Siemens SIMATIC S7-400H Manual page 187

Separate Operation
Overview
The present appendix provides the information necessary for separate operation of
a CPU 417-4H. You will learn in the following
how separate operation is defined
when separate operation is necessary
what you have to take into account with separate operation
how the H-specific LEDs respond
how you configure a CPU 417-4H for separate operation
how you can expand it to form a fault-tolerant system
The differences compared to a standard S7-400 CPU that you have to take into
account when configuring and programming the CPU 417-4H are contained in
Appendix D.
Definition
By separate operation, we understand use of a CPU 417-4H in a standard
SIMATIC-400 station.
Reasons for separate operation
The following applications are only possible with a CPU 417-4H – in other words,
they are not possible with standard CPUs in the S7-400 range.
Use of fault-tolerant connections
Configuration of the S7-400F fail-safe programmable logic controller
A fail-safe user program can only be compiled as an executable when using
the CPU 417-4H with a fail-safe runtime license (for more information refer to
the manual Programmable Logic Controllers S7-400F and S7-400FH Fail-Safe
Systems .).
Note
The CPU 417-4H self-test can also be performed in separate operation.
S7-400H Programmable Controller Fault-Tolerant Systems
A5E00068197-04
B
B-1