What do you have to do if, after adding a CP or an FM module, the SIMATIC S7-300 CPU no longer switches to RUN mode?
When adding a CP or an FM module you normally proceed as follows.
- You enlarge the SIMATIC S7-300 station physically with a CP or the FM module.
- In STEP 7 you change the hardware configuration to accommodate the new module.
- You load the changed system data into the CPU in STOP mode.
- You switch the CPU to RUN mode.
The S7-300 CPU remains in STOP mode. This behavior is signaled as follows:
- The "SF" LED lights red (sumcheck error).
- The following events are displayed in the diagnostics buffer:
- Event ID 16# 49A0
STOP because of parameter error or impermissible difference between setpoint and actual configuration: Startup inhibit
- Event ID 16#5962
Parameter error with start inhibition in party line/K bus parameters
Error type: I/O bus not OK, which means that a module does not enter a type ID within the module monitoring time.
- Event ID 16#6547
Parameter error when parameterizing modules (not via P bus, but abort of download)
The K bus configuration is evaluated by the CPUs listed in Table 1 only at Power OFF/ON and Overall Reset. This evaluation is not made when the system data is simply loaded into the station. Configured modules that use the K bus therefore cannot be reached by the CPU. This can lead to the above-mentioned events in the diagnostics buffer.
Execute the following steps to analyze the cause of this parameterization error:
- Switch the power supply off and on again.
- Do an overall reset of the S7-300 CPU. The system data is loaded from the MMC (Micro Memory Card) into the RAM.
- Load the configuration offline, for example with a PG/PC, to the MMC (Micro Memory Card) and then use the MMC in your S7-300 CPU.
- Check whether the CP 343-1 is networked in the hardware configuration.
- Save the project with the option "With reorganization (slow)", erase the MMC (Micro Memory Card) of the S7-300 CPU and slot the erased MMC (Micro Memory Card) back in the S7-300 CPU and load the project into the S7-300 CPU.
- Export the hardware configuration and import the hardware configuration into a new STEP 7 project. Execute the following steps:
- Compile the hardware configuration
- Copy all the blocks of the user program into the new STEP 7 project.
- Check the connections in NetPro. If necessary, add connections in NetPro.
- Check the IMs by replacing the IMs or slotting the CP into the individual IMs. See whether the behavior re-occurs. The event 16#6547 in the diagnostics buffer indicates that one of the IMs is defective.
Table 1 shows an overview of the S7-300 CPUs that are affected by this behavior.
|S7-300 CPU||Article number||Firmware version|
|CPU 315-2 PN/DP||6ES7315-2EG10-0AB0||< V2.3.4|
|CPU 317-2 DP||6ES7317-2AJ10-0AB0||< V2.1.10|
|CPU 317-2 PN/DP||6ES7317-2EJ10-0AB0||< V2.3.4|
|CPU 315T-2 DP||6ES7315-6TG10-0AB0||≤ V2.4.1|
|CPU 317T-2 DP||6ES7315-6TJ10-0AB0||≤ V2.4.1|
|CPU315F-2 PN/DP||6ES7315-2FH10-0AB0||< V2.3.4|
|CPU 317F-2 DP||6ES7317-6FF00-0AB0||< V2.1.10|
|CPU 317F-2 PN/DP||6ES7317-2FJ10-0AB0||< V2.3.4|
The behavior occurs with all K-bus users, i.e. with the Ethernet and PROFIBUS CPs and function modules FM353, FM354, FM355 S/C and FM357(-2), for example.