The FX3U PLC with Ethernet Port and 2 RS485 ports you’ve described offers a comprehensive set of features for industrial automation applications. Here’s a summary of the key features and specifications:

Product Features:
- Compatibility:
- Supports USB to RS232 download cables, compatible with Xinjie or Delta download cables. Not compatible with Mitsubishi (SC09-FX) download cable.
- Power Failure Retention:
- Flash memory retains data for up to 8 years without power. Specific data retention recommendations are provided for stable operation.
- Encryption Function:
- Supports super encryption function for enhanced security. Password protection prevents unauthorized access to the program.
- Programming Port Protocol:
- Default FX protocol simplifies communication with display screens. Communication parameters for PLC and display screen are specified.
- Program Download:
- Easy program download process, including steps to create a new project, select the COM port, specify step capacity, and execute the download.
- RS232 Communication:
- Default FX programming port protocol for communication with specified parameters.
- 2 RS485 Ports:
- Independent operation (master-slave) without interference. Supports FX programming port protocol, Modbus-RTU protocol, or RS with no protocol. Specific communication parameters are provided.
- Ethernet Port Support:
- MELSOFT connection.
- MODBUS connection (MODBUS TCP/UDP server).
- SNTP connection.
- MODBUS connection (MODBUS TCP/UDP client).
- UDP supports a single connection (up to 247 slaves), while TCP supports 7 connections (up to 7 slaves).
- Default factory IP: 192.168.1.10.
- The Ethernet interface supports various functions including program upload/download, monitoring, connecting touch screens, configuration software, PLC networking, and remote control.
Note:
- Ensure consistency between the selected COM port in the software and the computer.
- The Ethernet interface occupies DA1 modification.
This PLC seems to provide a versatile and reliable solution for industrial automation, offering a range of communication options, security features, and compatibility with various peripherals. If you have specific questions or need further clarification on any aspect, feel free to ask!