A phase detecting device includes a power input unit that receives an AC voltage; a phase detector that detects zero-crossing points of the AC voltage, and outputs a phase detecting signal when the zero-crossing points of the AC voltage are detected; and a power switch that selectively cuts off a flow of AC into the power input unit in response to a mode control signal. In a preferred embodiment, the guide device generally includes a support member having first and second arms mated thereto. A stabilizer or off-center stabilizer may be provided to further deflect the outsert portion of the logging tool toward an earth formation to increase detector proximity to the formation. The heat produced by the fuel cell stack is dissipated to the marine environment for heat management of the fuel cell power system. The saw blade section has a circular saw blade for cutting the workpiece.