Abstract: A method of determining a differential power condition includes comparing a voltage across a resistor to a first threshold. The voltage across the resistor is proportional to a difference between a first current and a second current. The method also includes comparing a difference between the first current and the second current to a second threshold. A differential power condition is determined in response to the voltage across the resistor exceeding the first threshold, the difference exceeding the second threshold, or both.

Abstract: A method of determining a differential power condition includes comparing a voltage across a resistor to a first threshold. The voltage across the resistor is proportional to a difference between a first current and a second current. The method also includes comparing a difference between the first current and the second current to a second threshold. A differential power condition is determined in response to the voltage across the resistor exceeding the first threshold, the difference exceeding the second threshold, or both.

Abstract: An apparatus for maintaining a uniform grade of the surface being excavated or leveled by a waterborne dredge. The apparatus includes a shore mounted laser that projects a horizontal beam which is utilized to establish a reference plane, a dredge mounted photo receiver responsive to the beam from said shore mounted laser, a hydraulic system for repositioning the dredge cutter in response to changes of position of the dredge relative to the reference plane established by the laser beam. The hydraulic system includes a specifically designed pulley arrangement which raises and lowers the dredge ladder to maintain the cutter at a constant elevation.

Abstract: A dredge swinging system for automatically swinging a dredge in a leftward and rightward direction a predetermined degree in response to the equalization of electronic compass output signals representative of the position of a dredge and electronic memory output signals representative of the degree to which it is desired that the dredge be swung.