Maintenance
7-5
AutomationSystem S7-400 Hardwareand Installation
A5E00850741-01
7.3 Replacing CPUs
Slot Numbering
If you have provided the modules in your system with slot numbering, you must
remove the number from the old module when replacing it and apply the number to
the new module.

Saving the Data

Save the user program including configuration data.

Removing the Module

1. Setthe CPU mode switch to STOP.
2. Setthe standby switch of the power supply module to (0 V output voltages).
3. Removethe cover of the CPU.
4. Disconnectthe MPI connector, if applicable.
5. Disconnectthe connector at the EXT. BATT.socket, if applicable.
6. Removethe memory card.
7. Loosenthe mounting screws of the module.
8. Swingthe module out.