Dear All;;

could any one please answer me, why in most of Siemens  PLC's there is no back up batteries!!!

help please

best regards

Abdelrazek

Dear All;;

could any one please answer me, why in most of Siemens  PLC's there is no back up batteries!!!

help please

best regards

 Old Siemens PLC's have batteries, because of the memory architecture. Nowadays the currently used memory architecture in the modern PLC's, doesn't need backup batteries.

Hello Abdelrazak;

Battery support is required when the memory substrate are based on RAM chips or cards.

When the PLC uses Flash memory cards, no battery support is required,

See the technical data of a S7-1200 CPU, S7-1500 CPU or Sinamics drive memory card, below.

Hope this helps,

Daniel Chartier

Hi,

yes, lifetime of MC ist about 10 years if the number of delete/write procedures is <50,000 /year.

I think this FAQ is also interestng in context.

How do you calculate the service life of a memory card of the S7-1500/S7-1200 and ET 200?

Regards,

Towome

For the s7-1200, a battery pack module is available that only provided power to the real-time clock.  After a few days of the PLC powered off, the RTC resets to factory default value.  With the battery pack, it lasts much longer, to a very reasonable time frame.  I can see uses for that when shipping a machine from OEM to customer, or when the equipment is being relocated or will have an extended power off condition..

Abdelrazek

Dear All;;

could any one please answer me, why in most of Siemens  PLC's there is no back up batteries!!!

help please

best regards