The Allen-Bradley 1785-L40E is a powerful PLC-5/40E controller with 48K words of user memory. This module supports 2048 total I/O points in any mix. It handles 2048 inputs plus 2048 outputs in complementary mode. Engineers use it for medium to large automation tasks. The controller features rugged environmental tolerances and multiple communication ports.
Product Procurement & Buyer Guide
Procurement managers must verify chassis compatibility before purchase. The 1785-L40E fits 1771-A1B, -A2B, -A3B, -A3B1, and -A4B chassis. Use power supplies like 1771-P4S, -P6S, -P4S1, or -P6S1. The module draws 3.3 A from the backplane. It dissipates 17.3 W of power. Install optional backup memory such as 1785-ME64 or 1785-ME32. The internal battery is model 1770-XYC.
This controller offers three I/O addressing modes. Use 2-slot mode for 8-point and 16-point modules. Use 1-slot mode for 8-point, 16-point, and 32-point modules. The half-slot mode supports any mix of 8, 16, and 32-point modules. This flexibility reduces wiring costs and simplifies system design.
The 1785-L40E connects to networks through four embedded ports. It has one Ethernet/IP port using TCP/IP protocol. It provides two DH+/Remote I/O ports for scanner or adapter roles. One serial port supports RS-232-C, 422-A, and 423-A standards. These ports enable communication with HMIs, other PLC-5s, and remote I/O racks.
Expert Technical Evaluation & Performance Review
The 1785-L40E delivers fast I/O scan times for high-speed applications. The remote I/O rack scans at 10 ms at 57.6 kbps. At 115.2 kbps, it scans in 7 ms. At 230.4 kbps, it achieves 3 ms per rack. The extended-local adapter supports a selectable scan time of 0.5 ms. These speeds suit time-critical manufacturing lines.
The controller operates reliably in harsh environments. It functions from 0 to 60 °C without de-rating. It withstands 5 to 95% non-condensing humidity. The module tolerates 30G operational shock and 1G vibration at 10 to 500 Hz. Certifications include CSA, C-TICK, CE, and UL. The internal clock stays within ±5 minutes per month accuracy.
System capacity supports up to 16 I/O racks (0 to 15). You can link up to 61 I/O chassis total. One local chassis and 60 remote chassis are possible. Each link handles a maximum of 32 I/O modules. The controller addresses 2048 analog I/O points as well. This scalability meets growing plant requirements.
The 1785-L40E uses battery-backed static RAM for program retention. You can also use EEPROM backup via 1785-ME16, -ME32, -ME64, or -M100 modules. Programming languages include ladder logic, structured text, and sequential function charts. It supports PID algorithms for closed-loop control. This versatility makes it ideal for discrete and process applications.
Logistics & Standard Packaging Details
Express shipping is available via FedEx, UPS, and DHL. Orders ship from our warehouse within one business day. Contact our sales team for bulk pricing and lead times.
