MODBUS RTC CRC Check

Hi,

have some issues with an Alpha ESS PV Modbus attachment.

Alpha ESS --- Modbus RTU --- IO Ninja --- RTU <-> MODBUS TCP adapter <---- oModbus Master issues FN:3.

It's fine at the oModbus Master display, but the final setup is a Modbus RTU bridge over Modbus TCP. At this setup, I get communication errors.

Any idea what's wrong?

Thanks

Henri

Hmm, the log looks strange. Both TX and RX streams are there but contain exactly identical bytes of data.

Could you please provide more info on your setup? Is it RS232 or RS485? If it's the latter, is it a 2-wire (common) or 4-wire (much less common)? Also, a wiring diagram or a picture of how you connect your USB-to-Serial adapter would help.

Also, the screenshot doesn't show the configuration of your Modbus Analyzer (is it configured as half-duplex? What is the half-duplex timeout? etc.)

This KB article could help with configuring Modbus Analyzer for half-duplex: https://ioninja.com/doc/kb/modbus_half_duplex.html