Siemens Simatic S7-1500R System Manual page 319

Glossary
Primary-backup switchover
The primary CPU has the leading role within the redundant system. If the primary CPU fails
following a fault, the backup CPU takes over the primary role and operates as the primary
CPU.
Process image (I/O)
The CPU transfers the values from the input and output modules to this memory area. At the
start of the cyclic program, the CPU transfers the process image output as a signal state to
the output modules. The CPU then reads the signal states of the input modules into the
process image inputs. The CPU then executes the user program.
Product version (PV) = Function version (FV)
The product version or function version provides information on the hardware version of the
module.
PROFINET
PROcess FIeld NETwork, open Industrial Ethernet standard that continues PROFIBUS and
Industrial Ethernet. A cross-manufacturer communication, automation, and engineering
model defined by PROFIBUS International e.V. as an automation standard.
PROFINET IO
Communication concept for the realization of modular, distributed applications within the
scope of PROFINET.
PROFINET IO controller
Device used to address connected IO devices (for example distributed I/O systems). The IO
controller exchanges input and output signals with assigned IO devices. The IO controller is
often the CPU on which the user program is running.
PROFINET IO device
Distributed field device that can be assigned to one or more IO controllers. Examples:
Distributed I/O system, valve terminals, frequency converters, switches
Push-in terminal
Terminal for the tool-free connection of wires.
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S7-1500R/H redundant system
System Manual, 10/2018, A5E41814787-AA