7 PROFIBUS DP Communication
7.3 SIMATIC S7 project
General PLC reset
Operating a PLC
with a new
If the current operating status of the PLC is displayed, the MPI connection oper-
If the current status of the PLC is not displayed, first check the MPI interface for
correct parameterization. If no connection is established to the PLC despite cor-
rectly set MPI interface, an overall reset of the PLC must be carried out.
General reset of the PLC can be performed using 840Di Start-up or HMI Ad-
– Start 840Di start-up: Windows NT taskbar > Start > Programs >
SINUMERIK 840Di > 840Di start-up.
– Open the dialog box: Menu command Window > Diagnosis > NC/PLC.
HMI Advanced (840Di SW 2.2 and higher and HMI Advanced SW 6.2)
– Open the dialog box: Operating area switchover > Start-up > NC/PLC
To initiate a general PLC reset, activate the button: "MRES".
At completion of this general reset, the PLC is in the RUN state (RUN LED lights
The configuration is loaded in "HW Config" using the menu command Target
system > Load into module.
For loading a configuration, the PLC must be in the STOP state. If "HW Config"
detects on loading that the PLC is still in the RUN state, a dialog box will appear
where you can set the PLC to the STOP state.
From the dialog box "Choose Target Module", choose the module into which
you want to load the current configuration. In this case: PLC315-2DP M/S
Dialog: Choose Target Module
Module: PLC315-2DP M/S 2AF03
To load the configuration, put the PLC in the STOP condition. The STOP condi-
tion of the PLC is interpreted by the NC as a failure of the PLC, and an appropri-
ate alarm response is output.
After the configuration has been loaded into the PLC successfully, for resyn-
chronization of NC and PLC, NC reset must be initiated, e.g. using 840Di
Start 840Di start-up
– Windows NT taskbar: Start > Programs > SINUMERIK 840Di > 840Di
Carry out NC reset
– Menu command: Window > Diagnostics > NC/PLC
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SINUMERIK 840Di Manual (HBI) – 06.03 Edition