M-Bus Communication Driver

M-Bus Communication Driver is intended for data connection between Reliance's runtime software and devices communicating via the M-Bus (Meter Bus) protocol.

Communication with a PLC runs in one of the following ways:

RS-232/485 serial link
Serial link connected via Ethernet

The desired channel type can be selected in the Reliance development environment's Project Structure Manager (device connection).

Supported Reliance versions

The communication driver is supported in both Reliance 5 and Reliance 4.

Establishing a connection with the device

A connection is established by sending the SND_NKE communication packet. This packet is transmitted even if the connection is cut off. A successful connection is followed by further communication packets. If the connection is not made, the communication driver sends the SND_NKE packet repeatedly at a specified interval.

Reading data

Data is read periodically or based on a one-shot request of Reliance's runtime software. This is accomplished by sending the SND_UD2 communication packet. When reading periodically, the communication packet is sent regularly according to the update interval set for individual tags.

Detecting the loss of connection with the device

The loss of connection is detected if the communication driver doesn't receive a valid response Nx consecutively (N represents the maximum number of failed communications). This parameter can be adjusted.

Supported devices

The communication driver is able to read most devices complying with the M-Bus communication protocol standard. Besides, the communication driver has been tested with these devices:

Heat meters: Siemens UH50, Kamstrup Multical 401, Sensonic 95, Sensonic Plus, Combimeter II