akYtec News

The RS485 interface has gained quite a common application in Fieldbus networks. This is a high-speed and interference-resistant serial interface which makes it possible to create networks connecting many devices into a common bus.

By optimizing the electronic circuit, significant improvements have been achieved in our digital display ITP11. In particular, the voltage drop has been reduced to max. 4 V. This allows the ITP11 to be powered directly from the active output of a PLC or other device. In addition, the ITP11 has also been given an alarm function that activates the blinking of the display when the signal is outside the specified range.

Interface a shared transition point between two or more functional units (device, PC, etc.) defined by common characteristics of physical interconnections, signal characteristics, and functional characteristics of interconnection circuits.

Protocol is a standardized set of rules for data transmission over a communication interface.

Strict cost requirements and a huge variety of automation scenarios mean that it is not possible to develop a universal programmable logic controller (PLC). For this reason, the following challenges can also arise down the road even if a well-suited controller has been selected:

• - Insufficient PLC resources, e.g. a low number of inputs and/or outputs
• - Issues with compatibility with other devices in the network (interface, protocol, etc.)
• - Large distances from the PLC to field devices.

To solve this and similar problems, remote I/O-modules have been developed. These modules are used to set up decentralized systems, to control industrial objects and processes. The expansion modules can complement such systems, with multiple inputs or outputs, thus ensuring more functionality and flexibility of the systems. Among many decentralized systems, the single-master systems based on the RS485 serial interface and Modbus protocol have become the most established in industrial automation. That is why akYtec I/O modules have the appropriate interfaces and protocols.

When developing an automation system using CODESYS, one often faces the task of implementing a fieldbus system. For example, there is a need to carry out climate control in a vegetable storage facility based on the akYtec SPK207 control panel. Since the SPK207 does not have its own inputs and outputs, expansion modules must be used. There is the possibility to connect the akYtec Mx100 I/O modules via the RS485 interface as well as any other modules via the ethernet interface to this control panel. This article details the steps required to properly configure the SPK207 for data exchange via Modbus protocol in CODESYS v3.5 SP3 Patch 5.

Configuring the MSD200 data logger for data exchange via Modbus with the MV110-8A Input Module from akYtec over the RS485 interface, and data logging from one of the 4-20 mA inputs