1785-MK

The 1785-MK module is an EEPROM nonvolatile memory module that works as a backup memory module for PLC-5 processors within the 1785 bulletin. This memory module has been designed and manufactured by Allen-Bradley. This nonvolatile memory backup mdule comes with a capacity of 8,000 words. "EEPROM" stands for "Electrically Erasable Programmable Read-Only Memory" and it can be programmed, erased, and reprogrammed electronically. The cells in this type of memory consist of MOS transistor celss. Generally, an EEPROM module can only be erased and reprogrammed between 100,000 and 1 million times, approximately.

The Allen-Bradley 1785-MK EEPROM nonvolatile module is shipped in a static-shielded bag to protect it against electrostatic damage. Before handling this memory module, the users need to discharge themselves of static electricity If the module is going to be stored, it needs to be stored in a static-shielded bag. The module comes by default with the jumper in the position that is used to write data to the EEPROM. If the jumper is removed from the 2 pins, it is impossible to write any data to the module. To install the Allen-Bradley 1785-MK EEPROM nonvolatile module, the power needs to be removed from the I/O chassis, and if it is inserted with power on, this can result in a loss of power and memory and even in a processor fault. To be properly installed, the latch of the I/O needs to be lifted and then the EEPROM can be firmly pushed into the processor until it is flush with the bottom of the processor.