When an FX PLC is turned from RUN to STOP data is normally reset.  So can you make the PLC data retentive if you do not want “loose” the PLC data?  The answer is yes.

And this is how you do it…..

In all FX PLCs there is a special bit register M8033 and if this is set ON it will make the PLC data retentive. This bit register can either set ON at the beginning of the PLC program (thus making the data retentive all the time – see example below) or set ON as and when required.

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