How To Simulate Modbus Serial Communication
There is a large selection of features and options for digital panel metres. Modbus serial communications, which frequently offer RS-485, RS-232, or USB connections, is a capability that is popular on more sophisticated digital panel metres.
Modbus is a serial communication protocol created by Modicon and released by Modicon in 1979 for use with their programmable logic controllers (PLCs). Simply put, it is a technique for exchanging data through serial lines between electrical equipment. Modbus Servers are the devices that provide the information, whereas Modbus Clients are the devices that seek the information. One Client and up to 247 Servers, each with a different Server Address from 1 to 247, make up a conventional Modbus network. The Client has the ability to upload data to the Servers.
WHAT IS MODBUS USED FOR?
Since Modbus is an open protocol, manufacturers are able to include it without needing to pay royalties for their products. It is now the most widely used method of linking industrial electrical devices and has developed into a standard communications protocol in the industry. It is extensively used by numerous producers across numerous industries. Typically, Modbus is used to transport data from instrumentation and control devices back to a primary controller or data collection system, such as a system that measures temperature and humidity and transmits the results to a computer. In supervisory control and data acquisition (SCADA) systems, Modbus is frequently used to connect a monitoring computer with a remote terminal unit (RTU). The Modbus protocol is available in serial line (Modbus RTU and Modbus ASCII) and Ethernet (Modbus TCP) variations.
MODBUS PROTOCOL SIMULATOR SOFTWARE
Modbus simulator software that runs on your personal computer enables communication with slave devices, master PLCs, or computers. The connection can be made in the form of a master or slave and can be serial or Ethernet. To read or write to an existing slave, you can use the software to execute all of the Modbus Protocol Communication function code. It is possible to set up two computers so that one runs the Master simulation programme and the other the Slave simulation software.
Setting the serial COM port’s communication parameters is the initial step in connecting to a slave. Then select the function code 01 to read the slave’s coils status starting at address 0001 and reading a length of 100 coils after inputting the slave’s address, for example, 1, in the Device ID box.
A console programme called Modbus RTU Simulator enables it to simulate any number of Modbus RTU slaves or devices for testing and debugging.
IEC 61850 PROTOCOL
IEC 61850 is an international standard that establishes communication protocols to allow for communication between various pieces of equipment found in a substation, including protective, controlling, and measuring equipment as well as (IEDs) intelligent electronic devices. This standard has had a lot of success since its first iteration in managing substation communication networks and systems. These days, it is used not only in the utility sector but also in other sectors such as wind energy and EV charging.
Chesf and UFCG are creating an IEC 61850 simulator in response to the requirement for instruments to educate engineers about the standard and assess systems. In the end, the simulator will enable configuring a distributed system protection function in a network architecture and analysing how this function reacts in systems with failures. Additionally, the simulator will allow for the testing of various network topologies, the evaluation of power system safety techniques, and the addition of new logical nodes.
The simulator being created contains the following features:
- Communication via TCP/IP.
- A collection of IEC 61850 logical nodes.
- System event registration.
It was decided to create software based on the Windows Operating System in order to achieve the aforementioned functionalities. This programme had three different sorts of components: IED, switch, and link.
IEC 61850 SERVICES
To make it simple to mimic any IED based on a SCL file (.SCD, CID, ICD, etc.) or based on a found data model that has been read from a real IED, an IED simulator is integrated into 61850 Test Suite Pro. Based on a setup from a SCL file or by finding an IED data model, the IED Simulator models an IEC 61850 server. Reporting, logging, GOOSE, tracking services, dynamic datasets, controls, and file transfer are among the supported services.