M-Bus gateway failures

The M-Bus gateway only recognizes a meter with the secondary address, which is usually also listed on the acceptance report.

The combined meters are then displayed separately on the portal. For this application, smart-me uses its own numbering logic.

All meters that are not relevant for billing can be deactivated to save license costs. Deleting them is not expedient, as the meter will appear again and again.

If a meter contains more than 1 meter, these are numbered as follows:

• Main meter = secondary address of the M-Bus gateway list (e.g. 71440145)

• Additional meters = secondary address of the main meter, the first number is deleted (e.g. 7) and a number is incremented at the end (e.g. 14401451,14401452).

• Sub-counter = These contain the last four digits of the main counter (e.g. 0145) and a four-digit enumeration number at the end (e.g. 01450001)

How to prevent the detection of new devices

• Select M-Bus Gateway.

• Select the M-Bus Gateway gear wheel (top right). Note: Do not select the upper gear wheel, which is used to configure the meters, but the lower one.

• Edit

• Check the box “Don't allow to add additional meters”.

• Save

What is the effect of this option?

• Activating the “Don't allow to add additional meters” option prevents devices that are not yet available in the cloud from being saved. 

What needs to be considered?

• If new devices are added, this option must be deactivated again before the search.

When is this option recommended?

• If M-Bus devices keep popping up in the portal that do not actually exist.

• For preventive reasons :-)

In which circumstances can this occur?

• In the event of errors in data transmission. This occurs more frequently if the M-Bus cable is excessively long and therefore the quality of the data transmission decreases, or if the cable is poorly shielded or exposed to external interference.

Technical explanation

• The standardized M-Bus protocol has only 1 byte for the checksum. The checksum is intended to detect certain errors in the data transmission. Unfortunately, 1 byte is not much and can always lead to a corrupted data packet being regarded as valid and correct. In some installations where M-Bus Gateways are used, this repeatedly leads to corrupt data packets being classified as valid and correct and these are then recognized and added as a new M-Bus device in our cloud. The account then drops from Professional to Basic, as the license coverage is no longer sufficient.