Siemens SIMATIC ET 200AL, System Manual

Page: 1527 / 2255

Diagnostics and fault correction
13.2 Emergency address
Communication
406
Function Manual, 05/2021, A5E03735815-AJ
Diagnostics with the user program
When you program the T_DIAG instruction, you can evaluate diagnostic information about
the configured and programmed connections of the CPU using the user program.
Additional information
You will find the description of the web server functionality in the function manual Web
server ( http://support.automation.siemens.com/WW/view/en/59193560 ).
13.2 Emergency address
If you cannot reach the CPU via the IP address, you can set a temporary emergency address
(emergency IP) for the CPU. Via this emergency address, you can re-establish the connection
with a CPU in order to load a device configuration with a valid IP address.
You can set an emergency address regardless of the protection level of the CPU
When do you need an emergency address?
Your CPU cannot be reached in the following cases:
•
The IP address of your PROFINET interface is assigned twice.
• The subnet mask is set incorrectly.
Requirements
• You have selected "Set IP address in the project" for the IP protocol in the device
configuration in STEP 7.
• The CPU is in STOP mode.
Restoring a valid device configuration with an emergency address
1. Set the emergency address for the interface of the CPU with a DCP tool. For example, the
SIMATIC Automation Tool has a DCP command "Define IP address".
The maintenance LED of the CPU lights up. The diagnostic buffer also shows that an
emergency address was activated for an Ethernet interface.
2. Load a STEP 7 project with a valid IP address into the CPU.
3. Switch the CPU off and on again.
The emergency address is reset.
Result
The CPU starts up with the valid IP address.