Schneider Electric 840 USE 106 0 manual Overview of Quantum Hot Standby, Purpose, What’s in this

Overview of Quantum Hot

Standby 1

At a Glance

Purpose	This chapter presents a brief overview of the Hot Standby system, including a
	description of Primary and Standby control, components, the Hot Standby module,
	LEDs and switches, modes of operation, 984 and IEC HSBY, and the application
	size.
	Throughout the rest of this book the Quantum Hot Standby system is referred to as
	HSBY.
	An HSBY system is based on two identically configured programmable logic
	controllers linked to each other and to the same remote I/O network. If one controller
	fails, the other assumes control of the I/O system.
What’s in this
	This chapter contains the following sections:
Chapter?
	Section	Topic	Page
	1.1	Control	15
	1.2	Operation	21
	1.3	Cabling	23
	1.4	984 HSBY and IEC HSBY	26

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