Modbus RTU Communication Error

[Bharath1991]

I am getting  Error -56 intermittently. I am able to read the data from the MFC, sensor slaves but this error pops up now and then.

here is the error log.

I am using Sunrom 1430 RS 485 converter. The slaves are daisy chained with converter having a 120ohm inbuilt resistor and one 120ohm resistor connected at slave end.

I am facing this error -56  issue in all the the converters. Anyone resolved this error

26 Aug 2026_14_58_29,SubVIs.lvlib:RTU Data Unit.lvclass:Read ADU Packet.vi:5030001,SH
26 Aug 2026_14_58_33,SubVIs.lvlib:RTU Data Unit.lvclass:Read ADU Packet.vi:5030002,TH
26 Aug 2026_15_01_35,,26 Aug 2026_15_03_01,SubVIs.lvlib:RTU Data Unit.lvclass:Read ADU Packet.vi:5030003,SH
26 Aug 2026_15_03_21,SubVIs.lvlib:RTU Data Unit.lvclass:Read ADU Packet.vi:5030003,TH
26 Aug 2026_15_04_54,SubVIs.lvlib:RTU Data Unit.lvclass:Read ADU Packet.vi:5030001,R3FM2
26 Aug 2026_15_08_11,SubVIs.lvlib:RTU Data Unit.lvclass:Read ADU Packet.vi:5030002,TH
26 Aug 2026_15_09_41,SubVIs.lvlib:RTU Data Unit.lvclass:Read ADU Packet.vi:5030005,R3FM2
26 Aug 2026_15_09_46,SubVIs.lvlib:RTU Data Unit.lvclass:Read ADU Packet.vi:5030002,SH
26 Aug 2026_15_11_36,SubVIs.lvlib:RTU Data Unit.lvclass:Read ADU Packet.vi:5030001,SH
26 Aug 2026_15_12_34,SubVIs.lvlib:RTU Data Unit.lvclass:Read ADU Packet.vi:5030005,SH
26 Aug 2026_15_15_21,SubVIs.lvlib:RTU Data Unit.lvclass:Read ADU Packet.vi:5030001,SH