Systems

Single Module Systems can be used with Power-Tie switchgear to provide dual critical load bus-

ses. The Power-Tie switchgear permits transferring critical loads from one critical bus to the

other so that one UPS module and associated breakers can be de-energized for maintenance. Cer-

tain configurations of Power-Tie equipment also permit the operator to continuously parallel the

output of the UPS modules.
In tied systems, each UPS module must have its neutral solidly connected to its own building ser-

vice neutral and to the Power-Tie switchgear neutral. See Figure 6 above.

NOTE
It is essential to run a neutral connection between the tie switchgear and

both UPS modules as shown in the illustration above.

GROUNDING
ELECTRODE
PER NEC 250-24