Description
1. Product Overview
The MVI69-MCM is a Modbus Master/Slave communication module developed by ProSoft Technology for Allen-Bradley (Rockwell Automation) 90-70 series Programmable Logic Controllers (PLCs). It installs as a daughterboard directly onto the PLC backplane, occupying the same slot as the module it pairs with — no extra I/O slot is required. This allows 90-70 series PLCs to gain powerful Modbus communication capabilities, enabling seamless interconnection with VFDs, instruments, sensors, third-party PLCs, and any device that supports the Modbus protocol.
ProSoft Technology is a well-known communication solutions provider in the industrial automation industry, specializing in developing communication modules for Rockwell Automation, Schneider, and other mainstream PLC systems. Their product line covers virtually every major industrial protocol including Modbus, PROFIBUS, EtherNet/IP, DF1, DNP3.0, and HART. The MVI69-MCM is one of the core models in their Modbus product line for AB 90-70 PLCs.
Allen Bradley ProSoft MVI69-MCM MVI69 Modbus
Key Features and Advantages
1. Dual Master/Slave Mode — Flexible Switching
The biggest highlight of the MVI69-MCM is that it supports both Modbus Master and Modbus Slave operating modes simultaneously, switchable via dip switches. This means:
- As Master: It can actively poll up to 247 Modbus slave devices (such as VFDs, temperature controllers, flow meters, etc.), reading register data or writing control commands.
- As Slave: It can be accessed by other Modbus masters (such as SCADA systems, HMI touchscreens, host computers), with the PLC itself acting as a Modbus slave device exposing data externally.
This dual-mode design dramatically increases system integration flexibility.
2. 9-Rate Auto-Adaptation — Maximum Compatibility
Supports 9 standard baud rates from 9.6 kbps to 12 Mbps, with automatic baud rate adaptation — the module can automatically detect the communication rate of the connected device without manual matching. This is extremely useful in complex field environments with multiple devices at mixed speeds, significantly reducing commissioning time.
3. Industrial-Grade Protection — Built Tough
- 4000V lightning protection: Suitable for outdoor installations or environments near high-power equipment with lightning risk
- 1.5A overcurrent protection + 600W surge protection: Effectively guards against power grid fluctuations and induced surges
- DC 1500V power isolation: Fully isolates the PLC side from the field device side, preventing interference from corrupting PLC programs or causing crashes
- Reverse polarity protection: Accidentally reversing the power supply during field wiring will not damage the module
- IP30 protection + aluminum reinforced housing: Dust-resistant, vibration-resistant, suitable for harsh factory environments
4. Dual Redundant Power — Zero Downtime
Supports DC 9–36V wide-range dual redundant power input. If one power source fails, the other automatically takes over without interrupting the communication link. This is critical for high-reliability continuous production processes such as chemical, metallurgical, and water treatment applications.
5. Daughterboard Installation — Zero Slot Consumption
The MVI69-MCM installs as a daughterboard directly onto the 90-70 series PLC backplane, sharing the same slot as the module it serves. No additional I/O slot is required. Installation is simple, requires no special tools, and can be done on-site for replacement and commissioning.
6. Comprehensive Status Indication and Fault Alarm
- 6 dual-color LEDs: Real-time display of power, communication, and fault status at a glance
- Relay alarm output: When a link fault or power fault occurs, the relay contact activates and can be wired to a PLC input point or alarm light for remote notification
Summary
The PROSOFT MVI69-MCM is a Modbus Master/Slave dual-mode communication module designed specifically for Allen-Bradley 90-70 series PLCs. It enables legacy 90-70 PLCs to gain powerful Modbus communication capabilities without consuming any additional I/O slots.
Its core competitive advantages are:
- ✅ Master + Slave dual mode — can actively read slave data and also be accessed by host computers; one module, two functions
- ✅ 9 baud rates + auto-adaptation — extremely convenient commissioning in multi-device, mixed-speed environments
- ✅ 4000V lightning protection + 600W surge protection + 1500V isolation — industrial-grade protection, far superior anti-interference capability compared to AB native modules
- ✅ Dual redundant power supply DC 9–36V — the top choice for high-reliability applications
- ✅ Daughterboard installation, zero slot consumption — does not waste precious I/O resources
- ✅ 6 LEDs + relay alarm output — status at a glance, rapid fault localization
- ✅ UL/CSA certified, IP30 protection — meets equipment safety requirements for food, pharmaceutical, water treatment, and other industries
If you have an AB 90-70 series PLC (SLC 500, MicroLogix, PLC-5, etc.) and need to connect it to Modbus-protocol VFDs, instruments, sensors, or host computer systems, the MVI69-MCM is one of the most cost-effective and feature-complete communication solutions available on the market today.
