ABB BC25-40-31 DC Contactor With Auxiliary Block

ABB's BC25-40-31 is a DC-operated contactor from the BC25 family designed to switch moderate power loads under control of a low-voltage signal. It uses a 24 VDC coil, which aligns with common PLC and relay logic outputs in machine automation, and it ships with an integrated auxiliary contact block to add signaling and interlock capabilities without extra assemblies. The auxiliary block is part of the BC25-40-31 configuration, enabling additional control contacts to monitor the operated load, feed back status to a control system, or implement sequencing logic in motor-start or process-control circuits. This arrangement minimizes wiring complexity in control panels by combining the main switching function with auxiliary signaling in a single compact unit. Typical applications include starting and stopping motors on conveyors, fans, pumps, and other industrial equipment where reliable DC-coil control and extra contact points for interlocks or feedback are beneficial.