The 1747-M2 is a memory module compatible for use with Allen-Bradley SLC 500 Fixed style and Modular hardware style Programmable Logic Controller (PLC). This memory module has an integrated 4K of user back-up memory. It is installed to any Fixed style controller such as 1747-L30A, 1747-L30C, 1747-L40A, and 1747-L40C. It is also compatible with modular hardware style controller such as SLC 5/01 with part numbers 1711-L511 and 1747-L514; SLC 5/02 with part numbers 1747-L524.

This module is sensitive to electrostatic discharge. It must be handled only from the edges and the the working area including must be free from oil and dirt. If the product is marked with CE, it depicts that the particular item complies with applicable directives.

This memory module has a specific jumper J1 settings when being mounted to the processor. It must be mounted only when the processor is without power.

Memory modules are added to provide a non-volatile memory type. By adding this type of memory, the processor is protected with unwanted deletion of the program as the integrated memory supplied with each processor is of Random-Access Memory (RAM) type. RAM memory type, similar to other electronic devices, lose the stored data when power is removed. This is also true with the SLC 500 processors however, the RAM memory of the processors is retained by a Lithium battery with lifespan of Two (2) years.

When installing or removing this module, make sure that the power to the controller has already been turned off to prevent damaging the module or experiencing undesired processor faults. It is important that you hold it by the end of the carrier or the edges of the plastic housing because dirt and the skin oil is corrosive and may affect the metallic parts of the module. Also avoid subjecting the 1747-M2 module to areas with possible electrostatic charge, as this charge can alter or even destroy the memory.