American Power Conversion 250 A manual How the InfraStruXure Power Generation, System Operates

RestoredUtility

Load

Powered

by Generator

How the InfraStruXure Power Generation

System Operates

Operation of the ATS during a utility failure when automatic operation is enabled

Your data center equipment is typically powered by the utility [Source 1] (), while the generator [Source 2] remains off. When the level of incoming utility power falls below a specified threshold (), the ATS signals the generator to start (). After the generator starts and attains the necessary power to support the load, the ATS performs an open transfer to the generator ().

	Load	
	Powered by
	Utility.	
	Generator
Generator Stopped
	is Off
		Utility Failure



Generator	
Cool-Down	Generator
	Start
	Sequence
 Retransfer to	Generator Started
Utility
(Open or Closed)
	Open Transfer 
	to Generator

The generator then continues to support your data center

equipment () until an

acceptable flow of utility power is restored (). The

utility power must remain

stable for a specified length of time (Line Stable setting) and the generator must run for at least the duration of its minimum run-time (Min on Gen setting) before the load will be retransferred to the utility (). The retransfer to the utility can be either open or closed. Following retransfer, the generator cools down () and eventually stops.

For more information.

See page 33 for a description of how the ATS determines the line quality is bad. See page 7 for a detailed description of the generator start sequence.

See page 8 for detailed descriptions of open and closed transfers. See page 7 for a detailed description of generator cool-down. See page 35 for information about the Line Stable setting.

See page 35 for information about the Min on Gen setting.

6 InfraStruXure Power Generation System