WHAT IS M-BUS?

M-Bus is an abbreviation produced from the words Metering Bus. M-Bus, as the name suggests, is a standard developed for the communication of metering devices. This standard is a standard used in the measurement of measuring devices such as Electricity, Hot water and Cold water, which are generally used in homes.

The M-Bus standard was developed by Professor Dr. Horst Ziegler from the University of Paderborn.

M-Bus equipment can be powered by cable or by batteries. When M-Bus meters are interrogated by a master equipment, they transmit the information they collect to the master equipment.

The M-Bus master unit can be wired or wireless. Devices such as a handheld computer, M-Bus collector, etc. periodically connect to the meters and receive consumption information.

M-Bus equipment should not be interrogated too often, especially if it is battery powered. Since each query generates an energy consumption, the ideal query frequency is once a day.

If the cable infrastructure is ready, M-Bus meters can receive their energy over the cable. In this case, more frequent queries will not cause problems.

Wired M-Bus
In a wired M-Bus application, a pair of signal cables is installed and all M-Bus equipment is connected to the cable in parallel (BUS). The devices connected with the M-Bus collector in the center receive the energy supply through the cable. At the same time, meter information is transmitted to the collector in the center via the cable.

This system, which has a very low wiring cost due to the use of bus topology, is especially suitable for apartment buildings.

M-Bus is a protocol that performs serial communication over a pair of cables. If this structure is installed, it is possible to remotely energize the meters.

In the configuration of the M-Bus cable system, a standard telephone cable is used (JYStY N20.8 mm). The maximum recommended length for this cable is 350 meters.

Up to 250 meters can be connected in one M-Bus segment.

MBUSTOPOLOGY
In M-Bus cable communication, the communication speed can be adjusted between 300-9600 bps. By decreasing the speed and reducing the number of meters connected, the cable distance can be extended. In this case, it is recommended to adjust the cable diameter and the capacitance value should be lower than 180nf. But it is recommended that the cable distance should not exceed 1000 meters in any way.

Wireless M-Bus
There is no difference between wired M-Bus and wireless M-Bus in terms of transmitted information. Wireless M-Bus is an energy efficient protocol, which makes it possible to power the meters with batteries.

Battery life is recommended to be 10 years or more for devices using the wireless M-Bus protocol. Considering that the legal period for calibration of meters is 10 years, no additional labor will be required for battery replacement.