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What happens to the M340 or M580 if the CPS reset button is pressed?

Issue
What are the implications of pressing the CPS reset button?

Product line
Modicon M580 M340

Resolution
The M340/M580 will go through a 'Cold Start' so the retention of its Data and the Run / Stop condition will be dependent of the configuration settings. The CPU could come up running or stopped and with either initial or last values.

This button is not intended to be used for a standard power cycle or cold start. When the button is pressed, all of the modules in the backplane go to a '0' state. This includes the CPU and any other modules. Everything running in the CPU is wiped out and reloaded from backup. If you are using %S94 in logic and intend on using this button, make sure to make a copy of current values using the Transfer Data to File tool before pressing. If the CPU does not go into Run automatically, all modules in the backplane will remain unconfigured, this includes modules such as NOC/NOE modules which would no longer communicate.