Hi,

We have several system consisting of 2x PS 407 10A and 1x CPU 414-5H (with SRAM module, and latest firmware)
And we have experienced that the CPU often looses program even if the batteries seems to be good voltage when the system has been turned off for while (maybe months).
These are mobile systems that might be shut down for long times.

So my first question is if the power supplies need to be in the on position to maintain the program?
I did test this once for like 12 hours, and it did retain the program. But have not tried any longer than that.

I just had the issue again now, and voltage on both batteries for the PS in slot 1&2 was both above 3,6V, but BAT2F is orange (no other bat leds lit).
The second PS in slot 3&4 had one dead battery and one at around ~3,5V and none of the bat leds are lit?
Both PS are set up with the switch on 2 batt ind.

Any help appreciated.

Hi Nepa1982,

if you bought Siemens batteries there should be a document in the packaging that describes the installation procedure.  The crucial element in this procedure is the depassivation of the battery.  Failure to perform this procedure might be responsible for the lack of capacity of the battery.