Hi All,
Currently we are facing a issue with serial connection: We have a serial card configured with RS485 half duplex using Modbus RTU to connect to 5 slaves (daisychained). The end has 120ohm termination resistor. The total cable length of the segment is less than 50m. Baudrate is set to 38400. The slaves are WAGO 750-315/300. When all devices are connected, only the first device is communicating. The rest are shown are Not Communicating on Diagnostics.When we unplug the 4th device on the segment, the first 3 devices on the segment communicates well. We can never get the 5th device to communicate. During FAT, all devices were communicating..The timeout is set at 1second but i tried 3 seconds too. No difference. Also tried increasing retry count to 3 but no improvement.The Wago fieldbus connectors have resistor switches on it but does not make a difference ON or OFF.We replace the Wago fieldbus connector on the 4th device but did not improve.Any clue whats happening?
Thank you.
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