Product Description:

The 8AC121.60-1 Powerlink encoder module is built by B & R Automation as part of the 8AC Powerlink Modules series. It occupies a compact slice of a servo rack and serves as the dedicated interface that feeds position and speed data from an external encoder into a synchronized motion bus. By translating raw sin/cos signals and digital frames into deterministic Powerlink telegrams, the unit helps drives and controllers maintain precise axis coordination in packaging lines, pick-and-place gantries, and other multi-axis assemblies. Installation requires no additional power supply because the module draws its operating energy directly from the backplane.

Communication between the module and the host controller uses a serial layer running at 9600 baud, and data travels over the differential RS485 channel provided on the backplane. On the field side, one encoder connects through the HIPERFACE port, giving the module a single input channel without requiring auxiliary adapters. The module has no electrical isolation, yet integrated diagnostics continuously monitor supply, signal, and line status so faults are reported immediately. The analog sin/cos track is sampled at up to 200 kHz with differential, asymmetrical signaling, and quadrature interpolation produces a resolution of 16384 times the encoder line count. All conductors terminate in a 15-pin female DSUB, and two shield pins are tied together for noise suppression. With the encoder rail fully loaded, the electronics draw only 2.1 W, which helps limit heat inside the cabinet.

Up to 170 mA of regulated 5 V is supplied to the sensor, and the circuitry tolerates common-mode offsets of ±7 V between module ground and encoder housing. Feedback cables may extend to 50 m without compromising differential integrity when a line-end resistor of 120 Ω is installed near the sensor connector. The board must be installed in slots 2, 3, or 4 of the Powerlink rack so the internal address lines match the intended layout. Local processing of sin/cos amplitudes reduces jitter, allowing the controller to receive position words within the same cycle and maintain deterministic motion control across synchronized axes.