The Desigo building automation and control system offers multiple options to integrate M-bus devices. M-bus devices and their data points are mapped to BACnet objects. In this way, M-bus meter data points can be made available to other controls and BACnet clients. The system offers different ways to integrate M-bus devices for online and offline engineering.

Onboard M-bus interface

 

Connect up to 4 M-bus devices to your automation station directly. The onboard interface is compliant to EN 13757-2. Baud rates of up to 9600 bit/s are supported.

The following system controller and automation stations can be used as M-bus manager to integrate M-bus devices directly:

  • PXC5.E003
  • PXC5.E24
  • PXC7.E400

Onboard M-bus interface in combination with M-bus repeater

 

Connect up to 60 M-bus devices to your automation station via an M-bus repeater. The onboard interface is compliant to EN 13757-2. Baud rates of up to 9600 bit/s are supported.

The following system controller and automation stations can be used as M-bus manager to integrate M-bus meters connected via an M-bus repeater:

  • PXC5.E003
  • PXC5.E24
  • PXC7.E400

M-bus repeater used in the configuration example: Siemens, WTV531-GA5060, A6V10844290.

 

 

Connect up to 250 M-bus devices to your automation station via an M-bus repeater. The onboard interface is compliant to EN 13757-2. Baud rates of up to 9600 bit/s are supported.

The following system controller and automation stations can be used as M-bus manager to integrate M-bus meters connected via an M-bus repeater:

  • PXC5.E003
  • PXC5.E24
  • PXC7.E400

M-bus repeater used in the configuration example: Siemens, WTX631-GA0090, A6V11742346.

M-bus devices integration via RS485 level converter

 

Connect up to 250 M-bus devices to your automation station via an RS485 level converter. The highest available baud rate depends on the limitations of the level converter and the connected M-bus devices. The RS485 interface for M-bus supports baud rates of up to 38400 bit/s.

The following system controller and automation stations can be used as M-bus manager to integrate M-bus meters connected via an M-bus repeater:

  • PXC4.E16-2
  • PXC4.M16-2
  • PXC5.E003
  • PXC5.E24
  • PXC7.E400

Configuration examples for different RS485 level converters:

STV Electronic, MPW-2

2 M-bus devices

STV Electronic, MPW-6

6 M-bus devices

Relay GmbH, PW60

60 M-bus devices

Siemens, WTX631-GA0090

250 M-bus devices

 

To be considered for all M-bus configurations listed above:

The ABT Site engineering tool checks the number of data points and not the number of M-bus devices (for details, refer to the system limitations in this document "PXC4-2, PXC5, and PXC7 automation stations"). The maximal number of devices per network depends on the individual load of each device and the given power supply by the M-bus manager or level converter. The maximum number of M-bus devices is usually defined as "simple M-bus loads à 1.5 mA".

For further details, refer to the expert documentation for M-bus (Meter-Bus) A6V16039082 or see the M-bus website.