The Allen Bradley 1771-DMC is a PLC-5 communication module designed for use within the 1771 I/O system. It provides connectivity to Allen-Bradley Data Highway (DH/DH+) networks, enabling PLC-5 processors and I/O chassis to exchange data with other controllers, operator interfaces, and supervisory systems.
This module is typically installed in PLC-5 chassis-based architectures where plant-wide communication and multi-controller coordination are required.
Technical Specifications
| Parameter | Specification |
|---|---|
| Manufacturer | Allen Bradley (Rockwell Automation) |
| Catalog Number | 1771-DMC |
| Module Type | Data Highway Communication Module |
| System Family | PLC-5 / 1771 I/O |
| Network Protocol | Data Highway / Data Highway Plus (DH/DH+) |
| Communication Speed | Up to 230.4 kbps |
| Network Topology | Token passing multi-node network |
| Max Node Capacity | Up to 64 nodes (system dependent) |
| Backplane Current Draw | ~1.0 A @ 5 V DC |
| Power Dissipation | ~5 W |
| Mounting Position | 1771 chassis slot |
| Cable Type | Twinaxial DH+/Belden 9463 (typical) |
| Operating Temperature | 0°C to 60°C |
| Storage Temperature | -40°C to 85°C |
| Weight | ~0.45 kg |
| Dimensions (L×W×H) | 118 mm × 35 mm × 87 mm |
System Role and Function
The 1771-DMC serves as a network communication bridge within PLC-5 systems, enabling integration with plant-wide industrial communication networks.
Core functions include:
- DH/DH+ network communication access
- Data exchange between multiple PLC-5 controllers
- Connection to HMI and supervisory systems
- Multi-node industrial network coordination
- Legacy plant-wide automation integration
It is commonly used in distributed industrial control architectures where centralized and remote PLC systems must communicate.
Recommended Related Modules
| Model | Function |
|---|---|
| 1785-L40B | PLC-5 Processor |
| 1771-ASB | Remote I/O Adapter |
| 1771-SN | I/O Scanner Module |
| 1771-IFE | Analog Input Module |
| 1771-OBD | Digital Output Module |
| 1771-P7 | Chassis Power Supply |
Common PLC-5 System Components
| Model | Role |
|---|---|
| 1771-A3B1 | 12-slot I/O chassis |
| 1771-A4B | 16-slot I/O chassis |
| 1771-ALX | Local I/O adapter |
| 1771-DH | Data Highway communication module (variant) |
| 2711P PanelView | HMI operator interface |
