| 摘要 |
A detector for sensing the presence of polar fluids includes a pair of detection probes and a circuit for providing an oscillating voltage across the probes. A power supply for the detector includes a transformer with a split secondary, with at least one secondary having a floating ground. One of the probes is connected to the floating ground. The other probe is connected to the input of a fluid detection logic circuit. The input is applied to an inverter having an activation threshold of approximately six volts. The resulting activation threshold of the detector circuit is sufficiently low to be activated by the oscillating voltage so as to produce a polar fluid output signal when the probes are immersed in a polar fluid, but sufficiently high so as not to be affected by stray voltages induced in the probes by conventional power lines, such as 120 VAC lines, contacting the polar fluid. |
