Allen-Bradley 1731-CA 1700 Series Resolver Interface Module

The Allen-Bradley 1731-CA, also cataloged as the 1731-CA Resolver Interface Module, operates as a dedicated hardware component for converting angular resolver signals into digital position feedback within 1700 Series PLC racks.

Hardware Specifications

Industrial Control & Backplane Communication Properties

As a specialized feedback acquisition unit within Allen-Bradley control architectures, the 1731-CA delivers high-precision angular tracking and real-time bus interaction:

• Backplane Bus Communication Velocity: High-speed parallel backplane logic transfers 10-bit absolute position updates directly to central processor memory within fixed scan cycles, minimizing position reporting lag.
• Profinet / EtherNet/IP Deterministic Networks: Formats raw rotor position measurements for high-level motion logic, transmitting deterministic feedback values across upstream PLC network interfaces.
• I/O Density Scaling: Accommodates a dedicated 8-pin resolver terminal interface within a compact rack footprint, enabling single-channel motion feedback without adding external signal conversion electronics.

Frequently Asked Questions

Q: What is the maximum current draw of the 1731-CA module from the backplane power rail?

A: The 1731-CA module draws a maximum current of 675 mA from the rack supply during active resolver excitation and signal decoding.

Q: What physical connection interface is utilized for field excitation and signal wiring?

A: The module incorporates a dedicated 8-pin connector for terminating resolver excitation and sine/cosine feedback wiring.

Field Installation Guidelines

Adherence to standard electrical installation protocols is required to maintain signal integrity and prevent noise coupling:

• Connector Termination and Mechanical Seating: Insert the 8-pin wiring harness firmly into the front terminal block. Align the module card edges with the 1700 Series chassis guide rails and push until the rear backplane connector fully seats.
• Shielding and Grounding: Always use individually shielded, twisted-pair cabling for resolver excitation and feedback signals. Ground the cable shield at the chassis ground bus bar only; do not connect the shield at the resolver end to prevent ground loops.
• Noise Segregation: Route resolver signal cables in dedicated low-voltage instrument raceways. Maintain a minimum physical spacing of 200 mm from three-phase AC power cables, variable frequency drives, and heavy motor leads.