CPU315-2DP MMC problem

Hi all,

I am using PLC 315-2DP with MMC  512Kb, but when I change my code and download to PLC, it says " insufficient memory space or work memory on the module" (pls see attached picture). I see in some same topics said need to replace new PLC but I not sure it is PLC or MMC problem because MMC memory is larger than my PLC program.  

Thank for your reply.

Striker77

Hi all,

I am using PLC 315-2DP with MMC  512Kb, but when I change my code and download to PLC, it says " insufficient memory space or work memory on the module" (pls see attached picture). I see in some same topics said need to replace new PLC but I not sure it is PLC or MMC problem because MMC memory is larger than my PLC program.  

Thank for your reply.

 Hi,

 You don't have any memory problem with the Load Memory, which means there is enough free space in  the MMC card. 

 The Retentive work memory in the CPU(Which cannot be increased without replacing the CPU) is full.  Retentive work memory used to get filled with Data  Blocks. Sometime the existing non used Data  Blocks also can occupy the Work Memory.

Try to delete all blocks from from the PLC and re download the backup. To delete the entire Memory of the CPU, Open Simatic Manager => Go to View Menu => Select 'Online'. Delete All blocks and SDB under the Blocks folder. After deleting the files, reload the backup again from the offline program.  

Please look at the given link for the S7 300 PLC's Memory Concept for better  understanding.

 Hi Saravana kumar

Thank you for your answer.  I 'll do as you suggest, hope it will be OK  

Saravana kumar

 

Striker77

Hi all,

I am using PLC 315-2DP with MMC  512Kb, but when I change my code and download to PLC, it says " insufficient memory space or work memory on the module" (pls see attached picture). I see in some same topics said need to replace new PLC but I not sure it is PLC or MMC problem because MMC memory is larger than my PLC program.  

Thank for your reply.

 Hi,

 You don't have any memory problem with the Load Memory, which means there is enough free space in  the MMC card. 

 The Retentive work memory in the CPU(Which cannot be increased without replacing the CPU) is full.  Retentive work memory used to get filled with Data  Blocks. Sometime the existing non used Data  Blocks also can occupy the Work Memory.

Try to delete all blocks from from the PLC and re download the backup. To delete the entire Memory of the CPU, Open Simatic Manager => Go to View Menu => Select 'Online'. Delete All blocks and SDB under the Blocks folder. After deleting the files, reload the backup again from the offline program.  

Please look at the given link for the S7 300 PLC's Memory Concept for better  understanding.

 Hi Saravana kuma,

Thank you for your reply, I 'll do as you suggest, hope it will be OK.