Which device would typically not be involved in limiting the boom movement of a crane?

The hoist drum indicator is used to show the amount of wire rope that is wound and unwound from the hoist drum, providing crucial information to the operator regarding the load and height. However, it does not directly influence or restrict the movement of the crane's boom.

In contrast, devices such as the anti two-blocking device, boom angle indicator, and luffing jib limiting device are specifically designed to maintain safe operational parameters of the crane. The anti two-blocking device prevents the hook block from coming into contact with the boom, which could lead to damage or failure. The boom angle indicator provides real-time feedback on the angle of the boom, allowing operators to ensure they remain within safe operating limits. The luffing jib limiting device helps manage the extent to which the jib can move, preventing it from moving beyond designated angles. Thus, these devices are integral to controlling boom movement, whereas the hoist drum indicator serves a different, though still important, function in crane operations.