Siemens SIMATIC S7-400H - Configuration, Programming and Diagnostics

Converting from S5-H to S7-400H
C-2
Automation System S7-400H Fault-tolerant Systems
A5E00068197-07
C.2 Configuration, Programming and Diagnostics
Configuration
In STEP5, configuration was performed with a separate configuration package –
for example, COM 155H.
In STEP 7 we use the standard software in conjunction with the option package
“S7 H Systems” to configure the fault-tolerant CPUs. Using SIMATIC Manager,
create a fault-tolerant station and configure it with HWCONFIG. The special
features of the fault-tolerant CPUs are summarized in a few registers. The
integration in networks and the configuration of connections are performed with
NetPro.
Diagnostics and programming
Error diagnostics on the S5 is implemented with the help of the error data block,
into which the system enters all errors. The error OB 37 is started automatically for
every entry. Further information has been stored in the H memory word.
The H memory word consists of a status byte and a control byte. Control
information can be set bit by bit in the STEP5 user program.
In STEP 7, system diagnostics is accomplished by means of the diagnostics buffer
or by displaying what are known as partial lists from the system status list (specific
information for fault-tolerant systems, for example, are located in SSL71). This
check can be performed with the help of the programming device or by the user
program with SFC 51 “RDSYSST”.
OB 70 and OB 72 are available for I/O redundancy loss and CPU redundancy loss,
respectively.
The function of the control byte is implemented in STEP 7 by means of the SFC 90
H_CTRL.
Subject with S5 Equivalent in S7
Error OB37 Error OBs OB 70 and OB 72
Memory control word SFC 90 “H_CTRL”
Memory status word SZL71
Error block Diagnostics buffer