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Why M238 Controller donot RUN automatically after power recycle,if RUN/STOP input is configured.

Modicon M238 Controller do not go to RUN mode after power recycle because with more than 3 days without
power(and without external battery),the controller will stay in STOP mode at the next power ON because the
internal state of the controller( Stop or RUNNING)is included into the "few system internal variables" saved into
the RAM  (Random Access Memory)saved area during Power OFF procedure.
In this case,it is necessary to make a rising edge of the STOP/RUN input in order to run the application.
On the other hand,user can use the external battery to support a power Off up to 1 year (instead of 3days),without losing any data values.
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