1771-IK Ser A (PU)

Allen Bradley Bulletin 1771 | Encoder Counter Module

Allen Bradley Bulletin 1771 | 2-Channel 5VDC (TTL) Encoder/Counter Module, supports high-speed counting and position feedback, Series A"

The Allen-Bradley 1771-IK is a high-speed specialty I/O module designed for the 1771 Universal I/O platform. It is engineered to provide precise position and pulse-counting capabilities for PLC-5 systems by interfacing with 5VDC encoders and high-speed pulse-generating devices. It is a critical component for applications involving motion control, conveyor synchronization, and high-speed material handling.

This Series A module features two independent channels capable of processing 5VDC (TTL-level) signals. It supports a variety of counting modes, including quadrature encoder feedback (Phase A, Phase B, and Z-index) and simple up/down pulse counting. To ensure high accuracy in noisy industrial settings, the module provides robust optical isolation between the high-speed field inputs and the PLC backplane, protecting the control logic from electrical transients.

Physical termination is handled via the standard 1771-WH field wiring arm, allowing for rapid module replacement without disconnecting individual field wires. The module includes front-panel diagnostic LEDs that indicate the status of each channel and the presence of input pulses, facilitating real-time monitoring and troubleshooting. It is capable of handling pulse frequencies up to 50 kHz, making it suitable for most standard industrial sensing applications.

Built for heavy-duty industrial use, the 1771-IK operates reliably between 0–60°C (32–140°F). It draws 250mA of current at 5VDC from the chassis backplane. The module is built to withstand industrial-grade shock and vibration and is UL listed, CSA certified, and CE compliant, ensuring it meets the safety and reliability requirements for global industrial automation projects.

Key Specifications:

- Function: High-Speed Encoder / Counter
- Channels: 2 Independent Channels
- Input Voltage: 5VDC (TTL Compatible)
- Max Frequency: 50 kHz
- Backplane Current: 250mA @ 5VDC
- Wiring Arm: 1771-WH
- Platform: 1771 Universal I/O (PLC-5)
- Series: A