Hello,

I would like someone to clarify, if the MRES position of CPU switch (under the STOP position) is only for memory reset, i.e. you have to do all of the steps to reset the memory, or, if it has any other function, e.g. if you switch the CPU mode in the way: RUN - STOP- MRES (only 1 sec.) - STOP - RUN.

Thank you

Hi.

Not only for memory reset.

Formatting the MMc and Backing up firmware are the 2 what it can be uesed,too.

Best regard

LukasKrejci

Hello,

I would like someone to clarify, if the MRES position of CPU switch (under the STOP position) is only for memory reset, i.e. you have to do all of the steps to reset the memory, or, if it has any other function, e.g. if you switch the CPU mode in the way: RUN - STOP- MRES (only 1 sec.) - STOP - RUN.

Thank you

 Hi, LukasKrejci

Open the document:

S7-300 CPU 31xC and CPU 31x: Installation

See the points below.:

1. "8.4.3 CPU memory reset by means of mode selector switch"

2. "8.4.4 Formatting the Micro Memory Card"

3. "9.2 Backing up firmware on a SIMATIC Micro Memory Card"

4. "9.5 Resetting to the Delivery State"

In general, to reset the memory and to format the memory card (I personally did both, it works fine)

entnces si bajo en interruptor a MRES solo unos segundos y regreso a run no se me borra el programa ?

Este solo se borra si se deja mas tienpo en mres,cierto? 

Hello LUIS EDUARDO VI AL,

welcome to the community!

Please try to discuss your question in English language. This is an international community, and we try to focus on one language. Posting in English will help you to get more response to your question.

This is the translation of your question:

LUIS EDUARDO VI AL

So if I lower the switch to MADRES for just a few seconds and return to run, won't the program be deleted?

This is only erased if it is left for more time, right?

 Regards,
Jen_Moderator