Table 10-9 Example Of Redundant I/O, Ob 122 Part; Table 10-10 For The Monitoring Times I/O Used Redundantly - Siemens SIMATIC S7-400H System Manual

Table 10-9 Example of redundant I/O, OB 122 part
STL
L OB122_MEM_ADDR;
L W#16#8;
== I;
JCN M01;
SET;
= IOAE_BIT;
JU CONT;
M01: NOP 0;
L OB122_MEM_ADDR;
L W#16#C;
== I;
JCN CONT;
SET;
= IOAE_BIT;
CONT: NOP 0;
Monitoring times in link-up and update
NOTICE
If you have made I/O modules redundant and have taken account of this in your program,
you may need to add an overhead to the calculated monitoring times so that no bumps
occur at output modules.
An overhead is only required if you operate modules from the following table as redundant.

Table 10-10 For the monitoring times I/O used redundantly

Module type
ET200M: Standard output modules
ET200M: HART output modules
ET200M: F output modules
ET200L–SC with analog outputs
ET200S with analog outputs or technology modules
Follow the steps below:
● Calculate the overhead from the table. If you have used a number of module types from
● Add this to all the monitoring times calculated so far.
S7-400H
System Manual, 09/2007, A5E00267695-03
Description
// Does module A cause IOAE?
//Relevant logical base address
//Module A?
//If not, continue with M01
//IOAE during access to module A
//Set IOAE bit
// Does module B cause a IOAE?
//Relevant logical base address
//Module B?
//If not, continue with CONT
//IOAE during access to module B
//Set IOAE bit
the table redundantly, apply the largest overhead.
10.6 Other options for connecting redundant I/Os
Overhead in ms
2
10
50
≤ 80
≤ 20
Using I/Os in S7-400H
155