1785-L40E | Allen-Bradley PLC-5/40E Controller EtherNet/IP 48K SRAM

The 1785-L40E is an Allen-Bradley SLC 500 series processor that provides a highly reliable and flexible platform for small to medium-sized control applications. It supports up to 40K words of memory and provides Ethernet communication for integration into larger control systems. It is a popular choice for distributed control applications and interfaces easily with a variety of I/O modules and Ethernet-based devices.

Key specifications of the 1785-L40E processor include:

• Processor Memory: 40K user memory (program and data storage).
• Input/Output Capacity: Can support up to 30,000 I/O points (depending on system configuration).
• Processor Speed: Supports fast processing with scan times typically between 10ms to 50ms (depending on the program and configuration).
• Ethernet Communication: Built-in Ethernet port for communication with Ethernet/IP and other devices over a network.
• Chassis Compatibility: Works in SLC 500 chassis along with remote I/O racks for expanded I/O capacity.
• Communication Ports: DH+ (Data Highway Plus), DF1 serial communication, and Ethernet.
• Power Supply: Typically requires 24V DC power, depending on the specific configuration of the system.
• Operating Temperature Range: Typically 0°C to 60°C (32°F to 140°F).

To connect the 1785-L40E to an Ethernet network, follow these steps:

• Ethernet Cable: Use a standard Ethernet cable to connect the Ethernet port on the 1785-L40E processor to the Ethernet switch or router.
• Assign an IP Address: Use RSLogix 500 or Studio 5000 software to assign an IP address to the 1785-L40E processor. You will need to configure network settings, such as subnet mask and gateway, if necessary.
• Configure Communication: Once the IP address is assigned, configure communication settings within the software. The Ethernet port on the 1785-L40E supports Ethernet/IP or other Ethernet-based protocols, depending on the application.
• Network Settings: Ensure all devices on the network have valid IP addresses and are on the same subnet for proper communication.

The 1785-L40E processor supports several communication protocols for integration into different network setups:

• Ethernet/IP: Supports communication with other devices that use the Ethernet/IP protocol (such as other PLCs, HMIs, and drives).
• DH+ (Data Highway Plus): Can communicate with other Allen-Bradley devices over a DH+ network, such as older SLC processors, PLC-5, or ControlLogix devices.
• DF1 (RS-232): Supports serial communication (DF1) for point-to-point connections to devices such as HMIs or other PLCs.
• Remote I/O: Can be used with remote I/O racks and supports both local and remote I/O modules to expand I/O capacity.

For all protocols, communication settings (e.g., baud rate, node address, and IP address) must be configured within RSLogix 500 or Studio 5000.

Yes, the 1785-L40E processor can be used with newer Allen-Bradley controllers and devices, although it is part of the SLC 500 series. It can communicate with other systems using Ethernet/IP, DH+, and DF1 communication protocols. However, modern PLCs such as ControlLogix and CompactLogix may require additional communication modules to integrate with older SLC 500 processors like the 1785-L40E.