Abstract: Crane apparatus having a pendant control with two stage operational switches is provided for use with a control system for maximum precision and efficiency during operation. The two stage switches allow for fast or slow crane movement as required. Boom construction is also presented for easy manufacture and superior strength under load.

Abstract: The present invention relates to a wire supply sensing apparatus (4) for monitoring the supply of wire (3) to a wire receiver (5) from a wire supply source (1). The sensing apparatus (4) is comprised of a tangled wire sensor (7) and a wire supply continuity sensor (9). The wire supply continuity sensor (9) has a sensing arm (23) which responds to the absence of wire due to wire breakage or depletion of the wire supply from the source (1). Upon wire breakage or depletion the sensing arm (23) controls an electric switch (27) which signals a controller (33) to turn off electric power at the wire receiving apparatus (5). The tangled wire sensor (9) has a plunger (13) including a tension sensing channel (15) for detecting a tangle (37) in the wire. Tension caused by the tangle (37) provides a force against the plunger (13) to move the plunger (13) to a position indicating the presence of a sensed tangle.