What is Wired Automation? RS485, Modbus and Integration
Wired automation; It is a structure where sensors, control devices and other equipment exchange information via physical cable connections. The electrical properties of the connection and the communication protocol that defines the meaning of the data are separate issues. Both need to be examined for compatibility.
Are RS485 and Modbus the same thing?
RS485 defines the electrical communication interface, and Modbus defines the application protocol used to exchange data between devices. Therefore, just because a device is connected to RS485 does not mean that it will work directly with another Modbus device. The protocol format, communication settings and the data map provided by the device should also be evaluated. Modbus publishes separate documentation for serial line and TCP/IP implementations.
Why is a data map necessary?
The software cannot automatically know whether the number in a recording address is temperature, counter value or status information. The address, data type, scale, unit and reading format must be verified from the manufacturer's documentation. For example, seeing 250 on the screen cannot be interpreted as 250 degrees without knowing the scale of the device. Records with writing authority should be handled separately; Unnecessary control functions should not be opened in projects that only require monitoring.
Wired or wireless?
If the cable route is possible, cable structure can be evaluated; Wireless options can be examined in areas where access is difficult. The decision isn't based solely on ease of installation. Data frequency, latency expectation, maintenance, power supply and existing infrastructure are compared together. In a hybrid project, data collected from local wired devices can be transferred to the central software over another network.
What documents do you request before the project?
Device models, connection diagrams, protocol documents, data maps and access authorizations should be prepared. Installation and testing are carried out by qualified personnel according to the manufacturer's instructions for the relevant hardware. The values read during delivery should be compared with the field device, the visibility of connection loss and the up-to-dateness of the addressing list should be checked. This guide is not a connection or electrical installation instruction.
Technical questions and answers
Does every device with RS485 input support Modbus?
No. Electrical interface and protocol support are different features; The device documentation should be examined.
Are Modbus RTU and Modbus TCP the same connection?
It is not the same connection format. Network, device and, if necessary, gateway coverage is evaluated on an application-by-application basis.
Should Modbus data be exposed directly to the internet?
Connection design should be accompanied by access limits and protection needs. Unnecessary external access should not be considered a project requirement.
Can devices of different brands work together?
Integration can be evaluated if there is a compatible interface, protocol and data map; Brand difference or being the same brand alone is not enough.