Product Overview
The Allen-Bradley 1771-HRA is a resolver excitation module designed for the PLC-5 series, specifically for use with the IMC 120 System. This module generates sine and cosine signals to excite the stator of the IMC 120 resolver feedback, providing precise position feedback to controller modules. It is essential for applications requiring accurate motion control and positioning.
Technical Specifications Breakdown
Key parameters for the 1771-HRA are listed below for quick reference:
| Feature | Specification |
|---|---|
| Module Type | Resolver Excitation Module |
| Backplane Current | 1.7 Amperes |
| Max Input Frequency | 250 Kilohertz Differential Input |
| Outputs | +/- 10 Volt DC Analog Command |
| Module Update Period | 2 ms/axis |
| Fuse Voltage | 120 Volts |
| Dimensions | 3.5 x 6.5 x 2.0 in (89 x 165 x 51 mm) |
| Wiring Arm | 1771-WA |
Industry Applications
This module is commonly used in manufacturing environments where precise motion control is critical, such as CNC machining, robotic assembly, and packaging lines. The resolver excitation signals enable accurate position feedback, reducing downtime and improving product quality. Compared to standard encoder-based systems, resolver feedback offers higher reliability in harsh environments with vibration or contamination.
Installation & Setup Guidance
Mount the 1771-HRA in a 1771 I/O chassis slot. Connect the 1771-PS7 power supply via the 1771-CAS cable to the 12-pin Latch and Lock connector. Use the 1771-CAPR 12ft cable to connect to the termination panel. Ensure the green LED indicates power status. The module draws 1.7 Amperes from the backplane. Set the wiring arm to 1771-WA for proper connections.
Maintenance & Reliability
Periodically inspect the module for dust accumulation and ensure the LED indicators function correctly. Verify that the 1771-PS7 power supply delivers stable voltages (5V, 15V, 24V DC). The module's output frequency is 2.5 KHz with a maximum signal delay of 2 seconds from power-up to output. Keep the chassis slots clean and free of debris.
Compatibility & Integration
The 1771-HRA is compatible with the IMC 120 System and requires a 1771-PS7 power supply. It uses the 1771-CAS cable for power and the 1771-CAPR cable for termination. The module occupies 2 slots per ES and works with the 1771-WA wiring arm. It provides sine/cosine signals with a sinusoid output amplitude of 6.72V (RMS) minimum and 7.42V (RMS) maximum.
Selection Guide & Purchasing Advice
When selecting the 1771-HRA, verify that your system uses the IMC 120 resolver feedback and that the power supply is a 1771-PS7. AutoDCSTech offers this module with fast shipping and expert support. Please verify current lifecycle status and availability with AutoDCSTech before ordering.
Troubleshooting & Common Issues
If the green LED does not illuminate, check the 1771-PS7 power supply and cable connections. If position feedback is erratic, verify the resolver wiring and the 1771-CAPR cable integrity. The module's output current limit is 0.81A (min) and 0.35A (max); ensure the load does not exceed 80 Ohms. For persistent issues, consult the IMC 120 system manual.
Availability & Condition at AutoDCSTech
| Part Number | 1771-HRA |
|---|---|
| Availability | In Stock |
| Condition | New |
| Warranty | One Year |
| Origin | US |
