Modbus Protocol for .NET | TCP

The Modbus TCP protocol implementation.

Example

A simple example which reads the voltage between L1 and N of a Janitza device.

string host = "modbus-device.internal";
int port = 502;

using var client = new ModbusTcpClient(host, port);
await client.ConnectAsync(CancellationToken.None);

byte unitId = 5;
ushort startAddress = 19000;
ushort count = 2;

var registers = await client.ReadHoldingRegistersAsync(unitId, startAddress, count);
float voltage = registers.GetSingle();

Console.WriteLine($"The voltage of device #{unitId} between L1 and N is: {voltage:N2}V");

If you want to use the RTU over TCP protocol instead, you can do this on initialization:

// [...]

using var client = new ModbusTcpClient(host, port)
{
	Protocol = new RtuOverTcpProtocol();
};

// [...]

Sources

• Protocol Specification: v1.1b3
• Modbus TCP/IP: v1.0b

Published under MIT License (see tl;drLegal)