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Modbus RS485 using USB Dongle - Printable Version

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Modbus RS485 using USB Dongle - jmir - 13.01.2025

Hi,

I'm using a USB Dongle as modbus RTU3, it's working fine but when I unplug the dongle and connect again the port name switches form " /dev/ttyUSB0" to "/dev/ttyUSB1"...
Is there any way to fix the port name? When it happens the only way to make it working again is rebooting LM...


RE: Modbus RS485 using USB Dongle - jmir - 15.01.2025

(13.01.2025, 09:23)jmir Wrote: Hi,

I'm using a USB Dongle as modbus RTU3, it's working fine but when I unplug the dongle and connect again the port name switches form " /dev/ttyUSB0" to "/dev/ttyUSB1"...
Is there any way to fix the port name? When it happens the only way to make it working again is rebooting LM...

Is there any way to solve it?


RE: Modbus RS485 using USB Dongle - admin - 15.01.2025

USB is not a reliable solution. It can disconnect randomly due to electromagnetic noise presence. If you need more ports consider using LM5 DR. Alternatively you can use a third-party Modbus RTU-TCP gateway.


RE: Modbus RS485 using USB Dongle - jmir - 15.01.2025

(5 hours ago)admin Wrote: USB is not a reliable solution. It can disconnect randomly due to electromagnetic noise presence. If you need more ports consider using LM5 DR. Alternatively you can use a third-party Modbus RTU-TCP gateway.

Ok thanks!