Product Description:

The BTA20.4-ND-PP-VB-BS is a modular machine control board produced by Bosch Rexroth Indramat within the BTA20 Machine Control Boards series. It slots into the CNC rack of milling, turning, or grinding equipment and supervises axis drives, operator pushbuttons, and interlock chains. By combining field I/O sequencing with backplane messaging, the board serves as an interface between peripheral safety devices and the numerical control kernel, supporting coordinated motion and protecting the installation during routine industrial automation cycles.

Its communication backbone is INTERBUS-S / BT-BUS, presented on one inbound and one outbound fiber channel so that station-to-station handshaking travels deterministically across the cell. Remote frames transfer at 500 kbaud, carrying a fixed Interbus data field of 48 bits and an additional process image of 3 words. A single RS232 diagnostic port and dual RS422 links offer local service access, while the ring interface includes 1 In, 1 Out Interbus connections. The front panel is sealed to IP65, which supports washdown use, and the card measures 407 x 169 x 119 mm inside the control cabinet.

Two independent E-stop circuits interrupt motion power in less than 10 ms, and operators can trim feed rates through the pair of override switches when fine control is required. The board accepts 8 external 24 V inputs for limit switches or probe contacts and drives an equal number of transistorized 24 V outputs, each sourcing up to 200 mA. Logic circuitry draws at most 50 mA from the 5 V backplane so the module can share a supply with other boards, and a 4-bit gray code channel provides coarse spindle position feedback to higher-level logic. The mounting footprint is 375 x 137 x 119 mm, which keeps cable bends short and leaves space for airflow around neighboring drives.