Basic Documentation

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Siemens M-bus level converter and M-bus web server A6V11157985_en--_f

Smart Infrastructure 2021-06-21

4.4.3 RF converter

Select a power supply AC 100...240 V as described in the technical data.

4.4.3.1 Locating RF converters

The RF converter receives data from one or more wireless devices within a radio

system per EN13757-4. The RF converter forwards the received data to the web

server.

You can power the RF converter over a USB connection using an external battery

(>= 5000mAh; @5V; >= 1.5A) to help in the search for the optimum location. The

RF converter remains mobile during the scan and can be moved to the location

with the best signal reception.

A flashing blue LED indicates that the location is unfavorable and there is no

connection to the web server.

Once a favorable location has been found and a connection set up from the device

to the web server via the RF converter, the blue LED stops flashing and the search

for wireless devices begins.

The green LEDs only light up once a connection to the web server has been

established. The number of green LEDs that are illuminated indicates the signal

strength. When all four LEDs light up, you have a strong signal. The blue LED

remains permanently illuminated.

The minimum distance between RF converters is 5 m. The RF converter must be

at least 20 cm from the ceiling and the wall where it is mounted.

4.5 M-bus

4.5.1 M-bus addressing

M-bus uses two addressing types to recognize and communicate with wired M-bus

devices:

 Primary addressing:

Up to 250 primary addresses can be assigned per line to an M-bus system. The

primary address is normally assigned during M-bus device commissioning.

 Secondary addressing:

Secondary addressing consists of 8 digits and permits the assignment of any

number. In the default setting, the secondary address for a M-bus device

matches the serial number issued by the device manufacturer. The assignment

prevents address conflicts on the M-bus and permits addressing of more than

500 M-bus devices on a system.

4.5.2 Sizing the wired M-bus system

Allowable cable types:

 Shielded telephone cable 0.5 mm

(4 x 0.8 mm)

 NYM cable (1.5 mm

)

 Maximum capacitive cable load of 152 nF/km

Note