Solvimus MBUS-M13 Series, Руководство пользователя

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MBUS-M13 - User manual
Table 4 –
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Terminal Description -S -G -M
TP_PGND M-Bus-side power supply, Ground (0 VDC) GND nc nc
TP_PWR M-Bus-side power supply (24 VDC) 24 VDC nc nc
TP_ANT do not connect nc nc nc
TP_BUS- M-Bus, low-side M-Bus- M-Bus- M-Bus
M-Bus, high-side M-Bus+ M-Bus+ M-Bus+
Table 4: Function of the terminals for the pin headers
2.4.2 Connector X1
Pin Name Description -S -G -M
1 MB+ M-Bus, high-side nc nc M-Bus+
2 MB- M-Bus, low-side nc nc M-Bus
3 VCC power supply 3.3 VDC nc VDD VDD
4 24V power supply 24 VDC nc 24 VDC 24 VDC
5 GND power supply, Ground nc GND GND
6 #COL collision interrupt (see Section 2.6.2) #COL #COL #COL
7 WRX do not connect nc nc nc
8 WTX do not connect nc nc nc
9 RX UART Receiver (to RX) nc RX RX
10 TX UART Transmitter (from TX) nc TX TX
Table 5: Pin assignment of the connector X1
2.4.3 Signalling on the M-Bus
The M-Bus is a single master multiple slave bus. Therefore, a single bus master controls the bus and the data
traffic on the bus. Several slaves, i.e. meters, can be connected to the bus.
A second physical master is not allowed on the M-Bus.
On a physical level, the M-Bus uses voltage and current modulation to transmit data. The master transmits
telegrams by modulating the bus voltage, the slave transmits telegrams by modulating the current through
the bus. This is shown schematically in the following figure (values of current and voltage may deviate):
Figure 3: Signalling on the M-Bus
The M-Bus follows the principle of request-response, i.e. the master initiates the communication by a re-
quest/command which is then answered/confirmed by the slave. Spontaneous data transmission on the part
of the slaves is not allowed.
Certain terms are used in the M-Bus standard. The basics of communication are taken from IEC 60870-5-101.
Key terms are explained in the table below:
Term Description
ACK ACKnowledge, confirmation of a command, transmitted over the M-Bus as a single char-
acter telegram with content 0xE5.
Application reset Reset of the application layer, command to reset the meter to the default state and to
reset the meter for consecutive telegrams (multipaging).
Broadcast Broadcast, command or request is sent to all slaves, special addresses 0xFE and 0xFF are
used.
C-field Command field, code that indicates the direction in which a telegram is exchanged and the
meaning of the telegram.
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Frank Richter, 6 December 2022
© solvimus GmbH Version: 1.09
Released
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UG_EN_MBUS-M13.pdf