How to make adjustments after a hardware change
A change to the hardware always requires a change to the software. Configure the hardware
changes in HW Config. Compile the changes and then download the data to the CPU. You
can then physically replace, remove or add the modified hardware.
1. Open the project (the AS) in HW Config.
2. Drag the object (such as the CPU: Type, Firmware Version x.x) from the hardware catalog
3. After verification, click "Yes" to confirm.
4. Select the menu command Station > Save/Compile.
Updating the CPU
Compare the type and manufacture date of the modules you are using with the information in
If replacement of the CPU is required, contact your Siemens representative.
Firmware update for CPU S7-400H
In a fault-tolerant PCS 7 system, the (S7-400H) CPUs must always have a uniform hardware
version and the same firmware version.
Update capability of CPUs
The online update of the firmware can be performed using the procedure described below as
of the following firmware versions:
● CPU S7-400H as of firmware version 4.5
● CPU S7-400 as of firmware version 5.0
Service support and diagnostics (V8.0)
Service Manual, 03/2012, A5E02779775-02
and drop it into the appropriate slot in the AS configuration table.
The following message appears: "Do you want to exchange component ... with
You can also perform the compiling during the subsequent work.
PCS 7 Released Modules.
As of firmware version 4.5, the firmware can be updated in RUN mode.
3.3 Hardware update