Dears

we have a s7-400 cpu and have an issue related to memory reset. although I change its backup batteries with new ones, it is lost its battery after power failure still, is it power supply issue? and do i need to replace the power supply with new one

hi,

have you depassivated the battery after changing?

have a look in the S7-400 module data manual, chapter 3.3:

SIMATIC S7-400 S7-400 Automation System Module Data

To depassivate you may have to short-circuit the battery.

hope this helps,

Dear Namchinbum

Did the battery fault was disappeared after you replaced the battery and put the battery in 2battery switch.

If fault was there than you need to short the battery terminal and have to put in battery slot.

Hi,

Did you aknowledged the batteries fault by moving switch batteries selector on OFF and on 1 or 2 batteries monitoring ?

Regards.