What is the difference between S7-400, S7-300 and IM151-8 PN/DP CPU modules

one query.

What is the difference between S7-400, S7-300 and IM151-8 PN/DP CPU modules.

Does the S7-400 have some internal memory. because when we commissioned for our internal company training last month, i have not installed Memory card. and i had no such problem.

Does S7-300 and IM151-8 PN/DP CPU require memory card.

please reply in brief, want to know, so that i can explain in internal company training.

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Split from The system data cannot be loaded to module IM151-8 PN/DP CPU.

Hello,

yes S7-400 can have internal loadmemory and need no Memcard.

S7-300 end ET200 based PLC need the MMC for load memory, without it no download possible.

Regards

Christoph

thank you Christoph that would be all I needed.

Regards,

Rahul

hi,

have a look here:

How can you obtain an overview of the memory concept of SIMATIC S7-300 CPUs and C7 devices?

How can I get an overview of the S7-400 memory concept?

IM151-8 is like a S7-300 CPU.

hope this helps,

regards,