Battery inidcator and memory reset

Hi all,

I would like to ask about your opinions or maybe experiences in regard to following:

Is it true that the battery support for the S7400 unit will only work if the BATT.INDC switch is set to OFF. I know it sound very strange but I remember reading it somewhere in the Siemens manual, which I cannot find anymore. I also remember that I've tried it once and it was actually true.

I've already checked all availible documents but couldn't find anything, Siemens support are reffering me to the docus.

Would really appreciate any response.

Thanks!