Comparison between Modbus and OPC
| Feature | Modbus | OPC (OLE for Process Control) |
|---|---|---|
| Definition | Communication protocol | Communication protocol and data exchange standard |
| Protocol Type | Serial and Ethernet-based | Can use various protocols, including TCP/IP |
| Topology | Master/Slave | Client/Server and Publish/Subscribe |
| Data Types | Limited data types (e.g., integers, floats) | Extensive data types (e.g., integers, floats, strings) |
| Complexity | Simple and lightweight | More complex and feature-rich |
| Flexibility | Limited flexibility in terms of data format | Highly flexible, supports complex data structures |
| Scalability | Suitable for small to medium-scale systems | Suitable for small to large-scale systems |
| Integration | Widely used in industrial automation | Common in industrial automation, more versatile |
| Interoperability | Interoperability may be limited | Emphasizes interoperability, supports multiple platforms |
| Vendor Neutrality | Generally vendor-neutral | Allows for vendor-specific implementations |
| Security | Basic security features | OPC UA provides advanced security features |
| Standards | Open standard, but various versions exist | Open standard with defined specifications (OPC UA) |
| Popular Versions | Modbus RTU, Modbus TCP | OPC DA (Data Access), OPC HDA (Historical Data Access), OPC UA (Unified Architecture) |
| Usage | Common in simple industrial systems | Used in a wide range of industrial automation scenarios |
This table provides a high-level overview, and the choice between Modbus and OPC depends on specific project requirements and considerations.