1785-KE | Allen-Bradley PLC 5 Data Highway Plus Communication Module

Description

The Allen-Bradley 1785-KE is a single-slot PLC 5 communication interface module designed for Data Highway Plus networks and RS-232-C connections. It mounts in 1771 I/O chassis and supports PLC2, PLC3, PLC4, and PLC5 controllers. The module provides one DH+ port and one RS-232-C port, with DH+ speeds up to 57,600 bps and switch-selectable RS-232-C rates from 110 to 19,200 bps. Power is supplied via the backplane at 1.2 A (5V DC). The unit features conformal coating for harsh environments, LED status indicators per channel, and supports up to four modules per system. Typical signal delays are 29–30 ms for AC/DC. Compatible accessories include 1770-CD DH+ cables and 1771-WN wiring arms.

Technical Specifications

• Manufacturer: Allen-Bradley

• Model Number: 1785-KE

• Product Line: PLC 5

• Product Type: Communication Interface Module

• Weight: 1.81 lbs (0.82 kg)

• Mounting: 1771 I/O chassis

• Compatible Controllers: PLC2, PLC3, PLC4, PLC5

• Built-in Ports: 1 DH+, 1 RS-232-C

• Module Width: Single Slot

• DH+ Transmission Speed: up to 57,600 bps

• RS-232-C Transmission Speed: 110–19,200 bps

• Backplane Current Draw: 1.2 A at 5 V DC

• Operating Temperature: 0–60 °C

• Storage Temperature: -40–85 °C

• Relative Humidity: 5–95% non-condensing

• Max Modules Per System: 4

• LED Indicators: 1 per channel for diagnostics/status

• Coating: Conformal coat

• Required External Power: None

• Typical AC Signal Delay: 29 ±8 ms

• Typical DC Signal Delay: 30 ±7 ms

• Compatible Accessories: 1770-CD DH+ cable, 1771-WN wiring arm

Application Scenarios

Ideal for industrial automation networks, the 1785-KE enables reliable DH+ and serial communication between PLC controllers, supporting data exchange, monitoring, and control in multi-node systems.

Comparison with Similar Models

• 1785-KE: Single-slot DH+ and RS-232-C interface, supports up to four modules per system.

• 1785-KC: Higher-speed DH+ and expanded serial capabilities.

• 1785-KD: Supports additional redundancy and diagnostic features.

FAQs

Q1: Which PLC controllers are compatible with 1785-KE?
A1: It supports PLC2, PLC3, PLC4, and PLC5 series controllers.

Q2: How many DH+ modules can a system include?
A2: Up to four 1785-KE modules can be installed per system.

Q3: Does it require external power?
A3: No, the module is powered entirely through the 1771 chassis backplane.