Basic Documentation

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Siemens M-bus level converter and M-bus web server A6V11157985_en--_f
Smart Infrastructure Level converter commissioning 2021-06-21
6.2 Troubleshooting the level converter
The device does not switch on. The Power LED is off.
 Using a multimeter, check whether the required operating voltage of 24 V AC or
DC is available at terminals (8) and (9).
The M-bus Error LED is on
 Check M-bus wiring. There is a bus overload due to a short circuit between the
bus cables or too many M-bus devices are connected.
The M-Bus Ready LED is switched off.
 Using a multimeter, whether M-bus power is available between terminals (6) and
(7) between DC 24 V and 42 V.
 Check the M-bus for short circuits if voltage is below that level.
The M-bus web server connected to the level converter does not recognize a
device (or not all devices).
 Make sure the wiring is correct between the M-bus web server and Terminal D
of the level converter.
 Make sure that the level converter connected via USB to the PC is not using the
bus.
 Using a multimeter, check whether the M-bus voltage on the unrecognized
devices is between 24 V and 42 V DC.
 Ensure that the communication settings on the M-bus web server or the software
are compatible with the devices (transmission rate, addressing)
Connected devices do not communicate when the level converter is used as a
repeater.
 Check whether M-bus is connected with terminal C on the level converter.
 Make sure that there is no USB cable connected to the level converter.
 Check operating and bus voltage and that the M-bus Error LED is off.
6.3 Level converter firmware WTV531..
You can use the ACT531 software to read the current firmware version on the level
converter and update as needed.
For additional information, see the ACT531 documentation.