Description
Product Overview
MVI56-MNET is a single-slot in-chassis communication interface module manufactured by ProSoft Technology for the Allen‑Bradley 1756 ControlLogix rack platform. It acts as a high-performance gateway, enabling ControlLogix PACs to exchange data with Modbus TCP/IP field devices, instruments, remote RTUs and third-party PLCs. This legacy module supports both Modbus TCP Client and Server operation over Ethernet.
Technical Specifications
| Item | Parameter |
|---|---|
| Catalog Number | MVI56-MNET (often referenced as 1756-MVI56-MNET) |
| Platform | 1756 ControlLogix single slot chassis module |
| Backplane Load | 800 mA @ 5 VDC; 3 mA @ 24 VDC |
| Ethernet Interface | 1 × 10/100 Base-T RJ45, auto MDI/MDI-X |
| Protocol | Modbus TCP/IP (Client / Server) |
| Supported Modbus Functions | 01,02,03,04,05,06,15,16 |
| Max Concurrent Modbus TCP Server Connections | Up to 16 TCP clients |
| Modbus Client Command List | 32 configurable read/write commands |
| Backplane Data Transfer | 0–250 input words, 0–250 output words |
| Operating Temperature | 0°C to 60°C (32°F to 140°F) |
| Storage Temperature | -40°C to 85°C |
| Humidity | 5% to 95% non-condensing |
| Display & LEDs | 4-character scrolling alphanumeric LED; OK, APP, ERR status indicators |
| Configuration Tool | ProSoft Configuration Builder (PCB) |
| Programming Environment | RSLogix 5000 / Studio5000 |
Key Features
- Seamless integration into standard 1756 ControlLogix backplane, works with L6x, L7x series controllers including 1756-L71.
- Dual role operation: Modbus TCP Client to poll remote slave devices, Modbus TCP Server so external Modbus masters can read/write ControlLogix tag data.
- Built-in diagnostics and status reporting via front panel LED and module display.
- Add-On Instructions (AOI) available for simplified tag mapping and fault handling inside Logix controller project.
- Isolated Ethernet port protects ControlLogix backplane from field network noise and transients.
- Direct replacement upgrade path to newer MVI56E-MNET enhanced version with backward compatibility for existing logic.
Typical Applications
- Oil & gas, water / wastewater treatment plants
- Power generation and substation remote I/O and instrument communication
- Factory automation, packaging, material handling
- Connecting flow meters, pressure transmitters, VFDs, analyzers to ControlLogix PLC
- Legacy system integration between Rockwell ControlLogix and Modbus TCP third-party controllers
Installation & Maintenance Notes
- Install into any empty slot of standard 1756 ControlLogix chassis; avoid placing adjacent to high heat generating modules.
- Use CAT5e or better shielded Ethernet cable for Modbus TCP field network.
- Configure module parameters via ProSoft Configuration Builder, download configuration to module.
- Import the supplied AOI into Logix project to handle data transfer and module health monitoring.
- Check front panel LED and 4-character display for IP address, firmware version and fault codes during commissioning and troubleshooting.
- MVI56-MNET is end-of-life legacy hardware; consider MVI56E-MNET as modern drop-in replacement for new spare procurement.
- Always back up module configuration file and PLC program before firmware updates or online edits.
FAQ
Q: What is the difference between MVI56-MNET and MVI56E-MNET? A: MVI56-MNET is original legacy version. MVI56E-MNET is enhanced successor, supporting CIPconnect, improved diagnostics and higher performance, backward compatible for existing ladder logic.
Q: Does MVI56-MNET support Modbus RTU? A: No, this module is Modbus TCP/IP only. Use MVI56-MCM for Modbus RTU/ASCII serial communication.
