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PLC: Memory Card

FAQ No. FAQ02890

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How are Memory Cards usually used with CS1/CJ1 Programmable Controllers?


The main applications of Memory Cards are as follows:

1.Program files, data files, and parameter files can be saved to the Memory Card and then the files can be automatically transferred from the Memory Card to RAM in the CPU Unit when the power is turned ON. This allows for highly reliable use of ROM-based operation.

2.By turning ON a bit in the Auxiliary Area while the ladder program is being executed, the entire program can be replaced. In this way, computer programs exceeding the total amount of memory available in the CPU Unit can be stored on the Memory Card. Then, programming required for different production lots or production model control can be loaded to the CPU Unit as necessary.

3.Using the File Write command, data files can be transferred between the CPU Unit and a Memory Card while the Programmable Controllers are operating. By using this function, up-to-date production information and quality control data can be stored temporarily in the DM or EM Area and saved to the Memory Card as a single file with unique file names. The files can also be read to the DM or EM Area to restore the same information.

Also, the Memory Card can be removed even when power is being supplied to the CPU Unit, so data can be exchanged with personal computers or spreadsheet software while the Programmable Controllers are operating.