Product Description:

The 8BAC0122.000-1 is a resolver and encoder I/O module manufactured by B & R Automation for the 8BA ACOPOS Modules series. Installed alongside an ACOPOS inverter, the unit converts analog resolver feedback into digital position data so the drive can regulate torque and speed within an automated axis. By monitoring rotational position through differential signal pairs, it supplies the controller with precise angle information without requiring a separate feedback interface. Its compact form factor allows placement inside the ACOPOS rack, sharing the common backplane power and communication bus.

Its measurement chain starts with a 14-bit successive-approximation ADC that digitizes the resolver sine and cosine voltages. A permissible common-mode input of ±20 V max protects the amplifiers when long cables pick up ground offsets. The internal excitation frequency is fixed at 10 kHz, synchronized with standard resolver carriers, and an input filter is tuned to that frequency. Electrical loading on the sensor lines is limited by an impedance of 10.4 kΩ - j 11.1 kΩ, so cable capacitance has minimal effect on phase accuracy. For distributed axes, the module can sit up to 100 m from the encoder without degrading signal fidelity. With a resolver ratio of 0.5 ± 10%, it interpolates each pole pair into 22 600 digital counts to yield fine position resolution.

The excitation driver supplies a sinusoidal carrier of 3 Veff and can deliver up to 50 mAeff, providing sufficient magnetization for low-impedance resolver windings while remaining within the module’s 1 W power ceiling. All feedback lines exit through the front-mounted 9-pin male DSUB connector, and differential signal transmission further improves noise immunity across the machine harness. Continuous encoder monitoring is active, raising alerts when amplitude or phase drift occurs. Rated for ambient temperatures up to 55 °C, the board tolerates installation in sealed cabinets on high-density drive panels.