Allen-Bradley 1771-QB | Industrial PLC Motion Control Module

Overview

The Allen-Bradley 1771-QB is a Linear Positioning Module designed for the 1771 PLC platform. It integrates machine motion control and provides the PLC with hydraulic performance capability. The module supports two independent axes and advanced control algorithms, including PID and Feed-forward control.

Technical Specifications

• Model Number: 1771-QB

• Module Type: Linear Positioning Module

• Brand: Allen-Bradley

• Series: 1771

• Module Location: 1771 Universal I/O chassis

• Update Period: 2 ms per axis

• Analog Output Resolution: 12-bit

• Analog Outputs: ±10V DC up to 10 mA, ±20 mA up to 600Ω, ±50 mA up to 240Ω, ±100 mA up to 240Ω

• Discrete Outputs: Single-ended sourcing, 100 mA maximum, logic 0: 0V, logic 1: user voltage

• Discrete Inputs: 8 mA/input at 12 V DC, 16 mA/input at 24 V DC, logic thresholds 0–4 V DC (0) and 10–30 V DC (1)

• Transducer Compatibility: MTS Temposonics, Balluff BTL, Norstat GYRG linear displacement transducers

• Maximum Transducer Length: 180 inches (4.572 meters) with resolution ±0.002 inches

• Sampling Period: 2 ms

• Terminal Block: 40 Terminal 1771-WN

• Conductor Wire Size: Max 14 AWG, 3/64” insulation

• Auxiliary Outputs: Servo valve, digital source, analog ±10V DC/ ±20–100 mA

• Slots: 1

• Fuse Rating: 3A, 250V, normal-blow

• Cabling: 1771-PSCC Remote 5.5 ft

• Frequency: 47–63 Hz

• Dimensions: 4.5 × 12.4 × 6.3 in (115 × 317 × 160 mm)

• Backplane Current: 1.1A typical, 1.6A maximum at 5V DC

Key Features

The 1771-QB supports high-speed motion control, providing accurate position feedback for each axis. Its transducer interface directly connects to Temposonics II, Balluff, or Norstat linear displacement devices. Velocities reach up to 327.67 inches per second (3.2767 m/s).

With analog outputs, discrete I/O, and dual-axis control, this module ensures precise hydraulic and machine motion integration. The compact design and high update rate of 2 ms per axis enhance real-time PLC performance.

Industrial Applications

The Allen-Bradley 1771-QB is ideal for motion control, industrial automation, hydraulic integration, and high-speed positioning tasks in manufacturing environments. It is suitable for systems requiring precise displacement measurement and feedback.