摘要 |
<p>The hypsometer comprises an open boiling vessel consisting of a vessel flask containing the measuring fluid and of a vessel neck attached to said vessel. An electrical heating resistor plunges into said measuring fluid. A temperature sensor measures the boiling temperature of said measuring fluid. The hypsometer comprises an adaptive control system for stabilizing the position of condensation zone in the vessel neck which adjusts the heating capacity to a command value corresponding to the specific boiling temperature involved. In the simplest case, such control is realized by using, as heating resistor, a thermistor having a negative temperature coefficient. In this way, the heating capacity is adjusted, over the whole pressure range, to the specific needs. Thus, on the average, less heating capacity is needed, resulting in a considerable reduction of the battery weight.</p> |