ModbusRTU Communication between UPS and Beckhoff IPC

[jenako]

For the purposes of a project we want to display the UPS status (Phoenix Contact UPS-QUINT, part number: 2320267) in the program run in the IPC. The machine will work remotely so it is important to monitor battery charge. The Phoenix Contact UPS uses Modbus RTU (serial RS232), and can communicate with the EL6001 RS232 series terminal (Beckhoff) with the IFS-RS232 -datacable (Phoenix contact). I am attaching the documentation for the MODBUS communication for the QUINT UPS. My problem is that I have not any experience with serial communication and although I searched the Beckhoff website I could not find useful examples or relevant documentation of how to read the UPS battery's state charge. Any help or code example would be much appreciated, thank you in advance for your consideration.