Description
Key Technical Specifications
- Model Number: MVI56-MCM
- Manufacturer: ProSoft Technology
- Series: ControlLogix Platform Communication
- Module Type: Modbus Master/Slave Serial Interface
- Backplane: 1756 ControlLogix Single Slot
- Ports: 2x Independent Serial Ports (DB9)
- Protocols: Modbus RTU, Modbus ASCII
- Data Memory: 10,000 x 16-bit Register Database
- Power Req: 800 mA @ 5VDC Backplane
- Config: RSLogix 5000 Add-On Instruction (AOI)
Functional Role & Application Analysis
The ProSoft MVI56-MCM is the industry-standard bridge between Allen-Bradley ControlLogix processors and legacy Modbus serial devices. Its core role is to make external RTU/ASCII data appear as local I/O to the PLC. This solves a critical integration problem: connecting modern ControlLogix systems to older drives, meters, and RTUs without replacing the entire field network. The module handles all protocol conversion asynchronously, so PLC scan time remains unaffected.
Typical use cases include:
- Legacy Device Integration: Connecting old Modbus RTU flow meters, temperature controllers, or VFDs to a new ControlLogix controller.
- Distributed Serial Networks: Using both ports to create two separate Modbus networks from a single rack slot.
- System Maintenance: Replacing failed MVI56-MCM units in existing plants without reprogramming, as the AOI structure remains consistent.
Our Quality Standard & Testing Process
We understand that a communication module failure means lost data and potential process upset. A module that powers up but drops packets is worse than one that doesn’t power up at all. We have established a rigorous testing process to ensure every MVI56-MCM we ship communicates flawlessly.
- Backplane Power Test: Every module is installed in a live 1756 rack to verify it draws correct current and doesn’t cause backplane voltage sag.
- Serial Port Loopback: We perform loopback tests on both DB9 ports to verify TX/RX integrity and baud rate accuracy up to 115.2 kbps.
- Live Modbus Poll: The module is configured as a Master and polls a test slave device for 24 hours to verify zero error counts and stable register mapping.
- Warranty Backing: Only modules that pass all communication stress tests are approved for shipment. Every unit is backed by our full 12-month warranty.
ProSoft MVI56-MCM
Compatibility & Migration Paths
To ensure this MVI56-MCM is 100% compatible with your system, you must check these key compatibility points. Communication modules are unforgiving of configuration mismatches.
- MVI56E Upgrade Path: The newer MVI56E-MCM is a direct drop-in replacement with enhanced Ethernet diagnostics. If you’re replacing multiple units, consider the upgrade for remote configuration via CIPconnect.
- AOI Version Match: Verify your RSLogix 5000 AOI version matches the module firmware. Mismatched AOIs cause “Module Not Configured” faults even with good hardware.
- Memory Mapping: Confirm your existing program uses ≤10,000 registers. Exceeding this limit causes silent data corruption.
- Get Expert Help: Unsure about AOI versions or migration to MVI56E? Contact our technical team today for a free compatibility check. Send your current AOI version and module serial number, and we’ll verify the match.
