1785-MJ

The 1785-MJ is an Allen-Bradley EEPROM module that serves as memory backup. The 1785-MJ is also compatible with 1772-LW (PLC-2/17); 1772-LWP (PLC-2/17); 1785-LT (PLC-5/10); 1785-LT2 (PLC-5/12); 1785-LT3 (PLC-5/15) and 1785-LT4 (PLC-5/25). The 1785-MJ is commonly used as a backup storage device for program files.

The Allen-Bradley 1785-MJ is a Programmable Logic Controller (PC) memory module. This module is compatible for use with the 1772-LW (PLC-2/17), 1772-LWP (PLC-2/17), 1785-LT (PLC-5/10), 1785-LT2 (PLC-5/12), 1785-LT3 (PLC-5/15), and 1785-LT4 (PLC-5/25) Programmable Logic Controllers (PLCs). It has an embedded 8K Words of non-volatile Electronically Erasable Programmable Read Only Memory (EEPROM).

The 1785-MJ is sensitive to electro-static discharge - therefore, proper module handling must be observed when installing this module. Before installing the module, the installation personnel should touch a grounded object to discharge static charge. Additionally, place the module to a flat, grounded object as well and store inside the provided anti-static shield bag. Prior to installation of this memory module, the backplane switch in the chassis must be appropriately set to define the behavior of the memory module - specifically, the transfer mode during processor start-up. Additionally, memory write protection is set by enabling the jumper installed at the side of the memory module.

The 1785-MJ memory module measures 2.18 L x 1.73 H x 0.69 D inches or 55.4 L x 43.9 H x 17.4 D milimeters. It has an operating temperature of 0 to 60°C (32 to 140°F) and storage temperature of -40 to 85°C (-40 to 185°F) with a relative humidity of 5 to 95% (without condensation).

This memory module does not support Removal and Insertion Under Power (RIUP). The host processor must be without power before inserting the module to the memory card slot. Failing to do so may damage the memory module and possibly erase the contents if already downloaded with user program.