A power generator is associated with a crane boom at or near the tip of the boom. The generator responds to movement of the lifting cable to initiate the transmission of a signal to a crane controller. The signal serves as a start-up or a wake-up signal to the crane controller which may then immediately analyze operation of, for example, an anti-two block device associated with the boom tip. The crane controller may then control the operation of the crane in accordance with signals received from the anti-two block device or immediately identify malfunctions of the anti-two block device and control the crane operations accordingly.