i have a question about s7 200 plcs. some of plcs have eeprom slot and i have to make a "program memory cardridge" whenever i modify its program. are there any s7 200 plcs without eeprom card? what are the differences between cpu 222-224-226 ?
There's no need to use an eeprom cartridge. A program can be loaded directly into the internal flash memory of a S7-200 CPU. Other data like flags or datawords will be retained in RAM that is backed up for approximately 10 days, without the need of an extra backup battery.
The EEPROM cartridge is the little 'bump' just above the programming port. That same location can be used for a backup battery.
Check for catalogue ST70 on the Siemens website, using the link below: