OVERVIEW

Official designation: Allen-Bradley 1775-MEA (PLC-3, Error-Correcting RAM Memory Module)

Role/Application: This single-slot module provides 64K words of volatile RAM program and data storage for the PLC-3 controller, utilizing Error Correction Code (ECC) for reliable data integrity.

KEY SPECS SUMMARY

Power: 5 V DC and 15 V DC from chassis backplane

Interfaces / Ports: Backplane connector

Indicators: Refer to the latest manufacturer manual.

Operating Temp: 0 to 60 degrees C

Platform / Compatibility: PLC-3 processor system, single slot chassis mount

Limit: Capacity is 64K 16-bit words

Lifecycle: Discontinued/Obsolete

FREQUENTLY ASKED QUESTIONS

Technical Specifications:

Q: What is the primary data storage capacity of the 1775-MEA module?

A: The module provides a storage capacity of 64K 16-bit words of volatile RAM.

Wiring & Installation:

Q: What power source is utilized by the 1775-MEA memory module for operation?

A: The module is powered by the 5 V DC and 15 V DC circuits supplied through the PLC-3 chassis backplane.

Troubleshooting & Compatibility:

Q: What is the purpose of the error-correcting feature in the 1775-MEA module?

A: The ECC feature is designed to automatically detect and correct single-bit errors in the stored memory data.

Replacement & Upgrades:

Q: What is the current recommended Allen-Bradley PLC platform migration path from the obsolete PLC-3 system?

A: The recommended upgrade path for the PLC-3 is migration to the modern Allen-Bradley ControlLogix platform.