Product Summary
The Allen-Bradley 1771-HRA Resolver Excitation Module delivers critical sine and cosine signals for the IMC 120 system. This module excites the resolver stator to provide accurate position feedback to your controller. It operates with a 1771-PS7 power supply for reliable performance.
Expert Technical Evaluation & Performance Review
Signal Generation Accuracy
The 1771-HRA generates a sinusoid output with a minimum amplitude of 6.72V RMS. This module achieves a maximum amplitude of 7.42V RMS for consistent resolver excitation. Its sine-cosine matching amplitude stays below 0.3% for precise positioning. The module maintains a strict 90-degree sine-to-cosine relationship within 4.5 minutes. This accuracy ensures your system receives reliable positional data every cycle.
Output Frequency and Distortion Control
This module operates at a fixed output frequency of 2.5 KHz for stable resolver communication. It keeps total harmonic distortion (THD) at a maximum of 0.1% for clean signals. The maximum offset voltage is only 0.01V DC to prevent baseline errors. A sine phase offset of 0.45 degrees and sine drift of +/-5.4 minutes guarantee repeatable performance. These specifications make the 1771-HRA ideal for high-precision motion control applications.
Power and Load Management
The 1771-HRA draws backplane current of 1.7 amperes from the chassis. Its maximum wattage rating is 9.06 Watts for efficient energy use. The module supports an output current limit ranging from 0.35A minimum to 0.81A maximum. It handles a maximum output inductive load of 80 Ohms at 80 degrees. A maximum signal delay time of 2 seconds from power-up ensures rapid system readiness.
Installation and Wiring Requirements
Install this module into any standard 1771 I/O chassis slot. Use the 1771-WA wiring arm for secure field connections. Connect the 1771-PS7 power supply using a 1771-CAS cable to the 12-pin connector. A green LED indicator confirms power status after installation. The module uses a 1771-CAPR 12ft cable to link to the termination panel. Its dimensions are 3.5 x 6.5 x 2.0 inches for easy mounting.
System Compatibility and Feedback
This module works exclusively with the IMC 120 system for resolver feedback. It provides sine and cosine signals to excite the resolver stator. The controller modules then receive accurate position data for closed-loop control. An update period of 2 ms per axis supports fast response times. The pulse capture time ranges from 50 to 9.999 microseconds for flexible tuning.
Procurement Considerations for Engineers
Verify your system requires the 1771-HRA for resolver excitation tasks. Check that your power supply is a 1771-PS7 model for proper voltage delivery. Ensure your chassis has an available slot for this single-slot module. Confirm the input frequency of 250 KHz differential input matches your controller. Always use the specified 1771-CAPR cable for reliable signal transmission.
Logistics & Standard Packaging Details
- One Allen-Bradley 1771-HRA Resolver Excitation Module
- Product is individually packaged in anti-static protective material
- Original Allen-Bradley part number and label are clearly visible
- Express delivery shipping is available via FedEx, UPS, and DHL
- Module is sourced from trusted industrial automation supply chains
