What is the purpose of the A2B (anti two block) device?

The purpose of the A2B (anti two block) device is to ensure safe operation by stopping the crane before a two-block condition occurs. Two-blocking occurs when the hook travels too close to the hoist mechanism, potentially leading to serious equipment damage or accidents. By monitoring the distance between the hook and the boom tip, the A2B device automatically engages to stop the lifting motion, thereby preventing this dangerous situation.

While other options touch on aspects of crane operation, they do not relate directly to the specific function of the A2B device, which is primarily focused on maintaining safety standards during lifting operations.