A mall in the Southwest was to be renovated and expanded. The facilities had been served by two utility feeders through a seven-bay lineup of automatic source-transfer S&C Metal-Enclosed Switchgear. The two feeders did not have sufficient capacity to carry the additional 4 MW of load. A third was clearly needed. But there were several daunting issues to resolve: How could automatic source transfer be implemented with three sources? How could the load be distributed? No single feeder would have the capacity to handle the entire load. How could SCADA monitoring be implemented?What did they do?
The existing switchgear could not be modified to accommodate the additional load and needed to be replaced. S&C Pad-Mounted Gear with Micro-AT® Source-Transfer Controls was considered. S&C Pad-Mounted Gear with EnergyLine® Automatic Switch Controls and the IntelliTEAM® Automatic Restoration System was also considered.
How did they do it?
The latter approach seemed the most promising and was selected. Four units of S&C Pad-Mounted Gear were furnished, each with an EnergyLine® 5802 Automatic Switch Control. Each control operates two power-operated S&C Mini-Rupter® Switches. Standard IntelliTEAM software prevents the entire load from being transferred to one source in the event of a rare double-contingency outage.
Results
The new gear and controls have provided excellent service continuity for the expanded facilities.