Abstract: Methods and apparatus to facilitate ground fault detection with a single coil and an oscillator are disclosed. An example ground fault detection device includes a sense coil including a secondary winding surrounding a line conductor and a neutral conductor, the line conductor and the neutral conductor forming a primary winding. The example ground fault detection device also includes a voltage oscillator connected in series with the secondary winding to drive an oscillation component, and at least one of a detector or an amplifier connected in series with the secondary winding to detect at least one of a neutral-to-ground fault or a line-to-ground fault.

Abstract: An apparatus and method for recycling or maintaining the latent heat of vaporization in work producing cycles such as the Rankine cycle by eliminating phase changes by replacing the condenser in such cycles with a compressor and restricting or limiting the expansion to reduce compressor work requirements.The standard compound turbine prevalent today consisting of a single Curtis stage in tandem with pressure compounded stages has been replaced with several two-row Curtis stages.An alternative embodiment utilizes one or several two-row Curtis stages and a condenser as in the Rankine cycle but limits the expansion, maintaining a relatively high pressure typical in exhaust from this type of turbines. The high pressure maintains the temperature of the condensate sufficiently high to eliminate feed water preheating.Sacrifice of low pressure output is compensated in both cases by salvaging latent heat of vaporization which would not be possible economically, if expansion carried to the maximum.