Product Description:

The 5AC901.I485-00 is an add-on communication board from B & R Automation that belongs to the 5AC CNC Addon Modules series. Installed beside the primary control electronics, the board provides a dedicated serial link so the CNC system can exchange part programs, status information, or parameter data with external devices such as HMIs, inverters, or diagnostic laptops. Its purpose in an automation cabinet is to offload basic point-to-point traffic from higher-level fieldbus networks while retaining full electrical isolation between the control core and connected peripherals.

Only a single port is present, and that port supports RS232/RS422/RS485 signaling so the user can match the electrical layer to the remote device. The hardware count is 1 interface, which simplifies addressing and cabling. Data lines and logic share no common reference with the controller thanks to the board being Galvanically Isolated; this prevents ground loops or noise injection when the machine frame carries high currents. The port runs reliably up to 115 kbit/s, which covers typical CNC upload, download, and service tasks. A receive and transmit 16-byte FIFO buffer is integrated to smooth bursts at maximum speed, minimizing CPU interrupts during continuous file transfers.

The physical outlet is a DSUB, 9-pin, male connector that mates with standard serial cables. Internal supply demand remains low, with total consumption limited to 1 W, so thermal loading inside a sealed cabinet is negligible. Line termination is selected by a Slide switch located on the front edge, allowing quick adaptation to long multidrop wiring; factory default termination is off to avoid accidental double termination. The design omits a modem interface, providing no modem support, which helps reduce unnecessary signal conditioning components and keeps the module focused on direct wired links.