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Modbus Error Log
#1
Hello
I have errors in the Modbus error Logs but the slave devices are working, I can read and write.
errors are: 
- read failed: operation timed out
- read failed: response not from requested slave
I got a lot of these errors in the error log

is it ok to see these errors? 

Note that I have slave devices on Modbus TCP with no errors
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#2
It means that there are some minor issues with the RS485 communication.
Some things to consider:
1. Connect GND between all Modbus devices (read this: https://store.chipkin.com/articles/rs485...wire-rs485)
2. Install 120 ohm terminator resistor on both ends of the RS485 bus
3. Topology: daisy-chain connection is recommended. Short stubs are OK as well, never use star topology
4. Try using a lower baud rate if devices allow this
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#3
(19.04.2021, 06:25)admin Wrote: It means that there are some minor issues with the RS485 communication.
Some things to consider:
1. Connect GND between all Modbus devices (read this: https://store.chipkin.com/articles/rs485...wire-rs485)
2. Install 120 ohm terminator resistor on both ends of the RS485 bus
3. Topology: daisy-chain connection is recommended. Short stubs are OK as well, never use star topology
4. Try using a lower baud rate if devices allow this

Thank You, Admin
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