MVI56E-MCMR PROSOFT

Model: MVI56E-MCMR
Brand: PROSOFT Technology
Series: ControlLogix Enhanced Modbus (E-series)
Core Function: Modbus RTU/ASCII master or slave with reduced backplane data block
Product Type: In-rack Modbus communication module
Key Specs: 2 serial ports | RS-232/422/485 | 5,000-word Modbus database | Reduced I/O block
Condition: New Original (New Surplus)

Product Introduction

PROSOFT MVI56E-MCMR is an Enhanced Modbus Master/Slave communication module with a reduced backplane data block for Rockwell 1756 ControlLogix systems, intended mainly for remote chassis and ControlNet architectures where backplane and network bandwidth are constrained. It appears to the CPU as a specialty I/O module and presents Modbus data as I/O words.

The module provides two independent serial ports that support Modbus RTU/ASCII over RS‑232, RS‑422, or RS‑485, sharing a user‑defined Modbus register database while using a smaller I/O image than the standard MVI56E‑MCM, which makes it better suited for remote racks while still avoiding external Modbus gateways. Verify that your controller firmware and network design justify choosing the MCMR variant instead of the full‑block MCM.

Frequently Asked Questions (FAQ)

Q: Does the MVI56E-MCMR support hot-swapping in a ControlLogix rack?
A: Honestly, the hardware and chassis support online insertion/removal, but your process may not. I recommend inhibiting the module in the Logix project, confirming that no critical interlock depends on its data, and only then swapping it during a controlled window. Treat it the same as other high‑current 1756 communication modules and avoid pulling it with marginal power supplies or unstable networks.

Q: Is the MVI56E-MCMR obsolete, and is there a direct replacement?
A: The most common mistake is assuming the MVI56E‑MCM and MVI56E‑MCMR are drop‑in equivalents. The MCMR exists specifically for reduced backplane I/O usage, usually for remote racks. If PROSOFT later flags it as legacy, they typically point to an E‑series or XT variant; always check their current lifecycle notice and confirm any suggested successor supports the reduced data block behavior before you treat it as a one‑for‑one replacement.