Allen-Bradley 1771-QB PLC-5 Linear Positioning Module

Product Overview

The Allen-Bradley 1771-QB functions as a high-speed Linear Positioning Module designed for the 1771 Universal I/O chassis. This module provides precise closed-loop control of hydraulic or electric servo-actuators by interfacing directly with linear displacement transducers (LDTs). It processes position data from industry-standard sensors like MTS Temposonics and Balluff BTL series to execute accurate motion profiles. We supply this unit in 100% Brand New condition, offering a critical hardware solution for maintaining legacy PLC-5 systems that require high-resolution positioning without upgrading the entire control architecture.

Technical Specifications

• Module Type: Linear Positioning Module

• Compatible Transducers: MTS Temposonics, Balluff BTL, Norstat GYRG

• Sampling Period: 2 ms

• Analog Output Resolution: 12-bit

• Analog Output Ranges: +/-10V DC, +/-20 mA, +/-50 mA, +/-100 mA

• Discrete Inputs: 10-30V DC (Logic 1), 0-4V DC (Logic 0)

• Discrete Outputs: Single-ended, sourcing (100 mA max)

• Backplane Current: 1.6A max @ 5VDC

• Wiring Arm: 1771-WN (40 terminals)

• Slot Width: 1 Slot

• Fuse Protection: 3 Amperes, 250 Volts (Normal-Blow)

• Unit Weight: 6.00 lbs (2.72 kg)

Engineering Advantages

The 1771-QB delivers specialized motion control capabilities to the PLC-5 platform through several key engineering features:

• High-Speed Loop Execution: The module updates position data every 2 ms per axis. This rapid sampling ensures the controller responds instantly to dynamic changes in the actuator path, maintaining tight tolerances in precision wood processing, metal forming, and plastic injection molding applications.

• Versatile Servo Interfacing: Integrated analog outputs support multiple signal ranges, including high-current +/-100 mA drives. This versatility allows the 1771-QB to drive various servo valves directly, eliminating the need for external signal conditioners or intermediate amplifiers.

• Broad Transducer Compatibility: The hardware interfaces seamlessly with magnetostrictive transducers from major manufacturers. By supporting multiple LDT protocols, the module allows engineers to utilize existing field instrumentation during system repairs or machine overhauls.

• Simplified Field Wiring: The 1771-WN 40-terminal wiring arm facilitates clean and organized conductor management. The terminal design accommodates up to 14 AWG stranded wire, providing robust electrical connections that withstand the continuous vibration of heavy industrial environments.

FAQs

• Does the 1771-QB require a separate power supply for the transducers?

  Yes. While the module draws logic power from the 1771 backplane, you must provide external power to the linear displacement transducers and the discrete I/O circuits according to the sensor manufacturer's specifications.

• Is this a Brand New original product?

  Yes. We guarantee this 1771-QB is 100% Brand New original stock. For precision motion control, using new hardware ensures that the 12-bit analog-to-digital converters and timing circuits perform with the exact accuracy defined by the original factory calibration.

• Can I replace a failed 1771-QB without rewiring the system?

  Yes. If you currently use a 1771-WN wiring arm, you can swing the arm away, replace the module in the chassis, and reattach the arm. This "plug-and-play" capability minimizes downtime and prevents wiring errors during maintenance.

• Which PLC processors support this module?

  The 1771-QB operates in any 1771 Universal I/O chassis controlled by a PLC-5 processor. It occupies a single slot and communicates via the standard I/O transfer mechanism.