Siemens M-bus Level Converter/Repeater 250 User manual

A6V11742346_en
--_a Smart I
nfrastructure
2019-10-01
Meters and Energy Cost Allocation
M
-bus Level Converter/Repeater 250
WTX631
-GA0090
The level converter/repeater WTX631-GA0090 is the interface between M-bus
device and a read system. It consists of a level converter and
the associated
power supply.
●
The level converter and associated power supply form a unit: No addition
transformer or auxiliary power required
●
Connect up to 250 M-bus devices (max. 250 simply M-bus loads)
●
Can be used with the M-bus web server WTV676.., PXC devices, other M-bus
read / configuration systems
●
Up to 6 level converters connected in parallel on one M-bus network
●
Up to 6 level converters (max. 5 level converters as repeater,
serial) connected on
one M-bus network
●
Local data reading of M-bus devices via RS-232 or RS-485 interface
●
Remote reading of M-bus devices via M-bus web server WTV676.. (Cloud)

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Use
The level converter is the communications interface to read up to 250 M-bus devices (simple
M-bus loads).
The data is read via a M-bus web server WTV676, a PXC device, or via other M-bus
read/configuration systems.
Multiple level converters can be connected in parallel on one M-bus network. When
connected to a M-bus web server, up to six level converters can be connected in parallel. Up
to six level converters/repeaters can be serially connected (max. five level converters as
repeater).
The power supply can be used to power the M-bus web server (output "Vout 24Vdc").
(6) (6) (6) (6) (7) (7) (7) (7) (8) (9)
M-Bus MASTER Vin
LC
(5) (3) (4) (3) (4)
ABC
RS-485
V
A V B
(5)
(1) (2)
DE F RS-232
Run
TX M-Bus
RX M-Bus
Short Circuit
Overload
Power
WTX631-GA0090
LEVEL CONVERTER
(3) (4) (5) (6)
Vout
24Vdc
(4)
V
+ V-
(5)
(1) (2)
Power
230Vac
Vout
LC
V A
V B
WTX631-GA0090
POWER SUPPLY
The level converter/repeater can be connected and used as follows:
●As M-bus slave (repeater) on a M-bus web server WTV676.. .
●As M-bus level converter via interfaces RS-232 or RS-485 to a PXC device or a laptop.
Up to 250 M-bus devices can be connected to the M-bus master (250 simple M-bus loads).
The input for the M-bus slave and the RS-232 interface are galvanically isolated.
Interface RS-485 and the output for the M-bus master are not galvanically isolated.
The output on the M-bus master is protected against short circuits.
You can use the level converter at your own risk as an interface as well to suitable software
and devices by third-party manufacturers.

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Functions
Operating modes
The power supply can be employed as follows:
●To power the level converter
(6) (6) (6) (6) (7) (7) (7) (7) (8) (9)
M-Bus MASTER Vin
LC
(5) (3) (4) (3) (4)
A B C
RS-485
V
A V
B
(5)
(1) (2)
D E F
RS-232
Run
TX M-Bus
RX M-Bus
Short Circuit
Overload
Power
(3) (4) (5) (6)
V
out
24Vdc
(4)
V
+ V-
(5)
(1) (2)
Power
230Vac
Vout
LC
V
A
V B
WTX631-GA0090
LEVEL CONVERTER WTX631-GA0090
POWER SUPPLY
(8) (9)
LC
VB
(3) (4)
LC
VB
12
1 Level converter/repeater 2 Power supply
●To power the M-bus web server WTV676.. (DC 24 V).
A
(6) (6) (6) (6) (7) (7) (7) (7) (8) (9)
M-Bus MASTER Vin
LC
(5) (3) (4) (3) (4)
A B C
RS-485
VAVB
(5)
(1) (2)
D E F RS-232
Run
TX M-Bus
RX M-Bus
Short Circuit
Overload
Power
(3) (4) (5) (6)
Vout
24Vdc
(4)
V+V-
(5)
(1) (2)
Power
230Vac
Vout
LC
VAVB
WTX631-GA0090
LEVEL CONVERTER WTX631-GA0090
POWER SUPPLY
B
12
A Web server WTV676.. 1 Connection web server WTV676.. with power
supply WTX631
B Level converter/repeater
WTX631 2 Connection level converter/repeater with power supply
The level converter can be used in various ways.

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Level converter as slave, reading over the M-bus web server
The level converter is connected as a slave to a M-bus web server WTV676.. to extend the
M-bus network. Up to six level converters can be connected in parallel. A max. of six level
converters (max. five repeaters) can be connected serially to overcome large distances. The
data is read via the M-bus web server.
A maximum of 250 M-bus devices can be read via M-bus web server.
A M-bus web server
(M-bus master) 1 M-bus slave, connected in parallel (max. 6 level converters)
B Level converter 2 RS-232, serially connected (1 level converter and 5
repeaters)
C M-bus wireless devices
D Level converter as repeater
Additional information on web server WTV676.. is available in the user guide
"M-bus web server WTV676-HB6035, M-bus level converter WTX631-GA0090, M-bus level
converter WTV531-GA5060, RF converter WTX660-E05060", document A6V11157985. See
Section "Product documentation [➙12]".

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Level converter as master for reading data over the RS-232 or RS-485 interface
The level converter can be connected as master via the RS-232 or RS-485 interface to a
PXC device or a PC to read device data.
A Level converter (RS232 or RS485 interface)
B PC or M-bus devices
NOTICE
The level converter WTX631-GA0090 does not have a mini USB interface to locally read
the data. The device data cannot be read locally with the ACT531 software.
The TX Open module integrates M-bus devices via a RS-232 or RS-485 interface to the
Desigo CC building management platform.
Additional information on the Desigo CC management platform is available in the
engineering guide 'Desigo TM TX Open, TX M-bus', document CM110572. See Section
"Product documentation [➙12]".

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Level converter as standalone device with up to 250 connected M-bus devices
The level converter can be used as the master on one M-bus network with up to 250 M-bus
devices.

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Displays
The level converter has six LEDs on the front side for indicating the operating state.
Run
TX M-Bus
RX M-Bus
Short Circuit
Overload
Power
Run…
The (green) LED indicates the operational state of the device.
●Blinking at 1 Hz (slow) -> Device functions are being set up. No communication.
●Blinking at 0 Hz (fast) -> Device update pending.
●On -> The device is operational.
TX M-bus
The (green) LED indicates the transmission state on the M-bus network (terminals 9 and 10).
●On -> Data is transmitting.
●Off -> No data is transmitting.
RX M-bus
The (orange) LED indicates the receive state of data on the M-bus network (terminals 6 and
7).
●On -> Data is being received.
●Off -> No data is being received.
Short circuit
The (red) LED indicates a short circuit on the bus, very high traffic, or a collision.
Overload
The (orange) LED indicates a bus overload that may prevent correct operation.
●On -> Bus overload that may prevent correct operation.
●Off -> No bus overload recognized.
Power
The (green) LED indicates the state of the level converter power supply.
●On -> The device power supply is correct.
●Off -> Device power is not correct or unavailable.

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Technical design
Topology
The M-bus permits various network topologies. The devices can be connected to the level
converter in a line, bus, star, or tree topology, or a combination thereof.
Ring topology is not permitted.
Bus cable polarity is not relevant, simplifying installation.
Line topology
Bus topology
Star topology

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Tree topology
Combination of topologies
Ring topology

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M-bus
Address
M-bus uses two types of addresses to recognize devices:
●Primary addressing: Up to 250 primary addresses can be assigned to a M-bus system.
The primary address is normally assigned during device commissioning. Pure primary
addressing is not possible if more than 250 devices are read on the M-bus network.
●Secondary addressing: Secondary addressing consists of 8 bytes and permits the
assignment of any number. In the default setting, the secondary address for a device
normally matches the serial number issued by the device manufacturer. The assignment
prevents address conflicts on the bus.
Bus expansion
Plant type Maximum
distance Total cable length Cable cross section Number of devices (slaves) Max.
transmission
rate
Small residential
buildings 350 m 1000 m 0.8 mm2250 9600 baud
Large residential
buildings 350 m 4000 m 0.8 mm2250 2400 baud
64 9600 baud
Small
developments 1000 m 4000 m 0.8 mm264 2400 baud
Large
developments …3000 m* 5000 m 1.5 mm264 2400 baud
Direct vicinity …5000 m* 7000 m 1.5 mm216 300 baud
Point-to-point
connection …10000 m* 10000 m 1.5 mm21 300 baud
*Shielded cabling required at a distance in excess of 1000 m (see EN13757-2 appendix E).
Signal specification
M-bus Condition Minimum Typical Maximum Measuring unit
Number simple
M-bus loads per
segment
WTX631-
GA0090 0 - 250 -
Transmission
rate CSegment ≤ 382 nF 300 2400 9600 baud
Bus power
(Master) WTX631- GA0090 30 39 42 R
Bus current
(master) WTX631- GA0090 0 - 375 mA