Using A Memory Card With The S7-1200 Fail-Safe Cpu - Siemens SIMATIC S7 Functional Safety Manual

A.2.1.6

Using a memory card with the S7-1200 Fail-Safe CPU

The S7-1200 memory card used as a transfer card is a way to copy a program into the PLC
Internal Load Memory (ILM) without a connected TIA Portal. You remove the transfer card
after program installation, and subsequent power cycles use the program stored in the ILM.
A memory card used as a program card keeps the PLC program on the card. If you remove
the memory card, the ILM is empty, and there is no program in the PLC.
Refer to the S7-1200 Programmable Controller System Manual
(http://support.automation.siemens.com/WW/view/en/91696622) for general instructions for
creating and using transfer cards and memory cards. The S7-1200 fail-safe CPU behavior
when using a memory card has some differences from the standard CPU:
● When the S7-1200 fail-safe CPU starts with no memory card and the ILM is empty, the
fail-safe CPU's STOP and MAINT LEDs flash for three seconds. This provides a
temporary visual indication that the ILM is empty. The TIA Portal or a memory card must
be used to load a user program.
● When the fail-safe CPU starts with a program memory card installed and the ILM is not
empty, the fail-safe CPU erases the ILM and then stops, flashing the STOP and MAINT
LEDs. This is a visual indication that the ILM is erased and that the fail-safe CPU is
waiting for a power cycle or a memory reset command in order to continue. Continuation
and subsequent power cycles load the program from the memory card.
● When the fail-safe CPU starts with an empty memory card installed and the ILM is not
empty, the fail-safe CPU copies the program from the ILM to the memory card. The fail-
safe CPU then erases the ILM and stops, flashing the STOP and MAINT LEDs. This is an
indication that the ILM is erased and that the fail-safe CPU is waiting for a power cycle or
a memory reset command in order to continue. Continuation and subsequent power
cycles load the program from the memory card.
● When the fail-safe CPU starts with a transfer memory card installed and the ILM is not
empty, the fail-safe CPU erases the ILM and then stops, flashing the STOP and MAINT
LEDs. This is a visual indication that the ILM is erased and that the fail-safe CPU is
waiting for a power cycle or a memory reset command in order to continue. Continuation
copies the user program from the memory card to the ILM, and then the fail-safe CPU
stops, with the STOP LED on and the MAINT LED flashing. At this point, you must
remove the transfer memory card and then power cycle or command a memory reset in
order to continue. Continuation and subsequent power cycles load the program from the
ILM.
S7-1200 Functional Safety Manual
Manual, 02/2015, A5E03470344-AA
Technical specifications
A.2 Fail-Safe CPU technical specifications
147