I want to use M-BUS. What options do I have?

M-BUS (or Meter BUS) is quite a popular choice when interfacing with energy meters. Innon offers different options to interface your controls with M-BUS

Level converter

A "level converter" is a device that takes a 2-wires M-BUS network and converts it to a different electrical standard (such as Ethernet or RS485, making it "M-BUS IP" or "M-BUS RS485" accordingly). The protocol is basically left untouched, so a level converter allows the use of an M-BUS IP or M-BUS RS485 ready "master" to connect with a 2-wires M-BUS network, with very little configuration needed on the level converter itself.

Innon offers 2 versatile devices for this

 

The iSMA-B-MG-IP (M-BUS 2-wires to M-BUS IP)

This device allows to convert up to 6 separate 2-wires standard M-BUS branches to M-BUS over IP, allowing to connect a total of 60 M-BUS devices (distributed between the 6 available lines).

Any master device that supports M-BUS over IP (such as a Niagara 4 Jace 8000, a Niagara 4 Supervisor or MAC36NL controller through the Tridium standard driver "Mbus Tcp Ip Network") can then discover and communicate with the meters without having to do anything on the level converter (except from setting the baud rate of the M-BUS 2-wires network, which can be done using the configuration web pages of the device).

This device includes also an RS485 port that can be used to get Modbus RS485 slave devices to be accessible through the IP port, making it also a Modbus RS485 to Modbus IP level converter.

More information about this product can be found HERE

 

The Viltrus M-Bus.RS485 (M-BUS 2-wires to M-BUS RS485)

This device allows to connect a single 2-wires standard M-BUS branch to M-BUS over RS485, with a maximum of 250 devices. Note that for the device to work correctly, it is important to have a serial type connection on the 2-wires network, with no derivations, loops or stars.

Any master device that supports M-BUS over RS485 can then discover and communicate with the meters without having to run though configurations on the converter itself.

This includes Niagara 4 devices such as the Jace 8000 and MAC36NL and legacy Niagara AX devices, using the standard Tridium driver "Mbus Network".

More information about this product can be found HERE

 

Gateway

A "gateway" is a protocol converter. Like a "level converter", it transforms the 2-wires M-BUS network into something different (IP or RS485), but it has also some built in software processes transforming the protocol from M-BUS to a different standard (such as Modbus or Bacnet).

A gateway usually requires some level of configuration, as it acts as a fully geared M-BUS master device on the 2-wire side and as a slave (i.e. Modbus) on the other side (i.e. RS485).

Innon offers 1 device for this solution

 

The Viltrus M-Bus/Modbus(RS485).10 (.100 and .250 part numbers are also available for 10, 100 and 250 total maximum M-bus devices connectivity).

This device allows connecting a single 2-wires standard M-BUS branch to Modbus over RS485. Note that for the device to work correctly, it is important to have a serial type connection on the M-BUS 2-wires network, with no derivations, loops or stars.

Any master device that supports Modbus over RS485 can then access the meters data reading them from the gateway.

More information about this product can be found HERE

 

M-BUS ready controller

Some programmable controllers come with a 2-wires M-BUS port available on-board.

Innon offers a device for this

 

The iSMA-B-MAC36NL-M

iSMA-B-MAC36NL-M

This device is a programmable controller that is running Niagara 4.8 framework. The "-M" on the part number defines the variation that is provided with the onboard M-BUS 2-wires port which supports up to 20 slave devices.

The manual for the entire range of devices is available HERE.

 

The iSMA-B-AAC20-M

This device is a well established Sedona based programmable controller. The "-M" on the part number defines the variation that is provided with the onboard M-BUS 2-wires port.

The controller can be easily programmed using the manufacturer provided software called iSMA Tool (all information and downloads can be found HERE)

Comprehensive documentation with manuals for programming the device is available HERE, including a dedicated manual on the use of the Sedona module that manages the M-BUS network.

The controller could be the ideal solution to create an M-BUS to Bacnet IP, M-BUS to Bacnet MSTP or M-BUS to Modbus IP gateway.