Can run 1214C AC/DC/RLY Plc without memoty card.

HI

I have done one automation in my plant by third party. They Used 1214C AC/DC/Rly cpu with Memory Card. I have have very limited no's of I?O. So is it possible to use cpu without memory card? I recently lost my memory card so anybody can help?

Hello Robin;

First read this quick description of the S7-1200 CPUs memory concept, from this essential manual:

SIMATIC S7 S7-1200 Programmable controller

https://support.industry.siemens.com/cs/ww/en/view/109478121

4.1.5 CPU memory

Memory management

The CPU provides the following memory areas to store the user program, data, and configuration:

● Load memory is non-volatile storage for the user program, data and configuration. When you download a project to the CPU, the CPU first stores the program in the Load memory area. This area is located either in a memory card (if present) or in the CPU. The CPU maintains this non-volatile memory area through a power loss. The memory card supports a larger storage space than that built-in to the CPU.

● Work memory is volatile storage for some elements of the user project while executing the user program. The CPU copies some elements of the project from load memory into work memory. This volatile area is lost when power is removed, and is restored by the CPU when power is restored.

So what you need to know is whether without a memory card you have enough integrated load memory in your CPU to download a program to the PLC.

Now, look at the attached screencapture, extracted from the CPU 1214C Technical data; it shows that this CPU model has on-board load memory of 4 MB, even without a memory card. So you should be able to download your program to the CPU without a problem.

Hope this helps,

Daniel Chartier